path: root/docs/gnurl.1

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.Dd May 22, 2019
.Dt GNURL 1
.Os
.Sh NAME
.Nm gnurl
.Nd transfer a URL
.Sh SYNOPSIS
.Nm
[options / URLs]
.Sh DESCRIPTION
.Nm
is a tool to transfer data from or to a server, using one of the supported
protocols (DICT, FILE, FTP, FTPS, GOPHER, HTTP, HTTPS, IMAP, IMAPS, LDAP,
LDAPS, POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET
and TFTP). The command is designed to work without user interaction.
.Pp
gnurl offers a busload of useful tricks like proxy support, user
authentication, FTP upload, HTTP post, SSL connections, cookies, file
transfer resume, Metalink, and more. As you will see below, the number
of features will make your head spin!
.Pp
gnurl is powered by libgnurl for all transfer-related features. See
.Xr libcurl 3
for details.
.Ss URL
The URL syntax is protocol-dependent. You'll find a detailed
description in RFC 3986.
.Pp
You can specify multiple URLs or parts of URLs by writing part sets
within braces as in:
.Pp
.Dl http://site.{one,two,three}.com
.Pp
or you can get sequences of alphanumeric series by using [] as in:
.Pp
.Dl  ftp://ftp.example.com/file[1-100].txt
.Pp
.Dl  ftp://ftp.example.com/file[001-100].txt    (with leading zeros)
.Pp
.Dl  ftp://ftp.example.com/file[a-z].txt
.Pp
Nested sequences are not supported, but you can use several ones next
to each other:
.Pp
.Dl  http://example.com/archive[1996-1999]/vol[1-4]/part{a,b,c}.html
.Pp
You can specify any amount of URLs on the command line. They will be
fetched in a sequential manner in the specified order. You can specify
command line options and URLs mixed and in any order on the command
line.
.Pp
You can specify a step counter for the ranges to get every Nth number
or letter:
.Pp
.Dl  http://example.com/file[1-100:10].txt
.Pp
.Dl  http://example.com/file[a-z:2].txt
.Pp
When using [] or {} sequences when invoked from a command line prompt,
you probably have to put the full URL within double quotes to avoid
the shell from interfering with it. This also goes for other
characters treated special, like for example '&', '?' and '*'.
.Pp
Provide the IPv6 zone index in the URL with an escaped percentage sign
and the interface name. Like in
.Pp
.Dl  http://[fe80::3%25eth0]/
.Pp
If you specify URL without protocol:// prefix, curl will attempt to
guess what protocol you might want. It will then default to HTTP but
try other protocols based on often-used host name prefixes. For
example, for host names starting with "ftp." curl will assume you want
to speak FTP.
.Pp
curl will do its best to use what you pass to it as a URL. It is not
trying to validate it as a syntactically correct URL by any means but
is instead \fBvery\fP liberal with what it accepts.
.Pp
curl will attempt to re-use connections for multiple file transfers,
so that getting many files from the same server will not do multiple
connects / handshakes. This improves speed. Of course this is only
done on files specified on a single command line and cannot be used
between separate curl invokes.
.Ss PROGRESS METER
gnurl normally displays a progress meter during operations, indicating
the amount of transferred data, transfer speeds and estimated time
left, etc. The progress meter displays number of bytes and the speeds
are in bytes per second. The suffixes (k, M, G, T, P) are 1024
based. For example 1k is 1024 bytes. 1M is 1048576 bytes.
.Pp
curl displays this data to the terminal by default, so if you invoke
curl to do an operation and it is about to write data to the terminal,
it \fIdisables\fP the progress meter as otherwise it would mess up the
output mixing progress meter and response data.
.Pp
If you want a progress meter for HTTP POST or PUT requests, you need
to redirect the response output to a file, using shell redirect (>),
.Fl o | -output
or similar.
.Pp
It is not the same case for FTP upload as that operation does not spit
out any response data to the terminal.
.Pp
If you prefer a progress "bar" instead of the regular meter,
.Fl # | -progress-bar
is your friend.
You can also disable the progress meter completely with the
.Fl s | -silent
option.
.Ss OPTIONS
Options start with one or two dashes. Many of the options require an
additional value next to them.
.Pp
The short "single-dash" form of the options,
.Fl d
for example, may be used with or without a space between it and its value,
although a space is a recommended separator.
The long "double-dash" form,
.Fl d | -data
for example, requires a space between it and its value.
.Pp
Short version options that don't need any additional values can be used
immediately next to each other, like for example you can specify all the
options
.Fl O ,
.Fl L
and
.Fl v
at once as
.Fl OLv .
.Pp
In general, all boolean options are enabled with
.Fl -option
and yet again disabled with
.Fl -no-option .
That is, you use the exact same option name but prefix it with "no-".
However, in this list we mostly only list and show the
.Fl -option
version of them. (This concept with
.Fl -no
options was added in 7.19.0. Previously most options were toggled
on/off on repeated use of the same command line option.)
.Bl -tag -width indent
.It Fl -abstract-unix-socket Ar <path>
(HTTP) Connect through an abstract Unix domain socket, instead of using the network.
Note: netstat shows the path of an abstract socket prefixed with '@', however
the <path> argument should not have this leading character.
.Pp
Added in 7.53.0.
.It Fl -alt-svc Ar <file name>
(HTTPS) WARNING: this option is experimental. Do not use in production.
.Pp
This option enables the alt-svc parser in curl. If the file name points to an
existing alt-svc cache file, that will be used. After a completed transfer,
the cache will be saved to the file name again if it has been modified.
.Pp
Specify a "" file name (zero length) to avoid loading/saving and make curl
just handle the cache in memory.
.Pp
If this option is used several times, curl will load contents from all the
files but the the last one will be used for saving.
.Pp
Added in 7.64.1.
.It Fl -anyauth
(HTTP) Tells curl to figure out authentication method by itself, and use the most
secure one the remote site claims to support. This is done by first doing a
request and checking the response-headers, thus possibly inducing an extra
network round-trip. This is used instead of setting a specific authentication
method, which you can do with
.Fl -basic ,
.Fl -digest ,
.Fl -ntlm ,
and
.Fl -negotiate .
.Pp
Using
.Fl -anyauth
is not recommended if you do uploads from stdin, since it may
require data to be sent twice and then the client must be able to rewind. If
the need should arise when uploading from stdin, the upload operation will
fail.
.Pp
Used together with
.Fl u | -user .
.Pp
See also
.Fl -proxy-anyauth ,
.Fl -basic
and
.Fl -digest .
.It Fl a | -append
(FTP SFTP) When used in an upload, this makes curl append to the target file
instead of overwriting it.
If the remote file doesn't exist, it will be created.
Note that this flag is ignored by some SFTP servers (including OpenSSH).
.It Fl -basic
(HTTP) Tells curl to use HTTP Basic authentication with the remote host. This is the
default and this option is usually pointless, unless you use it to override a
previously set option that sets a different authentication method (such as
.Fl -ntlm ,
.Fl -digest ,
or
.Fl -negotiate Ns ).
.Pp
Used together with
.Fl u | -user .
.Pp
See also
.Fl -proxy-basic .
.It Fl -cacert Ar <file>
(TLS) Tells curl to use the specified certificate file to verify the
peer. The file may contain multiple CA certificates. The
certificate(s) must be in PEM format. Normally curl is built to use a
default file for this, so this option is typically used to alter that
default file.
.Pp
curl recognizes the environment variable named 'CURL_CA_BUNDLE' if it is
set, and uses the given path as a path to a CA cert bundle. This option
overrides that variable.
.Pp
The windows version of curl will automatically look for a CA certs file named
.Pa curl-ca-bundle.crt ,
either in the same directory as curl.exe, or in the
Current Working Directory, or in any folder along your PATH.
.Pp
If curl is built against the NSS SSL library, the NSS PEM PKCS#11 module
(libnsspem.so) needs to be available for this option to work properly.
.Pp
(iOS and macOS only) If curl is built against Secure Transport, then this
option is supported for backward compatibility with other SSL engines, but it
should not be set. If the option is not set, then curl will use the
certificates in the system and user Keychain to verify the peer, which is the
preferred method of verifying the peer's certificate chain.
.Pp
(Schannel only) This option is supported for Schannel in Windows 7 or later with
libcurl 7.60 or later. This option is supported for backward compatibility
with other SSL engines; instead it is recommended to use Windows' store of
root certificates (the default for Schannel).
.Pp
If this option is used several times, the last one will be used.
.It Fl -capath Ar <dir>
(TLS) Tells curl to use the specified certificate directory to verify the
peer. Multiple paths can be provided by separating them with ":" (e.g.
\&"path1:path2:path3"). The certificates must be in PEM format, and if curl is
built against OpenSSL, the directory must have been processed using the
c_rehash utility supplied with OpenSSL. Using
.Fl -capath
can allow OpenSSL-powered curl to make SSL-connections much more
efficiently than using
.Fl -cacert
if the
.Fl -cacert
file contains many CA certificates.
.Pp
If this option is set, the default capath value will be ignored, and if it is
used several times, the last one will be used.
.It Fl -cert-status
(TLS) Tells curl to verify the status of the server certificate by using the
Certificate Status Request (aka. OCSP stapling) TLS extension.
.Pp
If this option is enabled and the server sends an invalid (e.g. expired)
response, if the response suggests that the server certificate has been revoked,
or no response at all is received, the verification fails.
.Pp
This is currently only implemented in the OpenSSL, GnuTLS and NSS backends.
.Pp
Added in 7.41.0.
.It Fl -cert-type Ar <type>
(TLS) Tells curl what type the provided client certificate is
using. PEM, DER, ENG and P12 are recognized types.  If not specified,
PEM is assumed.
.Pp
If this option is used several times, the last one will be used.
.Pp
See also
.Fl E | -cert
and
.Fl -key
and
.Fl -key-type .
.It Fl E Ar <certificate[:password]> | Fl -cert Ar <certificate[:password]>
(TLS) Tells curl to use the specified client certificate file when getting a file
with HTTPS, FTPS or another SSL-based protocol. The certificate must be in
PKCS#12 format if using Secure Transport, or PEM format if using any other
engine.  If the optional password isn't specified, it will be queried for on
the terminal. Note that this option assumes a \&"certificate" file that is the
private key and the client certificate concatenated! See \fI-E, --cert\fP and \fI--key\fP to
specify them independently.
.Pp
If curl is built against the NSS SSL library then this option can tell
curl the nickname of the certificate to use within the NSS database defined
by the environment variable SSL_DIR (or by default /etc/pki/nssdb). If the
NSS PEM PKCS#11 module (libnsspem.so) is available then PEM files may be
loaded. If you want to use a file from the current directory, please precede
it with "./" prefix, in order to avoid confusion with a nickname.  If the
nickname contains ":", it needs to be preceded by "\\" so that it is not
recognized as password delimiter.  If the nickname contains "\\", it needs to
be escaped as "\\\\" so that it is not recognized as an escape character.
.Pp
If curl is built against OpenSSL library, and the engine pkcs11 is available,
then a PKCS#11 URI (RFC 7512) can be used to specify a certificate located in
a PKCS#11 device. A string beginning with "pkcs11:" will be interpreted as a
PKCS#11 URI. If a PKCS#11 URI is provided, then the \fI--engine\fP option will be set
as "pkcs11" if none was provided and the \fI--cert-type\fP option will be set as
"ENG" if none was provided.
.Pp
(iOS and macOS only) If curl is built against Secure Transport, then the
certificate string can either be the name of a certificate/private key in the
system or user keychain, or the path to a PKCS#12-encoded certificate and
private key. If you want to use a file from the current directory, please
precede it with "./" prefix, in order to avoid confusion with a nickname.
.Pp
(Schannel only) Client certificates must be specified by a path
expression to a certificate store. (Loading PFX is not supported; you can
import it to a store first). You can use
"<store location>\\<store name>\\<thumbprint>" to refer to a certificate
in the system certificates store, for example,
"CurrentUser\\MY\\934a7ac6f8a5d579285a74fa61e19f23ddfe8d7a". Thumbprint is
usually a SHA-1 hex string which you can see in certificate details. Following
store locations are supported: CurrentUser, LocalMachine, CurrentService,
Services, CurrentUserGroupPolicy, LocalMachineGroupPolicy,
LocalMachineEnterprise.
.Pp
If this option is used several times, the last one will be used.
.Pp
See also \fI--cert-type\fP and \fI--key\fP and \fI--key-type\fP.
.It Fl -ciphers Ar <list of ciphers>
(TLS) Specifies which ciphers to use in the connection. The list of ciphers must
specify valid ciphers. Read up on SSL cipher list details on this URL:
.Pp
.Dl https://curl.haxx.se/docs/ssl-ciphers.html
.Pp
If this option is used several times, the last one will be used.
.It Fl -compressed-ssh
(SCP SFTP) Enables built-in SSH compression.
This is a request, not an order; the server may or may not do it.
.Pp
Added in 7.56.0.
.It Fl -compressed
(HTTP) Request a compressed response using one of the algorithms curl supports, and
save the uncompressed document.  If this option is used and the server sends
an unsupported encoding, curl will report an error.
.It Fl K Ar <file> | -config <file>
Specify a text file to read curl arguments from. The command line
arguments found in the text file will be used as if they were provided
on the command line.
.Pp
Options and their parameters must be specified on the same line in the
file, separated by whitespace, colon, or the equals sign. Long option
names can optionally be given in the config file without the initial
double dashes and if so, the colon or equals characters can be used as
separators. If the option is specified with one or two dashes, there
can be no colon or equals character between the option and its
parameter.
.Pp
If the parameter contains whitespace (or starts with : or =), the parameter
must be enclosed within quotes. Within double quotes, the following escape
sequences are available: \\\\, \\", \\t, \\n, \\r and \\v. A backslash
preceding any other letter is ignored. If the first column of a config line is
a '#' character, the rest of the line will be treated as a comment. Only write
one option per physical line in the config file.
.Pp
Specify the filename to
.Fl K |-config
as '-' to make curl read the file from stdin.
.Pp
Note that to be able to specify a URL in the config file, you need to specify
it using the
.Fl -url
option, and not by simply writing the URL on its own line.
So, it could look similar to this:
.Pp
.Dl url = "https://curl.haxx.se/docs/"
.Pp
When curl is invoked, it (unless
.Fl q | -disable
is used) checks for a default config file and uses it if found.
The default config file is checked for in the following places in this order:
.Pp
1) curl tries to find the "home dir": It first checks for the CURL_HOME and
then the HOME environment variables. Failing that, it uses getpwuid() on
Unix-like systems (which returns the home dir given the current user in your
system). On Windows, it then checks for the APPDATA variable, or as a last
resort the '%USERPROFILE%\\Application Data'.
.Pp
2) On windows, if there is no _curlrc file in the home dir, it checks for one
in the same dir the curl executable is placed. On Unix-like systems, it will
simply try to load .curlrc from the determined home dir.
.Bl -literal -offset indent -compact
# --- Example file ---
# this is a comment
url = "example.com"
output = "curlhere.html"
user-agent = "superagent/1.0"

# and fetch another URL too
url = "example.com/docs/manpage.html"
-O
referer = "http://nowhereatall.example.com/"
# --- End of example file ---
.El
This option can be used multiple times to load multiple config files.
.It Fl -connect-timeout Ar <seconds>
Maximum time in seconds that you allow curl's connection to take.
This only limits the connection phase, so if curl connects within the
given period it will continue - if not it will exit.  Since version
7.32.0, this option accepts decimal values.
.Pp
If this option is used several times, the last one will be used.
.Pp
See also
.Fl m | -max-time .
.It Fl -connect-to Ar <HOST1:PORT1:HOST2:PORT2>
For a request to the given HOST1:PORT1 pair, connect to HOST2:PORT2
instead.  This option is suitable to direct requests at a specific
server, e.g. at a specific cluster node in a cluster of servers. This
option is only used to establish the network connection. It does NOT
affect the hostname/port that is used for TLS/SSL (e.g. SNI,
certificate verification) or for the application protocols. "HOST1"
and "PORT1" may be the empty string, meaning "any host/port". "HOST2"
and "PORT2" may also be the empty string, meaning "use the request's
original host/port".
.Pp
A "host" specified to this option is compared as a string, so it needs
to match the name used in request URL. It can be either numerical such
as "127.0.0.1" or the full host name such as "example.org".
.Pp
This option can be used many times to add many connect rules.
.Pp
See also
.Fl -resolve
and
.Fl H | -header .
Added in 7.49.0.
.It Fl C Ar <offset> | Fl -continue-at Ar <offset>
Continue/Resume a previous file transfer at the given offset. The
given offset is the exact number of bytes that will be skipped,
counting from the beginning of the source file before it is
transferred to the destination.  If used with uploads, the FTP server
command SIZE will not be used by curl.
.Pp
Use "-C -" to tell curl to automatically find out where/how to resume the
transfer. It then uses the given output/input files to figure that out.
.Pp
If this option is used several times, the last one will be used.
.Pp
See also
.Fl r | -range .
.It Fl c Ar <filename> | Fl -cookie-jar Ar <filename>
(HTTP) Specify to which file you want curl to write all cookies after
a completed operation. Curl writes all cookies from its in-memory
cookie storage to the given file at the end of operations. If no
cookies are known, no data will be written. The file will be written
using the Netscape cookie file format. If you set the file name to a
single dash, "-", the cookies will be written to stdout.
.Pp
This command line option will activate the cookie engine that makes
curl record and use cookies. Another way to activate it is to use the
.Fl b | -cookie
option.
.Pp
If the cookie jar can't be created or written to, the whole curl
operation won't fail or even report an error clearly. Using
.Fl v | -verbose
will get a warning displayed, but that is the only
visible feedback you get about this possibly lethal situation.
.Pp
If this option is used several times, the last specified file name
will be used.
.It Fl b Ar <data|filename> | Fl -cookie Ar <data|filename>
(HTTP) Pass the data to the HTTP server in the Cookie header. It is
supposedly the data previously received from the server in a
"Set-Cookie:" line.  The data should be in the format "NAME1=VALUE1;
NAME2=VALUE2".
.Pp
If no '=' symbol is used in the argument, it is instead treated as a
filename to read previously stored cookie from. This option also
activates the cookie engine which will make curl record incoming
cookies, which may be handy if you're using this in combination with
the
.Fl L | -location
option or do multiple URL transfers on the
same invoke. If the file name is exactly a minus ("-"), curl will
instead the contents from stdin.
.Pp
The file format of the file to read cookies from should be plain HTTP
headers (Set-Cookie style) or the Netscape/Mozilla cookie file format.
.Pp
The file specified with
.Fl b | -cookie
is only used as input. No cookies will be written to the file. To
store cookies, use the
.Fl c | -cookie-jar
option.
.Pp
Exercise caution if you are using this option and multiple transfers
may occur.  If you use the NAME1=VALUE1; format, or in a file use the
Set-Cookie format and don't specify a domain, then the cookie is sent
for any domain (even after redirects are followed) and cannot be
modified by a server-set cookie. If the cookie engine is enabled and a
server sets a cookie of the same name then both will be sent on a
future transfer to that server, likely not what you intended.  To
address these issues set a domain in Set-Cookie (doing that will
include sub domains) or use the Netscape format.
.Pp
If this option is used several times, the last one will be used.
.Pp
Users very often want to both read cookies from a file and write updated
cookies back to a file, so using both
.Fl b | -cookie
and
.Fl c | -cookie-jar
in the same command line is common.
.It Fl -create-dirs
When used in conjunction with the
.Fl o | -output
option, curl will create the necessary local directory hierarchy as
needed. This option creates the dirs mentioned with the
.Fl o | -output
option, nothing else. If the
.Fl -output
file name uses no dir or if the dirs it mentions already exist, no dir
will be created.
.Pp
To create remote directories when using FTP or SFTP, try
.Fl -ftp-create-dirs .
.It Fl -crlf
(FTP SMTP) Convert LF to CRLF in upload. Useful for MVS (OS/390).
.Pp
(SMTP added in 7.40.0)
.It Fl -crlfile Ar <file>
(TLS) Provide a file using PEM format with a Certificate Revocation
List that may specify peer certificates that are to be considered
revoked.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.19.7.
.It Fl -data-ascii Ar <data>
(HTTP) This is just an alias for
.Fl d | -data .
.It Fl -data-binary Ar <data>
(HTTP) This posts data exactly as specified with no extra processing
whatsoever.
.Pp
If you start the data with the letter @, the rest should be a
filename.  Data is posted in a similar manner as
.Fl d | -data
does, except that newlines and carriage returns are preserved and
conversions are never done.
.Pp
Like
.Fl d | -data
the default content-type sent to the server is
application/x-www-form-urlencoded. If you want the data to be treated
as arbitrary binary data by the server then set the content-type to
octet-stream:
.Pp
.Dl -H "Content-Type: application/octet-stream".
.Pp
If this option is used several times, the ones following the first
will append data as described in
.Fl d | -data .
.It Fl -data-raw Ar <data>
(HTTP) This posts data similarly to
.Fl d | -data
but without the special interpretation of the @ character.
.Pp
See also \fI-d, --data\fP. Added in 7.43.0.
.It Fl -data-urlencode Ar <data>
(HTTP) This posts data, similar to the other \fI-d, --data\fP options
with the exception that this performs URL-encoding.
.Pp
To be CGI-compliant, the <data> part should begin with a \fIname\fP
followed by a separator and a content specification. The <data> part
can be passed to curl using one of the following syntaxes:
.Bl -tag -width indent
.It content
This will make curl URL-encode the content and pass that on. Just be
careful so that the content doesn't contain any = or @ symbols, as
that will then make the syntax match one of the other cases below!
.It =content
This will make curl URL-encode the content and pass that on. The
preceding = symbol is not included in the data.
.It name=content
This will make curl URL-encode the content part and pass that on. Note
that the name part is expected to be URL-encoded already.
.It @filename
This will make curl load data from the given file (including any
newlines), URL-encode that data and pass it on in the POST.
.It name@filename
This will make curl load data from the given file (including any
newlines), URL-encode that data and pass it on in the POST. The name
part gets an equal sign appended, resulting in
\fIname=urlencoded-file-content\fP. Note that the name is expected to
be URL-encoded already.
.El
See also \fI-d, --data\fP and \fI--data-raw\fP. Added in 7.18.0.
.It Fl d Ar data | Fl -data Ar data
(HTTP) Sends the specified data in a POST request to the HTTP server,
in the same way that a browser does when a user has filled in an HTML
form and presses the submit button. This will cause curl to pass the
data to the server using the content-type
application/x-www-form-urlencoded.  Compare to \fI-F, --form\fP.
.Pp
\fI--data-raw\fP is almost the same but does not have a special
interpretation of the @ character. To post data purely binary, you
should instead use the \fI--data-binary\fP option.  To URL-encode the
value of a form field you may use \fI--data-urlencode\fP.
.Pp
If any of these options is used more than once on the same command
line, the data pieces specified will be merged together with a
separating &-symbol. Thus, using '-d name=daniel -d skill=lousy' would
generate a post chunk that looks like \&'name=daniel&skill=lousy'.
.Pp
If you start the data with the letter @, the rest should be a file
name to read the data from, or - if you want curl to read the data
from stdin. Multiple files can also be specified. Posting data from a
file named
'foobar' would thus be done with \fI-d, --data\fP @foobar. When --data is told to read
from a file like that, carriage returns and newlines will be stripped
out. If you don't want the @ character to have a special
interpretation use \fI--data-raw\fP instead.
.Pp
See also \fI--data-binary\fP and \fI--data-urlencode\fP and
\fI--data-raw\fP. This option overrides \fI-F, --form\fP and \fI-I,
--head\fP and \fI-T, --upload-file\fP.
.It Fl -delegation Ar LEVEL
(GSS/kerberos) Set LEVEL to tell the server what it is allowed to
delegate when it comes to user credentials.
.Bl -tag -width indent
.It none
Don't allow any delegation.
.It policy
Delegates if and only if the OK-AS-DELEGATE flag is set in the
Kerberos service ticket, which is a matter of realm policy.
.It always
Unconditionally allow the server to delegate.
.El
.It Fl -digest
(HTTP) Enables HTTP Digest authentication. This is an authentication
scheme that prevents the password from being sent over the wire in
clear text. Use this in combination with the normal \fI-u, --user\fP
option to set user name and password.
.Pp
If this option is used several times, only the first one is used.
.Pp
See also \fI-u, --user\fP and \fI--proxy-digest\fP and
\fI--anyauth\fP. This option overrides \fI--basic\fP and \fI--ntlm\fP
and \fI--negotiate\fP.
.It Fl -disable-eprt
(FTP) Tell curl to disable the use of the EPRT and LPRT commands when
doing active FTP transfers. Curl will normally always first attempt to
use EPRT, then LPRT before using PORT, but with this option, it will
use PORT right away. EPRT and LPRT are extensions to the original FTP
protocol, and may not work on all servers, but they enable more
functionality in a better way than the traditional PORT command.
.Pp
.Fl -eprt
can be used to explicitly enable EPRT again and
.Fl -no-eprt
is an alias for
.Fl -disable-eprt .
.Pp
If the server is accessed using IPv6, this option will have no effect
as EPRT is necessary then.
.Pp
Disabling EPRT only changes the active behavior. If you want to switch
to passive mode you need to not use \fI-P, --ftp-port\fP or force it
with \fI--ftp-pasv\fP.
.It Fl -disable-epsv
(FTP) (FTP) Tell curl to disable the use of the EPSV command when
doing passive FTP transfers. Curl will normally always first attempt
to use EPSV before PASV, but with this option, it will not try using
EPSV.
.Pp
--epsv can be used to explicitly enable EPSV again and --no-epsv is an
alias for \fI--disable-epsv\fP.
.Pp
If the server is an IPv6 host, this option will have no effect as EPSV
is necessary then.
.Pp
Disabling EPSV only changes the passive behavior. If you want to
switch to active mode you need to use \fI-P, --ftp-port\fP.
.It Fl q | -disable
If used as the first parameter on the command line, the \fIcurlrc\fP
config file will not be read and used. See the \fI-K, --config\fP for
details on the default config file search path.
.It Fl -disallow-username-in-url
(HTTP) This tells curl to exit if passed a url containing a username.
.Pp
See also
.Fl -proto .
Added in 7.61.0.
.It Fl -dns-interface Ar <interface>
(DNS) Tell curl to send outgoing DNS requests through
.Ar <interface> .
This option is a counterpart to
.Fl -interface
(which does not affect DNS). The supplied string must be an interface
name (not an address).
.Pp
See also
.Fl -dns-ipv4-addr
and
.Fl -dns-ipv6-addr .
.Fl -dns-interface
requires that the underlying libgnurl was built to support c-ares.
Added in 7.33.0.
.It Fl -dns-ipv4-addr Ar <address>
(DNS) Tell curl to bind to
.Ar <ip-address>
when making IPv4 DNS requests, so that the DNS requests originate from
this address. The argument should be a single IPv4 address.
.Pp
See also
.Fl -dns-interface
and
.Fl -dns-ipv6-addr .
.Fl -dns-ipv4-addr
requires that the underlying libgnurl was built to support c-ares.
Added in 7.33.0.
.It Fl -dns-ipv6-addr Ar <address>
(DNS) Tell curl to bind to
.Ar <ip-address>
when making IPv6 DNS requests, so that the DNS requests originate from
this address. The argument should be a single IPv6 address.
.Pp
See also \fI--dns-interface\fP and
\fI--dns-ipv4-addr\fP. \fI--dns-ipv6-addr\fP requires that the
underlying libgnurl was built to support c-ares. Added in 7.33.0.
.It Fl -dns-servers Ar <addresses>
Set the list of DNS servers to be used instead of the system default.
The list of IP addresses should be separated with commas. Port numbers
may also optionally be given as \fI:<port-number>\fP after each IP
address.

\fI--dns-servers\fP requires that the underlying libgnurl was built to support c-ares. Added in 7.33.0.
.It Fl -doh-url <URL>
(all) Specifies which DNS-over-HTTPS (DOH) server to use to resolve hostnames,
instead of using the default name resolver mechanism. The URL must be HTTPS.

If this option is used several times, the last one will be used.
.It Fl D  Ar <filename> | Fl -dump-header Ar <filename>
(HTTP FTP) Write the received protocol headers to the specified file.
.Pp
This option is handy to use when you want to store the headers that an
HTTP site sends to you. Cookies from the headers could then be read in
a second curl invocation by using the
.Fl b | -cookie
option! The
.Fl c | -cookie-jar
option is a better way to store cookies.
.Pp
When used in FTP, the FTP server response lines are considered being
"headers" and thus are saved there.
.Pp
If this option is used several times, the last one will be used.
.Pp
See also
.Fl o | -output .
.It Fl -egd-file Ar <file>
(TLS) Specify the path name to the Entropy Gathering Daemon
socket. The socket is used to seed the random engine for SSL
connections.
.Pp
See also
.Fl -random-file .
.It Fl -engine Ar <name>
(TLS) Select the OpenSSL crypto engine to use for cipher operations. Use \fI--engine\fP
list to print a list of build-time supported engines. Note that not all (or
none) of the engines may be available at run-time.
.It Fl -expect100-timeout Ar <seconds>
(HTTP) Maximum time in seconds that you allow curl to wait for a
100-continue response when curl emits an Expects: 100-continue header
in its request. By default curl will wait one second. This option
accepts decimal values! When curl stops waiting, it will continue as
if the response has been received.
.Pp
See also
.Fl -connect-timeout .
Added in 7.47.0.
.It Fl -fail-early
Fail and exit on the first detected transfer error.
.Pp
When curl is used to do multiple transfers on the command line, it
will attempt to operate on each given URL, one by one. By default, it
will ignore errors if there are more URLs given and the last URL's
success will determine the error code curl returns. So early failures
will be "hidden" by subsequent successful transfers.
.Pp
Using this option, curl will instead return an error on the first
transfer that fails, independent of the amount of URLs that are given
on the command line. This way, no transfer failures go undetected by
scripts and similar.
.Pp
This option is global and does not need to be specified for each use
of
.Fl : | -next .
.Pp
This option does not imply
.Fl f | -fail ,
which causes transfers to fail due to the server's HTTP status
code. You can combine the two options, however note
.Fl f | -fail
is not global and is therefore contained by
.Fl : | -next .
.Pp
Added in 7.52.0.
.It Fl f | -fail
(HTTP) Fail silently (no output at all) on server errors. This is
mostly done to better enable scripts etc to better deal with failed
attempts. In normal cases when an HTTP server fails to deliver a
document, it returns an HTML document stating so (which often also
describes why and more). This flag will prevent curl from outputting
that and return error 22.
.Pp
This method is not fail-safe and there are occasions where
non-successful response codes will slip through, especially when
authentication is involved (response codes 401 and 407).
.It Fl -false-start
(TLS) Tells curl to use false start during the TLS handshake. False
start is a mode where a TLS client will start sending application data
before verifying the server's Finished message, thus saving a round
trip when performing a full handshake.
.Pp
This is currently only implemented in the NSS and Secure Transport (on
iOS 7.0 or later, or OS X 10.9 or later) backends.
.Pp
Added in 7.42.0.
.It Fl -form-string Ar <name=string>
(HTTP SMTP IMAP) Similar to \fI-F, --form\fP except that the value
string for the named parameter is used literally. Leading \&'@' and
\&'<' characters, and the \&';type=' string in the value have no
special meaning. Use this in preference to
.Fl F | -form
if there's any possibility that the string value may accidentally
trigger the \&'@' or \&'<' features of
.Fl F | -form .
.Pp
See also
.Fl F | -form .
.It Fl F Ar <name=content> | -form Ar <name=content>
(HTTP SMTP IMAP) For HTTP protocol family, this lets curl emulate a
filled-in form in which a user has pressed the submit button. This
causes curl to POST data using the Content-Type multipart/form-data
according to RFC 2388.
.Pp
For SMTP and IMAP protocols, this is the mean to compose a multipart
mail message to transmit.
.Pp
This enables uploading of binary files etc. To force the 'content'
part to be a file, prefix the file name with an @ sign. To just get
the content part from a file, prefix the file name with the symbol
<. The difference between @ and < is then that @ makes a file get
attached in the post as a file upload, while the < makes a text field
and just get the contents for that text field from a file.
.Pp
Tell curl to read content from stdin instead of a file by using - as
filename. This goes for both @ and < constructs. When stdin is used,
the contents is buffered in memory first by curl to determine its size
and allow a possible resend.  Defining a part's data from a named
non-regular file (such as a named pipe or similar) is unfortunately
not subject to buffering and will be effectively read at transmission
time; since the full size is unknown before the transfer starts, such
data is sent as chunks by HTTP and rejected by IMAP.
.Pp
Example: send an image to an HTTP server, where \&'profile' is the
name of the form-field to which the file portrait.jpg will be the
input:
.Pp
.Dl curl -F profile=@portrait.jpg https://example.com/upload.cgi
.Pp
Example: send a your name and shoe size in two text fields to the server:
.Pp
.Dl curl -F name=John -F shoesize=11 https://example.com/
.Pp
Example: send a your essay in a text field to the server. Send it as a
plain text field, but get the contents for it from a local file:
.Pp
.Dl curl -F "story=<hugefile.txt" https://example.com/
.Pp
You can also tell curl what Content-Type to use by using 'type=', in a
manner similar to:
.Pp
.Dl curl -F "web=@index.html;type=text/html" example.com
.Pp
or
.Pp
.Dl curl -F "name=daniel;type=text/foo" example.com
.Pp
You can also explicitly change the name field of a file upload part by
setting filename=, like this:
.Pp
.Dl curl -F "file=@localfile;filename=nameinpost" example.com
.Pp
If filename/path contains ',' or ';', it must be quoted by double-quotes like:
.Pp
.Dl curl -F "file=@\\"localfile\\";filename=\\"nameinpost\\"" example.com
.Pp
or
.Pp
.Dl curl -F 'file=@"localfile";filename="nameinpost"' example.com
.Pp
Note that if a filename/path is quoted by double-quotes, any
double-quote or backslash within the filename must be escaped by
backslash.
.Pp
Quoting must also be applied to non-file data if it contains semicolons,
leading/trailing spaces or leading double quotes:
.Pp
.Dl curl -F 'colors="red; green; blue";type=text/x-myapp' example.com
.Pp
You can add custom headers to the field by setting headers=, like
.Pp
.Dl  curl -F "submit=OK;headers=\\"X-submit-type: OK\\"" example.com
.Pp
or
.Pp
.Dl  curl -F "submit=OK;headers=@headerfile" example.com
.Pp
The headers= keyword may appear more that once and above notes about
quoting apply. When headers are read from a file, Empty lines and
lines starting with '#' are comments and ignored; each header can be
folded by splitting between two words and starting the continuation
line with a space; embedded carriage-returns and trailing spaces are
stripped.  Here is an example of a header file contents:
.Bd -literal -offset indent compact
  # This file contain two headers.
  X-header-1: this is a header

  # The following header is folded.
  X-header-2: this is
   another header
.Ed
To support sending multipart mail messages, the syntax is extended as
follows:
.Bl -bullet -offset indent -compact
.It
name can be omitted: the equal sign is the first character of the argument,
.It
if data starts with '(', this signals to start a new multipart: it can
be followed by a content type specification.
.It
a multipart can be terminated with a '=)' argument.
.El
Example: the following command sends an SMTP mime e-mail consisting in
an inline part in two alternative formats: plain text and HTML. It
attaches a text file:
.Bd -literal -offset indent compact
 curl -F '=(;type=multipart/alternative' \\
         -F '=plain text message' \\
         -F '= <body>HTML message</body>;type=text/html' \\
      -F '=)' -F '=@textfile.txt' ...  smtp://example.com
.Ed
Data can be encoded for transfer using encoder=. Available encodings
are \fIbinary\fP and \fI8bit\fP that do nothing else than adding the
corresponding Content-Transfer-Encoding header, \fI7bit\fP that only
rejects 8-bit characters with a transfer error, \fIquoted-printable\fP
and \fIbase64\fP that encodes data according to the corresponding
schemes, limiting lines length to 76 characters.
.Pp
Example: send multipart mail with a quoted-printable text message and
a base64 attached file:
.Bd -literal -offset indent compact
 curl -F '=text message;encoder=quoted-printable' \\
      -F '=@localfile;encoder=base64' ... smtp://example.com
.Ed
See further examples and details in the MANUAL.
.Pp
This option can be used multiple times.
.Pp
This option overrides
.Fl d | -data
and
.Fl I | -head
and
.Fl T | -upload-file .
.It Fl -ftp-account Ar <data>
(FTP) When an FTP server asks for "account data" after user name and
password has been provided, this data is sent off using the ACCT
command.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.13.0.
.It Fl -ftp-alternative-to-user Ar <command>
(FTP) If authenticating with the USER and PASS commands fails, send
this command.  When connecting to Tumbleweed's Secure Transport server
over FTPS using a client certificate, using "SITE AUTH" will tell the
server to retrieve the username from the certificate.
.Pp
Added in 7.15.5.
.It Fl -ftp-create-dirs
(FTP SFTP) When an FTP or SFTP URL/operation uses a path that doesn't
currently exist on the server, the standard behavior of curl is to
fail. Using this option, curl will instead attempt to create missing
directories.
.Pp
See also
.Fl -create-dirs .
.It Fl -ftp-method Ar <method>
(FTP) Control what method curl should use to reach a file on an FTP(S)
server. The method argument should be one of the following alternatives:
.Bl -tag -width indent
.It multicwd
curl does a single CWD operation for each path part in the given
URL. For deep hierarchies this means very many commands. This is how
RFC 1738 says it should be done. This is the default but the slowest
behavior.
.It nocwd
curl does no CWD at all. curl will do SIZE, RETR, STOR etc and give a
full path to the server for all these commands. This is the fastest
behavior.
.It singlecwd
curl does one CWD with the full target directory and then operates on
the file \&"normally" (like in the multicwd case). This is somewhat
more standards compliant than 'nocwd' but without the full penalty
of 'multicwd'.
.El
Added in 7.15.1.
.It Fl -ftp-pasv
(FTP) Use passive mode for the data connection. Passive is the
internal default behavior, but using this option can be used to
override a previous
.Fl P | -ftp-port
option.
.Pp
If this option is used several times, only the first one is
used. Undoing an enforced passive really isn't doable but you must
then instead enforce the correct
.Fl P | -ftp-port
again.
.Pp
Passive mode means that curl will try the EPSV command first and then
PASV, unless
.Fl -disable-epsv
is used.
.Pp
See also
.Fl -disable-epsv .
Added in 7.11.0.
.It Fl P Ar <address> | -ftp-port Ar <address>
(FTP) Reverses the default initiator/listener roles when connecting
with FTP. This option makes curl use active mode. curl then tells the
server to connect back to the client's specified address and port,
while passive mode asks the server to setup an IP address and port for
it to connect to.
.Ar <address>
should be one of:
.Bl -tag -width indent
.It interface
e.g. "eth0" to specify which interface's IP address you want to use (Unix only)
.It IP address
e.g. "192.168.10.1" to specify the exact IP address
.It host name
e.g. "my.host.domain" to specify the machine
.It "-"
make curl pick the same IP address that is already used for the
control connection
.El
If this option is used several times, the last one will be
used. Disable the use of PORT with
.Fl -ftp-pasv .
Disable the attempt to use the EPRT command instead of PORT by using
.Fl -disable-eprt .
EPRT is really PORT++.
.Pp
Since 7.19.5, you can append \&":[start]-[end]\&" to the right of the
address, to tell curl what TCP port range to use. That means you
specify a port range, from a lower to a higher number. A single number
works as well, but do note that it increases the risk of failure since
the port may not be available.
.Pp
See also
.Fl -ftp-pasv
and
.Fl -disable-eprt .
.It Fl -ftp-pret
(FTP) Tell curl to send a PRET command before PASV (and EPSV). Certain
FTP servers, mainly drftpd, require this non-standard command for
directory listings as well as up and downloads in PASV mode.
.Pp
Added in 7.20.0.
.It Fl -ftp-skip-pasv-ip
(FTP) Tell curl to not use the IP address the server suggests in its
response to curl's PASV command when curl connects the data
connection. Instead curl will re-use the same IP address it already
uses for the control connection.
.Pp
This option has no effect if PORT, EPRT or EPSV is used instead of PASV.
.Pp
See also
.Fl -ftp-pasv .
Added in 7.14.2.
.It Fl -ftp-ssl-ccc-mode Ar <active/passive>
(FTP) Sets the CCC mode. The passive mode will not initiate the
shutdown, but instead wait for the server to do it, and will not reply
to the shutdown from the server. The active mode initiates the
shutdown and waits for a reply from the server.
.Pp
See also
.Fl -ftp-ssl-ccc .
Added in 7.16.2.
.It Fl -ftp-ssl-ccc
(FTP) Use CCC (Clear Command Channel) Shuts down the SSL/TLS layer
after authenticating. The rest of the control channel communication
will be unencrypted. This allows NAT routers to follow the FTP
transaction. The default mode is passive.
.Pp
See also
.Fl -ssl
and
.Fl -ftp-ssl-ccc-mode .
Added in 7.16.1.
.It Fl -ftp-ssl-control
(FTP) Require SSL/TLS for the FTP login, clear for transfer.  Allows
secure authentication, but non-encrypted data transfers for
efficiency.  Fails the transfer if the server doesn't support SSL/TLS.
.Pp
Added in 7.16.0.
.It Fl G | -get
When used, this option will make all data specified with
.Fl d ,
.Fl -data ,
.Fl -data-binary
or
.Fl -data-urlencode
to be used in an HTTP GET request instead of the POST request that
otherwise would be used. The data will be appended to the URL with
a '?' separator.
.Pp
If used in combination with
.Fl I | -head ,
the POST data will instead be appended to the URL with a HEAD request.
.Pp
If this option is used several times, only the first one is used. This
is because undoing a GET doesn't make sense, but you should then
instead enforce the alternative method you prefer.
.It Fl g | -globoff
This option switches off the "URL globbing parser". When you set this option,
you can specify URLs that contain the letters {}[] without having them being
interpreted by curl itself. Note that these letters are not normal legal URL
contents but they should be encoded according to the URI standard.
.It Fl -happy-eyeballs-timeout-ms Ar milliseconds
Happy eyeballs is an algorithm that attempts to connect to both IPv4
and IPv6 addresses for dual-stack hosts, preferring IPv6 first for the
number of milliseconds. If the IPv6 address cannot be connected to
within that time then a connection attempt is made to the IPv4 address
in parallel. The first connection to be established is the one that is
used.
.Pp
The range of suggested useful values is limited. Happy Eyeballs RFC
6555 says "It is RECOMMENDED that connection attempts be paced 150-250
ms apart to balance human factors against network load." libcurl
currently defaults to 200 ms. Firefox and Chrome currently default to
300 ms.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.59.0.
.It Fl -haproxy-protocol
(HTTP) Send a HAProxy PROXY protocol v1 header at the beginning of the
connection. This is used by some load balancers and reverse proxies to
indicate the client's true IP address and port.
.Pp
This option is primarily useful when sending test requests to a
service that expects this header.
.Pp
Added in 7.60.0.
.It Fl I | -head
(HTTP FTP FILE) Fetch the headers only! HTTP-servers feature the
command HEAD which this uses to get nothing but the header of a
document. When used on an FTP or FILE file, curl displays the file
size and last modification time only.
.It Fl H Ar <header/@file> | -header Ar <header/@file>
(HTTP) Extra header to include in the request when sending HTTP to a
server. You may specify any number of extra headers. Note that if you
should add a custom header that has the same name as one of the
internal ones curl would use, your externally set header will be used
instead of the internal one. This allows you to make even trickier
stuff than curl would normally do. You should not replace internally
set headers without knowing perfectly well what you're doing. Remove
an internal header by giving a replacement without content on the
right side of the colon, as in: -H \&"Host:". If you send the custom
header with no-value then its header must be terminated with a
semicolon, such as
.Fl H
\&"X-Custom-Header;" to send "X-Custom-Header:".
.Pp
curl will make sure that each header you add/replace is sent with the
proper end-of-line marker, you should thus \fBnot\fP add that as a
part of the header content: do not add newlines or carriage returns,
they will only mess things up for you.
.Pp
Starting in 7.55.0, this option can take an argument in @filename
style, which then adds a header for each line in the input file. Using
@- will make curl read the header file from stdin.
.Pp
See also the
.Fl A ,
.Fl -user-agent
and
.Fl e ,
.Fl -referer
options.
.Pp
Starting in 7.37.0, you need
.Fl -proxy-header
to send custom headers intended for a proxy.
.Pp
Example:
.Pp
.Dl curl -H "X-First-Name: Joe" http://example.com/
.Pp
\fBWARNING\fP: headers set with this option will be set in all
requests - even after redirects are followed, like when told with
.Fl L | -location .
This can lead to the header being sent to other hosts than the
original host, so sensitive headers should be used with caution
combined with following redirects.
.Pp
This option can be used multiple times to add/replace/remove multiple
headers.
.It Fl h | -help
Usage help. This lists all current command line options with a short
description.
.It Fl -hostpubmd5 Ar <md5>
(SFTP SCP) Pass a string containing 32 hexadecimal digits. The string
should be the 128 bit MD5 checksum of the remote host's public key,
curl will refuse the connection with the host unless the md5sums
match.
.Pp
Added in 7.17.1.
.It Fl -http0.9
(HTTP) Tells curl to be fine with HTTP version 0.9 response.
.Pp
HTTP/0.9 is a completely headerless response and therefore you can
also connect with this to non-HTTP servers and still get a response
since curl will simply transparently downgrade - if allowed.
.Pp
A future curl version will deny continuing if the response isn't at
least HTTP/1.0 unless this option is used.
.It Fl 0 | -http1.0
(HTTP) Tells curl to use HTTP version 1.0 instead of using its
internally preferred HTTP version.
.Pp
This option overrides
.Fl -http1.1
and
.Fl -http2 .
.It Fl -http1.1
(HTTP) Tells curl to use HTTP version 1.1.
.Pp
This option overrides
.Fl 0 | --http1.0
and
.Fl -http2 .
Added in 7.33.0.
.It Fl -http2-prior-knowledge
(HTTP) Tells curl to issue its non-TLS HTTP requests using HTTP/2
without HTTP/1.1 Upgrade. It requires prior knowledge that the server
supports HTTP/2 straight away. HTTPS requests will still do HTTP/2 the
standard way with negotiated protocol version in the TLS handshake.
.Pp
.Fl -http2-prior-knowledge
requires that the underlying libgnurl was built to support
HTTP/2. This option overrides
.Fl -http1.1
and
.Fl 0 | -http1.0
and
.Fl -http2 .
Added in 7.49.0.
.It Fl -http2
(HTTP) Tells curl to use HTTP version 2.

See also \fI--no-alpn\fP. \fI--http2\fP requires that the underlying libgnurl was built to support HTTP/2. This option overrides \fI--http1.1\fP and \fI-0, --http1.0\fP and \fI--http2-prior-knowledge\fP. Added in 7.33.0.
.It Fl -ignore-content-length
(FTP HTTP) For HTTP, Ignore the Content-Length header. This is particularly useful for
servers running Apache 1.x, which will report incorrect Content-Length for
files larger than 2 gigabytes.

For FTP (since 7.46.0), skip the RETR command to figure out the size before
downloading a file.
.It Fl i | -include
Include the HTTP response headers in the output. The HTTP response
headers can include things like server name, cookies, date of the
document, HTTP version and more...
.Pp
To view the request headers, consider the \fI-v, --verbose\fP option.
.Pp
See also \fI-v, --verbose\fP.
.It Fl k | -insecure
(TLS) By default, every SSL connection curl makes is verified to be
secure. This option allows curl to proceed and operate even for server
connections otherwise considered insecure.
.Pp
The server connection is verified by making sure the server's
certificate contains the right name and verifies successfully using
the cert store.
.Pp
See this online resource for further details:
.Lk https://curl.haxx.se/docs/sslcerts.html
.Pp
See also \fI--proxy-insecure\fP and \fI--cacert\fP.
.It Fl -interface Ar <name>
Perform an operation using a specified interface. You can enter
interface name, IP address or host name. An example could look like:
.Pp
.Dl curl --interface eth0:1 https://www.example.com/
.Pp
If this option is used several times, the last one will be used.
.Pp
On Linux it can be used to specify a VRF, but the binary needs to
either have CAP_NET_RAW or to be run as root. More information about
Linux VRF:
.Lk https://www.kernel.org/doc/Documentation/networking/vrf.txt
.Pp
See also \fI--dns-interface\fP.
.It Fl 4 | -ipv4
This option tells curl to resolve names to IPv4 addresses only, and
not for example try IPv6.
.Pp
See also \fI--http1.1\fP and \fI--http2\fP. This option overrides
\fI-6, --ipv6\fP.
.It Fl 6 | -ipv6
This option tells curl to resolve names to IPv6 addresses only, and
not for example try IPv4.
.Pp
See also \fI--http1.1\fP and \fI--http2\fP. This option overrides
\fI-4, --ipv4\fP.
.It Fl j | -junk-session-cookies
(HTTP) When curl is told to read cookies from a given file, this
option will make it discard all "session cookies". This will basically
have the same effect as if a new session is started. Typical browsers
always discard session cookies when they're closed down.
.Pp
See also \fI-b, --cookie\fP and \fI-c, --cookie-jar\fP.
.It Fl -keepalive-time Ar <seconds>
This option sets the time a connection needs to remain idle before
sending keepalive probes and the time between individual keepalive
probes. It is currently effective on operating systems offering the
TCP_KEEPIDLE and TCP_KEEPINTVL socket options (meaning Linux, recent
AIX, HP-UX and more). This option has no effect if
\fI--no-keepalive\fP is used.
.Pp
If this option is used several times, the last one will be used. If
unspecified, the option defaults to 60 seconds.
.Pp
Added in 7.18.0.
.It Fl -key-type Ar <type>
(TLS) Private key file type. Specify which type your \fI--key\fP
provided private key is. DER, PEM, and ENG are supported. If not
specified, PEM is assumed.
.Pp
If this option is used several times, the last one will be used.
.It Fl -key Ar <key>
(TLS SSH) Private key file name. Allows you to provide your private
key in this separate file. For SSH, if not specified, curl tries the
following candidates in order:
.Pa ~/.ssh/id_rsa ,
.Pa ~/.ssh/id_dsa ,
.Pa ./id_rsa ,
.Pa ./id_dsa .
.Pp
If curl is built against OpenSSL library, and the engine pkcs11 is
available, then a PKCS#11 URI (RFC 7512) can be used to specify a
private key located in a PKCS#11 device. A string beginning with
"pkcs11:" will be interpreted as a PKCS#11 URI. If a PKCS#11 URI is
provided, then the \fI--engine\fP option will be set as "pkcs11" if
none was provided and the \fI--key-type\fP option will be set as "ENG"
if none was provided.
.Pp
If this option is used several times, the last one will be used.
.It Fl -krb Ar <level>
(FTP) Enable Kerberos authentication and use. The level must be
entered and should be one of 'clear', 'safe', 'confidential',
or 'private'. Should you use a level that is not one of
these, 'private' will instead be used.
.Pp
If this option is used several times, the last one will be used.
.Pp
\fI--krb\fP requires that the underlying libgnurl was built to support
Kerberos.
.It Fl -libcurl Ar <file>
Append this option to any ordinary curl command line, and you will get
a libcurl-using C source code written to the file that does the
equivalent of what your command-line operation does!
.Pp
If this option is used several times, the last given file name will be
used.
.Pp
Added in 7.16.1.
.It Fl -limit-rate Ar <speed>
Specify the maximum transfer rate you want curl to use - for both
downloads and uploads. This feature is useful if you have a limited
pipe and you'd like your transfer not to use your entire bandwidth. To
make it slower than it otherwise would be.
.Pp
The given speed is measured in bytes/second, unless a suffix is
appended.  Appending 'k' or 'K' will count the number as
kilobytes, 'm' or 'M' makes it megabytes, while 'g' or 'G' makes it
gigabytes. Examples: 200K, 3m and 1G.
.Pp
If you also use the \fI-Y, --speed-limit\fP option, that option will
take precedence and might cripple the rate-limiting slightly, to help
keeping the speed-limit logic working.
.Pp
If this option is used several times, the last one will be used.
.It Fl l | -list-only
(FTP POP3) (FTP) When listing an FTP directory, this switch forces a
name-only view. This is especially useful if the user wants to
machine-parse the contents of an FTP directory since the normal
directory view doesn't use a standard look or format. When used like
this, the option causes a NLST command to be sent to the server
instead of LIST.
.Pp
Note: Some FTP servers list only files in their response to NLST; they
do not include sub-directories and symbolic links.
.Pp
(POP3) When retrieving a specific email from POP3, this switch forces
a LIST command to be performed instead of RETR. This is particularly
useful if the user wants to see if a specific message id exists on the
server and what size it is.
.Pp
Note: When combined with
.Fl X ,
.Fl -request ,
this option can be used to send an UIDL command instead, so the user
may use the email's unique identifier rather than it's message id to
make the request.
.Pp
Added in 7.21.5.
.It Fl -local-port Ar <num/range>
Set a preferred single number or range (FROM-TO) of local port numbers
to use for the connection(s).  Note that port numbers by nature are a
scarce resource that will be busy at times so setting this range to
something too narrow might cause unnecessary connection setup
failures.
.Pp
Added in 7.15.2.
.It Fl -location-trusted
(HTTP) Like \fI-L, --location\fP, but will allow sending the name +
password to all hosts that the site may redirect to. This may or may
not introduce a security breach if the site redirects you to a site to
which you'll send your authentication info (which is plaintext in the
case of HTTP Basic authentication).
.Pp
See also \fI-u, --user\fP.
.It Fl L | -location
(HTTP) If the server reports that the requested page has moved to a
different location (indicated with a Location: header and a 3XX
response code), this option will make curl redo the request on the new
place. If used together with \fI-i, --include\fP or \fI-I, --head\fP,
headers from all requested pages will be shown. When authentication is
used, curl only sends its credentials to the initial host. If a
redirect takes curl to a different host, it won't be able to intercept
the user+password. See also \fI--location-trusted\fP on how to change
this. You can limit the amount of redirects to follow by using the
\fI--max-redirs\fP option.
.Pp
When curl follows a redirect and the request is not a plain GET (for
example POST or PUT), it will do the following request with a GET if
the HTTP response was 301, 302, or 303. If the response code was any
other 3xx code, curl will re-send the following request using the same
unmodified method.
.Pp
You can tell curl to not change the non-GET request method to GET
after a 30x response by using the dedicated options for that:
\fI--post301\fP, \fI--post302\fP and \fI--post303\fP.
.It Fl -login-options Ar <options>
(IMAP POP3 SMTP) Specify the login options to use during server
authentication.
.Pp
You can use the login options to specify protocol specific options
that may be used during authentication. At present only IMAP, POP3 and
SMTP support login options. For more information about the login
options please see RFC 2384, RFC 5092 and IETF draft
draft-earhart-url-smtp-00.txt
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.34.0.
.It Fl -mail-auth Ar <address>
(SMTP) Specify a single address. This will be used to specify the
authentication address (identity) of a submitted message that is being
relayed to another server.
.Pp
See also \fI--mail-rcpt\fP and \fI--mail-from\fP. Added in 7.25.0.
.It Fl -mail-from Ar <address>
(SMTP) Specify a single address that the given mail should get sent
from.
.Pp
See also \fI--mail-rcpt\fP and \fI--mail-auth\fP. Added in 7.20.0.
.It Fl -mail-rcpt Ar <address>
(SMTP) Specify a single address, user name or mailing list
name. Repeat this option several times to send to multiple recipients.
.Pp
When performing a mail transfer, the recipient should specify a valid
email address to send the mail to.
.Pp
When performing an address verification (VRFY command), the recipient
should be specified as the user name or user name and domain (as per
Section 3.5 of RFC5321). (Added in 7.34.0)
.Pp
When performing a mailing list expand (EXPN command), the recipient
should be specified using the mailing list name, such as "Friends" or
"London-Office".  (Added in 7.34.0)
.Pp
Added in 7.20.0.
.It Fl M | -manual
Manual. Display the huge help text.
.It Fl -max-filesize Ar <bytes>
Specify the maximum size (in bytes) of a file to download. If the file
requested is larger than this value, the transfer will not start and
curl will return with exit code 63.
.Pp
A size modifier may be used. For example, Appending 'k' or 'K' will
count the number as kilobytes, 'm' or 'M' makes it megabytes,
while 'g' or 'G' makes it gigabytes. Examples: 200K, 3m and 1G. (Added
in 7.58.0)
.Pp
\fBNOTE:\fP The file size is not always known prior to download, and
for such files this option has no effect even if the file transfer
ends up being larger than this given limit. This concerns both FTP and
HTTP transfers.
.Pp
See also \fI--limit-rate\fP.
.It Fl -max-redirs Ar <num>
(HTTP) Set maximum number of redirection-followings allowed. When
\fI-L, --location\fP is used, is used to prevent curl from following
redirections too much. By default, the limit is set to 50
redirections. Set this option to -1 to make it unlimited.
.Pp
If this option is used several times, the last one will be used.
.It Fl m Ar seconds | Fl -max-time seconds
Maximum time in seconds that you allow the whole operation to take.
This is useful for preventing your batch jobs from hanging for hours
due to slow networks or links going down.  Since 7.32.0, this option
accepts decimal values, but the actual timeout will decrease in
accuracy as the specified timeout increases in decimal precision.
.Pp
If this option is used several times, the last one will be used.
.Pp
See also \fI--connect-timeout\fP.
.It Fl -metalink
This option can tell curl to parse and process a given URI as Metalink
file (both version 3 and 4 (RFC 5854) are supported) and make use of
the mirrors listed within for failover if there are errors (such as
the file or server not being available). It will also verify the hash
of the file after the download completes. The Metalink file itself is
downloaded and processed in memory and not stored in the local file
system.
.Pp
Example to use a remote Metalink file:
.Pp
.Dl curl --metalink http://www.example.com/example.metalink
.Pp
To use a Metalink file in the local file system, use FILE protocol
(file://):
.Pp
.Dl curl --metalink file://example.metalink
.Pp
Please note that if FILE protocol is disabled, there is no way to use
a local Metalink file at the time of this writing. Also note that if
\fI--metalink\fP and \fI-i, --include\fP are used together, --include
will be ignored. This is because including headers in the response
will break Metalink parser and if the headers are included in the file
described in Metalink file, hash check will fail.
.Pp
\fI--metalink\fP requires that the underlying libgnurl was built to
support metalink. Added in 7.27.0.
.It Fl -negotiate
(HTTP) Enables Negotiate (SPNEGO) authentication.
.Pp
This option requires a library built with GSS-API or SSPI support. Use
\fI-V, --version\fP to see if your curl supports GSS-API/SSPI or
SPNEGO.
.Pp
When using this option, you must also provide a fake \fI-u, --user\fP
option to activate the authentication code properly. Sending a '-u :'
is enough as the user name and password from the \fI-u, --user\fP
option aren't actually used.
.Pp
If this option is used several times, only the first one is used.
.Pp
See also \fI--basic\fP and \fI--ntlm\fP and \fI--anyauth\fP and
\fI--proxy-negotiate\fP.
.It Fl -netrc-file Ar filename
This option is similar to \fI-n, --netrc\fP, except that you provide
the path (absolute or relative) to the netrc file that curl should
use.  You can only specify one netrc file per invocation. If several
\fI--netrc-file\fP options are provided, the last one will be used.
.Pp
It will abide by \fI--netrc-optional\fP if specified.
.Pp
This option overrides \fI-n, --netrc\fP. Added in 7.21.5.
.It Fl -netrc-optional
Very similar to \fI-n, --netrc\fP, but this option makes the .netrc
usage \fBoptional\fP and not mandatory as the \fI-n, --netrc\fP option
does.
.Pp
See also \fI--netrc-file\fP. This option overrides \fI-n, --netrc\fP.
.It Fl n | -netrc
Makes curl scan the \fI.netrc\fP (\fI_netrc\fP on Windows) file in the
user's home directory for login name and password. This is typically
used for FTP on Unix. If used with HTTP, curl will enable user
authentication. See \fInetrc(5)\fP \fIftp(1)\fP for details on the
file format. Curl will not complain if that file doesn't have the
right permissions (it should not be either world- or
group-readable). The environment variable "HOME" is used to find the
home directory.
.Pp
A quick and very simple example of how to setup a \fI.netrc\fP to
allow curl to FTP to the machine host.domain.com with user name
\&'myself' and password \&'secret' should look similar to:
.Pp
.Dl "machine host.domain.com login myself password secret"
.It Fl : | -next
Tells curl to use a separate operation for the following URL and
associated options. This allows you to send several URL requests, each
with their own specific options, for example, such as different user
names or custom requests for each.
.Pp
\fI-:, --next\fP will reset all local options and only global ones
will have their values survive over to the operation following the
\fI-:, --next\fP instruction. Global options include \fI-v,
--verbose\fP, \fI--trace\fP, \fI--trace-ascii\fP and
\fI--fail-early\fP.
.Pp
For example, you can do both a GET and a POST in a single command line:
.Pp
.Dl curl www1.example.com --next -d postthis www2.example.com
.Pp
Added in 7.36.0.
.It Fl -no-alpn
(HTTPS) Disable the ALPN TLS extension. ALPN is enabled by default if
libcurl was built with an SSL library that supports ALPN. ALPN is used
by a libcurl that supports HTTP/2 to negotiate HTTP/2 support with the
server during https sessions.
.Pp
See also \fI--no-npn\fP and \fI--http2\fP. \fI--no-alpn\fP requires
that the underlying libgnurl was built to support TLS. Added in
7.36.0.
.It Fl N | -no-buffer
Disables the buffering of the output stream. In normal work
situations, curl will use a standard buffered output stream that will
have the effect that it will output the data in chunks, not
necessarily exactly when the data arrives.  Using this option will
disable that buffering.
.Pp
Note that this is the negated option name documented. You can thus use
--buffer to enforce the buffering.
.It Fl -no-keepalive
Disables the use of keepalive messages on the TCP connection. curl
otherwise enables them by default.
.Pp
Note that this is the negated option name documented. You can thus use
--keepalive to enforce keepalive.
.It Fl -no-npn
(HTTPS) Disable the NPN TLS extension. NPN is enabled by default if
libcurl was built with an SSL library that supports NPN. NPN is used
by a libcurl that supports HTTP/2 to negotiate HTTP/2 support with the
server during https sessions.
.Pp
See also \fI--no-alpn\fP and \fI--http2\fP. \fI--no-npn\fP requires
that the underlying libgnurl was built to support TLS. Added in
7.36.0.
.It Fl -no-sessionid
(TLS) Disable curl's use of SSL session-ID caching.  By default all
transfers are done using the cache. Note that while nothing should
ever get hurt by attempting to reuse SSL session-IDs, there seem to be
broken SSL implementations in the wild that may require you to disable
this in order for you to succeed.
.Pp
Note that this is the negated option name documented. You can thus use
--sessionid to enforce session-ID caching.
.Pp
Added in 7.16.0.
.It Fl -noproxy Ar no-proxy-list
Comma-separated list of hosts which do not use a proxy, if one is
specified.  The only wildcard is a single * character, which matches
all hosts, and effectively disables the proxy. Each name in this list
is matched as either a domain which contains the hostname, or the
hostname itself. For example, local.com would match local.com,
local.com:80, and www.local.com, but not www.notlocal.com.
.Pp
Since 7.53.0, This option overrides the environment variables that
disable the proxy. If there's an environment variable disabling a
proxy, you can set noproxy list to \&"" to override it.
.Pp
Added in 7.19.4.
.It Fl -ntlm-wb
(HTTP) Enables NTLM much in the style \fI--ntlm\fP does, but hand over
the authentication to the separate binary ntlmauth application that is
executed when needed.
.Pp
See also \fI--ntlm\fP and \fI--proxy-ntlm\fP.
.It Fl -ntlm
(HTTP) Enables NTLM authentication. The NTLM authentication method was
designed by Microsoft and is used by IIS web servers. It is a
proprietary protocol, reverse-engineered by clever people and
implemented in curl based on their efforts. This kind of behavior
should not be endorsed, you should encourage everyone who uses NTLM to
switch to a public and documented authentication method instead, such
as Digest.
.Pp
If you want to enable NTLM for your proxy authentication, then use
\fI--proxy-ntlm\fP.
.Pp
If this option is used several times, only the first one is used.
.Pp
See also \fI--proxy-ntlm\fP. \fI--ntlm\fP requires that the underlying
libgnurl was built to support TLS. This option overrides \fI--basic\fP
and \fI--negotiate\fP and \fI--digest\fP and \fI--anyauth\fP.
.It Fl -oauth2-bearer Ar token
(IMAP POP3 SMTP) Specify the Bearer Token for OAUTH 2.0 server
authentication. The Bearer Token is used in conjunction with the user
name which can be specified as part of the \fI--url\fP or \fI-u,
--user\fP options.
.Pp
The Bearer Token and user name are formatted according to RFC 6750.
.Pp
If this option is used several times, the last one will be used.
.It Fl o Ar FILE | Fl -output Ar FILE
Write output to
.Ar FILE
instead of stdout. If you are using {} or [] to fetch multiple
documents, you can use '#' followed by a number in the
.Ar file
specifier. That variable will be replaced with the current string for
the URL being fetched. Like in:
.Pp
.Dl curl http://{one,two}.example.com -o "file_#1.txt"
.Pp
or use several variables like:
.Pp
.Dl curl http://{site,host}.host[1-5].com -o "#1_#2"
.Pp
You may use this option as many times as the number of URLs you
have. For example, if you specify two URLs on the same command line,
you can use it like this:
.Pp
.Dl  curl -o aa example.com -o bb example.net
.Pp
and the order of the -o options and the URLs doesn't matter, just that
the first -o is for the first URL and so on, so the above command line
can also be written as
.Pp
.Dl  curl example.com example.net -o aa -o bb
.Pp
See also the \fI--create-dirs\fP option to create the local
directories dynamically. Specifying the output as '-' (a single dash)
will force the output to be done to stdout.
.Pp
See also \fI-O, --remote-name\fP and \fI--remote-name-all\fP and
\fI-J, --remote-header-name\fP.
.It Fl -pass Ar phrase
(SSH TLS) Passphrase for the private key
.Pp
If this option is used several times, the last one will be used.
.It Fl -path-as-is
Tell curl to not handle sequences of /../ or /./ in the given URL
path. Normally curl will squash or merge them according to standards
but with this option set you tell it not to do that.
.Pp
Added in 7.42.0.
.It Fl -pinnedpubkey Ar <hashes>
(TLS) Tells curl to use the specified public key file (or hashes) to
verify the peer. This can be a path to a file which contains a single
public key in PEM or DER format, or any number of base64 encoded
sha256 hashes preceded by \'sha256//\' and separated by \';\'
.Pp
When negotiating a TLS or SSL connection, the server sends a
certificate indicating its identity. A public key is extracted from
this certificate and if it does not exactly match the public key
provided to this option, curl will abort the connection before sending
or receiving any data.
.Pp
PEM/DER support:
.Bl -bullet -offset indent -compact
.It
7.39.0: OpenSSL, GnuTLS and GSKit
.It
7.43.0: NSS and wolfSSL/CyaSSL
.It
7.47.0: mbedtls
.It
7.49.0: PolarSSL
.El
sha256 support:
.Bl -bullet -offset indent -compact
.It
7.44.0: OpenSSL, GnuTLS, NSS and wolfSSL/CyaSSL.
.It
7.47.0: mbedtls
.It
7.49.0: PolarSSL
.El
Other SSL backends not supported.
.Pp
If this option is used several times, the last one will be used.
.It Fl -post301
(HTTP) Tells curl to respect RFC 7231/6.4.2 and not convert POST
requests into GET requests when following a 301 redirection. The
non-RFC behaviour is ubiquitous in web browsers, so curl does the
conversion by default to maintain consistency. However, a server may
require a POST to remain a POST after such a redirection.
This option is meaningful only when using
.Fl L ,
.Fl -location .
.Pp
See also
.Fl -post302
and
.Fl -post303
and
.Fl L ,
.Fl -location .
Added in 7.17.1.
.It Fl -post302
(HTTP) Tells curl to respect RFC 7231/6.4.3 and not convert POST
requests into GET requests when following a 302 redirection. The
non-RFC behaviour is ubiquitous in web browsers, so curl does the
conversion by default to maintain consistency. However, a server may
require a POST to remain a POST after such a redirection. This option
is meaningful only when using
.Fl L ,
.Fl -location .
.Pp
See also \fI--post301\fP and \fI--post303\fP and \fI-L,
--location\fP. Added in 7.19.1.
.It Fl -post303
(HTTP) Tells curl to violate RFC 7231/6.4.4 and not convert POST
requests into GET requests when following 303 redirections. A server
may require a POST to remain a POST after a 303 redirection. This
option is meaningful only when using \fI-L, --location\fP.
.Pp
See also \fI--post302\fP and \fI--post301\fP and \fI-L,
--location\fP. Added in 7.26.0.
.It Fl -preproxy Ar [protocol://]host[:port]
Use the specified SOCKS proxy before connecting to an HTTP or HTTPS
\fI-x, --proxy\fP. In such a case curl first connects to the SOCKS
proxy and then connects (through SOCKS) to the HTTP or HTTPS
proxy. Hence pre proxy.
.Pp
The pre proxy string should be specified with a protocol:// prefix to
specify alternative proxy protocols. Use socks4://, socks4a://,
socks5:// or socks5h:// to request the specific SOCKS version to be
used. No protocol specified will make curl default to SOCKS4.
.Pp
If the port number is not specified in the proxy string, it is assumed
to be 1080.
.Pp
User and password that might be provided in the proxy string are URL
decoded by curl. This allows you to pass in special characters such as
@ by using %40 or pass in a colon with %3a.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.52.0.
.It Fl # | -progress-bar
Make curl display transfer progress as a simple progress bar instead
of the standard, more informational, meter.
.Pp
This progress bar draws a single line of '#' characters across the
screen and shows a percentage if the transfer size is known. For
transfers without a known size, there will be space ship (-=o=-) that
moves back and forth but only while data is being transferred, with a
set of flying hash sign symbols on top.
.It Fl -proto-default Ar <protocol>
Tells curl to use \fIprotocol\fP for any URL missing a scheme name.
.Pp
Example:
.Pp
.Dl curl --proto-default https ftp.mozilla.org
.Pp
An unknown or unsupported protocol causes error
\fICURLE_UNSUPPORTED_PROTOCOL\fP (1).
.Pp
This option does not change the default proxy protocol (http).
.Pp
Without this option curl would make a guess based on the host, see
\fI--url\fP for details.
.Pp
Added in 7.45.0.
.It Fl -proto-redir Ar <protocols>
Tells curl to limit what protocols it may use on redirect. Protocols
denied by \fI--proto\fP are not overridden by this option. See --proto
for how protocols are represented.
.Pp
Example, allow only HTTP and HTTPS on redirect:
.Pp
.Dl curl --proto-redir -all,http,https http://example.com
.Pp
By default curl will allow all protocols on redirect except several
disabled for security reasons: Since 7.19.4 FILE and SCP are disabled,
and since 7.40.0 SMB and SMBS are also disabled. Specifying \fIall\fP
or \fI+all\fP enables all protocols on redirect, including those
disabled for security.
.Pp
Added in 7.20.2.
.It Fl -proto Ar <protocols>
Tells curl to limit what protocols it may use in the
transfer. Protocols are evaluated left to right, are comma separated,
and are each a protocol name or
.Ar all ,
optionally prefixed by zero or more modifiers. Available modifiers are:
.Bl -tag -width indent
.It +
Permit this protocol in addition to protocols already permitted (this
is the default if no modifier is used).
.It -
Deny this protocol, removing it from the list of protocols already
permitted.
.It =
Permit only this protocol (ignoring the list already permitted),
though subject to later modification by subsequent entries in the
comma separated list.
.El
.Pp
For example:
.Pp
.Dl \fI--proto\fP -ftps
.Pp
uses the default protocols, but disables ftps
.Pp
.Dl \fI--proto\fP -all,https,+http
.Pp
only enables http and https
.Pp
.Dl \fI--proto\fP =http,https
.Pp
also only enables http and https
.Pp
Unknown protocols produce a warning. This allows scripts to safely
rely on being able to disable potentially dangerous protocols, without
relying upon support for that protocol being built into curl to avoid
an error.
.Pp
This option can be used multiple times, in which case the effect is
the same as concatenating the protocols into one instance of the
option.
.Pp
See also \fI--proto-redir\fP and \fI--proto-default\fP. Added in
7.20.2.
.It Fl -proxy-anyauth
Tells curl to pick a suitable authentication method when communicating
with the given HTTP proxy. This might cause an extra request/response
round-trip.
.Pp
See also \fI-x, --proxy\fP and \fI--proxy-basic\fP and
\fI--proxy-digest\fP. Added in 7.13.2.
.It Fl -proxy-basic
Tells curl to use HTTP Basic authentication when communicating with
the given proxy. Use \fI--basic\fP for enabling HTTP Basic with a
remote host. Basic is the default authentication method curl uses with
proxies.
.Pp
See also \fI-x, --proxy\fP and \fI--proxy-anyauth\fP and
\fI--proxy-digest\fP.
.It Fl -proxy-cacert Ar <file>
Same as
.Fl -cacert
but used in HTTPS proxy context.
.Pp
See also
.Fl -proxy-capath
and
.Fl -cacert
and
.Fl -capath
and
.Fl x ,
.Fl -proxy .
Added in 7.52.0.
.It Fl -proxy-capath Ar <dir>
Same as
.Fl -capath
but used in HTTPS proxy context.
.Pp
See also
.Fl -proxy-cacert
and
.Fl x ,
.Fl -proxy
and
.Fl -capath .
Added in 7.52.0.
.It Fl -proxy-cert-type Ar <type>
Same as
.Fl -cert-type
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-cert Ar <cert[:passwd]>
Same as
.Fl E ,
.Fl -cert
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-ciphers Ar <list>
Same as
.Fl -ciphers
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-crlfile Ar <file>
Same as
.Fl -crlfile
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-digest
Tells curl to use HTTP Digest authentication when communicating with
the given proxy. Use
.Fl -digest
for enabling HTTP Digest with a remote host.
.Pp
See also
.Fl x ,
.Fl -proxy
and
.Fl -proxy-anyauth
and
.Fl -proxy-basic .
.It Fl -proxy-header Ar <header/@file>
(HTTP) Extra header to include in the request when sending HTTP to a
proxy. You may specify any number of extra headers. This is the
equivalent option to
.Fl H ,
.Fl -header
but is for proxy communication only like in CONNECT requests when you
want a separate header sent to the proxy to what is sent to the actual
remote host.
.Pp
curl will make sure that each header you add/replace is sent with the
proper end-of-line marker, you should thus \fBnot\fP add that as a
part of the header content: do not add newlines or carriage returns,
they will only mess things up for you.
.Pp
Headers specified with this option will not be included in requests
that curl knows will not be sent to a proxy.
.Pp
Starting in 7.55.0, this option can take an argument in @filename
style, which then adds a header for each line in the input file. Using
@- will make curl read the header file from stdin.
.Pp
This option can be used multiple times to add/replace/remove multiple
headers.
.Pp
Added in 7.37.0.
.It Fl -proxy-insecure
Same as
.Fl k ,
.Fl -insecure
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-key-type Ar <type>
Same as
.Fl -key-type
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-key Ar <key>
Same as
.Fl -key
but used in HTTPS proxy context.
.It Fl -proxy-negotiate
Tells curl to use HTTP Negotiate (SPNEGO) authentication when
communicating with the given proxy. Use
.Fl -negotiate
for enabling HTTP Negotiate (SPNEGO) with a remote host.
.Pp
See also
.Fl -proxy-anyauth
and
.Fl -proxy-basic .
Added in 7.17.1.
.It Fl -proxy-ntlm
Tells curl to use HTTP NTLM authentication when communicating with the
given proxy. Use
.Fl -ntlm
for enabling NTLM with a remote host.
.Pp
See also
.Fl -proxy-negotiate
and
.Fl -proxy-anyauth .
.It Fl -proxy-pass Ar <phrase>
Same as
.Fl -pass
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-pinnedpubkey Ar <hashes>
(TLS) Tells curl to use the specified public key file (or hashes) to
verify the proxy. This can be a path to a file which contains a single
public key in PEM or DER format, or any number of base64 encoded
sha256 hashes preceded by \'sha256//\' and separated by \';\'
.Pp
When negotiating a TLS or SSL connection, the server sends a
certificate indicating its identity. A public key is extracted from
this certificate and if it does not exactly match the public key
provided to this option, curl will abort the connection before sending
or receiving any data.
.Pp
If this option is used several times, the last one will be used.
.It Fl -proxy-service-name Ar <name>
This option allows you to change the service name for proxy
negotiation.
.Pp
Added in 7.43.0.
.It Fl -proxy-ssl-allow-beast
Same as
.Fl -ssl-allow-beast
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-tls13-ciphers Ar <ciphersuite list>
(TLS) Specifies which cipher suites to use in the connection to your
HTTPS proxy when it negotiates TLS 1.3. The list of ciphers suites
must specify valid ciphers. Read up on TLS 1.3 cipher suite details on
this URL:
.Pp
.Dl https://curl.haxx.se/docs/ssl-ciphers.html
.Pp
If this option is used several times, the last one will be used.
.It Fl -proxy-tlsauthtype Ar <type>
Same as
.Fl -tlsauthtype
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-tlspassword Ar <string>
Same as
.Fl -tlspassword
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-tlsuser Ar <name>
Same as
.Fl -tlsuser
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl -proxy-tlsv1
Same as
.Fl 1 ,
.Fl -tlsv1
but used in HTTPS proxy context.
.Pp
Added in 7.52.0.
.It Fl U Ar <user:password> | Fl -proxy-user Ar <user:password>
Specify the user name and password to use for proxy authentication.
.Pp
If you use a Windows SSPI-enabled curl binary and do either Negotiate
or NTLM authentication then you can tell curl to select the user name
and password from your environment by specifying a single colon with
this option: "-U :".
.Pp
On systems where it works, curl will hide the given option argument
from process listings. This is not enough to protect credentials from
possibly getting seen by other users on the same system as they will
still be visible for a brief moment before cleared. Such sensitive
data should be retrieved from a file instead or similar and never used
in clear text in a command line.
.Pp
If this option is used several times, the last one will be used.
.It Fl x  Ar [protocol://]host[:port] | -proxy Ar [protocol://]host[:port]
Use the specified proxy.
.Pp
The proxy string can be specified with a protocol:// prefix. No
protocol specified or http:// will be treated as HTTP proxy. Use
socks4://, socks4a://, socks5:// or socks5h:// to request a specific
SOCKS version to be used.  (The protocol support was added in curl
7.21.7)
.Pp
HTTPS proxy support via https:// protocol prefix was added in 7.52.0
for OpenSSL, GnuTLS and NSS.
.Pp
Unrecognized and unsupported proxy protocols cause an error since
7.52.0.  Prior versions may ignore the protocol and use http://
instead.
.Pp
If the port number is not specified in the proxy string, it is assumed
to be 1080.
.Pp
This option overrides existing environment variables that set the
proxy to use. If there's an environment variable setting a proxy, you
can set proxy to \&"" to override it.
.Pp
All operations that are performed over an HTTP proxy will
transparently be converted to HTTP. It means that certain protocol
specific operations might not be available. This is not the case if
you can tunnel through the proxy, as one with the
.Fl p ,
.Fl -proxytunnel
option.
.Pp
User and password that might be provided in the proxy string are URL
decoded by curl. This allows you to pass in special characters such as
@ by using %40 or pass in a colon with %3a.
.Pp
The proxy host can be specified the exact same way as the proxy
environment variables, including the protocol prefix (http://) and the
embedded user + password.
.Pp
If this option is used several times, the last one will be used.
.It Fl -proxy1.0 Ar <host[:port]>
Use the specified HTTP 1.0 proxy. If the port number is not specified,
it is assumed at port 1080.
.Pp
The only difference between this and the HTTP proxy option
.Fl x ,
.Fl -proxy ,
is that attempts to use CONNECT through the proxy will specify an HTTP
1.0 protocol instead of the default HTTP 1.1.
.It Fl p | -proxytunnel
When an HTTP proxy is used
.Fl x ,
.Fl -proxy ,
this option will make curl tunnel through the proxy. The tunnel
approach is made with the HTTP proxy CONNECT request and requires that
the proxy allows direct connect to the remote port number curl wants
to tunnel through to.
.Pp
To suppress proxy CONNECT response headers when curl is set to output
headers use
.Fl -suppress-connect-headers .
.Pp
See also
.Fl x ,
.Fl -proxy .
.It Fl -pubkey Ar <key>
(SFTP SCP) Public key file name. Allows you to provide your public key
in this separate file.
.Pp
If this option is used several times, the last one will be used.
.Pp
(As of 7.39.0, curl attempts to automatically extract the public key
from the private key file, so passing this option is generally not
required. Note that this public key extraction requires libcurl to be
linked against a copy of libssh2 1.2.8 or higher that is itself linked
against OpenSSL.)
.It Fl Q | -quote
(FTP SFTP) Send an arbitrary command to the remote FTP or SFTP
server. Quote commands are sent BEFORE the transfer takes place (just
after the initial PWD command in an FTP transfer, to be exact). To
make commands take place after a successful transfer, prefix them with
a dash '-'.  To make commands be sent after curl has changed the
working directory, just before the transfer command(s), prefix the
command with a '+' (this is only supported for FTP). You may specify
any number of commands.
.Pp
If the server returns failure for one of the commands, the entire
operation will be aborted. You must send syntactically correct FTP
commands as RFC 959 defines to FTP servers, or one of the commands
listed below to SFTP servers.
.Pp
This option can be used multiple times. When speaking to an FTP
server, prefix the command with an asterisk (*) to make curl continue
even if the command fails as by default curl will stop at first
failure.
.Pp
SFTP is a binary protocol. Unlike for FTP, curl interprets SFTP quote
commands itself before sending them to the server.  File names may be
quoted shell-style to embed spaces or special characters.  Following
is the list of all supported SFTP quote commands:
.Bl -tag -width indent
.It chgrp group file
The chgrp command sets the group ID of the file named by the file
operand to the group ID specified by the group operand. The group
operand is a decimal integer group ID.
.It chmod mode file
The chmod command modifies the file mode bits of the specified
file. The mode operand is an octal integer mode number.
.It chown user file
The chown command sets the owner of the file named by the file operand
to the user ID specified by the user operand. The user operand is a
decimal integer user ID.
.It ln source_file target_file
The ln and symlink commands create a symbolic link at the target_file
location pointing to the source_file location.
.It mkdir directory_name
The mkdir command creates the directory named by the directory_name
operand.
.It pwd
The pwd command returns the absolute pathname of the current working
directory.
.It rename source target
The rename command renames the file or directory named by the source
operand to the destination path named by the target operand.
.It rm file
The rm command removes the file specified by the file operand.
.It rmdir directory
The rmdir command removes the directory entry specified by the directory
operand, provided it is empty.
.It symlink source_file target_file
See ln.
.El
.It Fl -random-file Ar <file>
Specify the path name to file containing what will be considered as random
data. The data may be used to seed the random engine for SSL connections.
See also the
.Fl -egd-file
option.
.It Fl r  Ar <range> | Fl -range Ar <range>
(HTTP FTP SFTP FILE) Retrieve a byte range (i.e. a partial document)
from an HTTP/1.1, FTP or SFTP server or a local FILE. Ranges can be
specified in a number of ways.
.RS
.TP 10
.B 0-499
specifies the first 500 bytes
.TP
.B 500-999
specifies the second 500 bytes
.TP
.B -500
specifies the last 500 bytes
.TP
.B 9500-
specifies the bytes from offset 9500 and forward
.TP
.B 0-0,-1
specifies the first and last byte only(*)(HTTP)
.TP
.B 100-199,500-599
specifies two separate 100-byte ranges(*) (HTTP)
.RE
.It Fl
(*) = NOTE that this will cause the server to reply with a multipart
response!
.Pp
Only digit characters (0-9) are valid in the 'start' and 'stop' fields
of the \&'start-stop' range syntax. If a non-digit character is given
in the range, the server's response will be unspecified, depending on
the server's configuration.
.Pp
You should also be aware that many HTTP/1.1 servers do not have this
feature enabled, so that when you attempt to get a range, you'll
instead get the whole document.
.Pp
FTP and SFTP range downloads only support the simple 'start-stop'
syntax (optionally with one of the numbers omitted). FTP use depends
on the extended FTP command SIZE.
.Pp
If this option is used several times, the last one will be used.
.It Fl -raw
(HTTP) When used, it disables all internal HTTP decoding of content or
transfer encodings and instead makes them passed on unaltered, raw.
.Pp
Added in 7.16.2.
.It Fl e | -referer Ar <URL>
(HTTP) Sends the "Referrer Page" information to the HTTP server. This
can also be set with the
.Fl H ,
.Fl -header
flag of course. When used with
.Fl L ,
.Fl -location
you can append ";auto" to the
.Fl e ,
.Fl -referer
URL to make curl automatically set the previous URL when it follows a
Location: header. The \&";auto" string can be used alone, even if you
don't set an initial
.Fl e ,
.Fl -referer .
.Pp
If this option is used several times, the last one will be used.
.Pp
See also
.Fl A ,
.Fl -user-agent
and
.Fl H ,
.Fl -header .
.It Fl J | -remote-header-name
(HTTP) This option tells the \fI-O, --remote-name\fP option to use the
server-specified Content-Disposition filename instead of extracting a
filename from the URL.
.Pp
If the server specifies a file name and a file with that name already
exists in the current working directory it will not be overwritten and
an error will occur. If the server doesn't specify a file name then
this option has no effect.
.Pp
There's no attempt to decode %-sequences (yet) in the provided file
name, so this option may provide you with rather unexpected file
names.
.Pp
\fBWARNING\fP: Exercise judicious use of this option, especially on
Windows. A rogue server could send you the name of a DLL or other file
that could possibly be loaded automatically by Windows or some third
party software.
.It Fl -remote-name-all
This option changes the default action for all given URLs to be dealt
with as if \fI-O, --remote-name\fP were used for each one. So if you
want to disable that for a specific URL after \fI--remote-name-all\fP
has been used, you must use "-o -" or --no-remote-name.
.Pp
Added in 7.19.0.
.It Fl O | -remote-name
Write output to a local file named like the remote file we get. (Only
the file part of the remote file is used, the path is cut off.)
.Pp
The file will be saved in the current working directory. If you want
the file saved in a different directory, make sure you change the
current working directory before invoking curl with this option.
.Pp
The remote file name to use for saving is extracted from the given
URL, nothing else, and if it already exists it will be overwritten. If
you want the server to be able to choose the file name refer to \fI-J,
--remote-header-name\fP which can be used in addition to this
option. If the server chooses a file name and that name already exists
it will not be overwritten.
.Pp
There is no URL decoding done on the file name. If it has %20 or other
URL encoded parts of the name, they will end up as-is as file name.
.Pp
You may use this option as many times as the number of URLs you have.
.It Fl R | -remote-time
When used, this will make curl attempt to figure out the timestamp of
the remote file, and if that is available make the local file get that
same timestamp.
.It Fl -request-target
(HTTP) Tells curl to use an alternative "target" (path) instead of
using the path as provided in the URL. Particularly useful when
wanting to issue HTTP requests without leading slash or other data
that doesn't follow the regular URL pattern, like "OPTIONS *".
.Pp
Added in 7.55.0.
.It Fl X Ar command | -request Ar <command>
(HTTP) Specifies a custom request method to use when communicating
with the HTTP server.  The specified request method will be used
instead of the method otherwise used (which defaults to GET). Read the
HTTP 1.1 specification for details and explanations. Common additional
HTTP requests include PUT and DELETE, but related technologies like
WebDAV offers PROPFIND, COPY, MOVE and more.
.Pp
Normally you don't need this option. All sorts of GET, HEAD, POST and
PUT requests are rather invoked by using dedicated command line
options.
.Pp
This option only changes the actual word used in the HTTP request, it
does not alter the way curl behaves. So for example if you want to
make a proper HEAD request, using -X HEAD will not suffice. You need
to use the \fI-I, --head\fP option.
.Pp
The method string you set with \fI-X, --request\fP will be used for
all requests, which if you for example use \fI-L, --location\fP may
cause unintended side-effects when curl doesn't change request method
according to the HTTP 30x response codes - and similar.
.Pp
(FTP) Specifies a custom FTP command to use instead of LIST when doing
file lists with FTP.
.Pp
(POP3) Specifies a custom POP3 command to use instead of LIST or
RETR. (Added in 7.26.0)
.Pp
(IMAP) Specifies a custom IMAP command to use instead of LIST. (Added
in 7.30.0)
.Pp
(SMTP) Specifies a custom SMTP command to use instead of HELP or
VRFY. (Added in 7.34.0)
.Pp
If this option is used several times, the last one will be used.
.It Fl "--resolve <host:port:address[,address]...>"
Provide a custom address for a specific host and port pair. Using
this, you can make the curl requests(s) use a specified address and
prevent the otherwise normally resolved address to be used. Consider
it a sort of /etc/hosts alternative provided on the command line. The
port number should be the number used for the specific protocol the
host will be used for. It means you need several entries if you want
to provide address for the same host but different ports.
.Pp
By specifying '*' as host you can tell curl to resolve any host and
specific port pair to the specified address. Wildcard is resolved last
so any \fI--resolve\fP with a specific host and port will be used
first.
.Pp
The provided address set by this option will be used even if \fI-4,
--ipv4\fP or \fI-6, --ipv6\fP is set to make curl use another IP
version.
.Pp
Support for providing the IP address within [brackets] was added in 7.57.0.
.Pp
Support for providing multiple IP addresses per entry was added in 7.59.0.
.Pp
Support for resolving with wildcard was added in 7.64.0.
.Pp
This option can be used many times to add many host names to resolve.
.Pp
Added in 7.21.3.
.It Fl -retry-connrefused
In addition to the other conditions, consider ECONNREFUSED as a
transient error too for \fI--retry\fP. This option is used together
with --retry.
.Pp
Added in 7.52.0.
.It Fl -retry-delay Ar <seconds>
Make curl sleep this amount of time before each retry when a transfer
has failed with a transient error (it changes the default backoff time
algorithm between retries). This option is only interesting if
\fI--retry\fP is also used. Setting this delay to zero will make curl
use the default backoff time.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.12.3.
.It Fl -retry-max-time Ar <seconds>
The retry timer is reset before the first transfer attempt. Retries
will be done as usual (see \fI--retry\fP) as long as the timer hasn't
reached this given limit. Notice that if the timer hasn't reached the
limit, the request will be made and while performing, it may take
longer than this given time period. To limit a single request\'s
maximum time, use \fI-m, --max-time\fP.  Set this option to zero to
not timeout retries.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.12.3.
.It Fl -retry Ar <num>
If a transient error is returned when curl tries to perform a
transfer, it will retry this number of times before giving up. Setting
the number to 0 makes curl do no retries (which is the
default). Transient error means either: a timeout, an FTP 4xx response
code or an HTTP 408 or 5xx response code.
.Pp
When curl is about to retry a transfer, it will first wait one second
and then for all forthcoming retries it will double the waiting time
until it reaches 10 minutes which then will be the delay between the
rest of the retries.  By using \fI--retry-delay\fP you disable this
exponential backoff algorithm. See also \fI--retry-max-time\fP to
limit the total time allowed for retries.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.12.3.
.It Fl -sasl-ir
Enable initial response in SASL authentication.
.Pp
Added in 7.31.0.
.It Fl -service-name Ar <name>
This option allows you to change the service name for SPNEGO.
.Pp
Examples: \fI--negotiate\fP \fI--service-name\fP sockd would use
sockd/server-name.
.Pp
Added in 7.43.0.
.It Fl S | -show-error
When used with \fI-s, --silent\fP, it makes curl show an error message
if it fails.
.It Fl s | -silent
Silent or quiet mode. Don't show progress meter or error messages.
Makes Curl mute. It will still output the data you ask for,
potentially even to the terminal/stdout unless you redirect it.
.Pp
Use \fI-S, --show-error\fP in addition to this option to disable
progress meter but still show error messages.
.Pp
See also \fI-v, --verbose\fP and \fI--stderr\fP.
.It Fl -socks4 Ar <host[:port]>
Use the specified SOCKS4 proxy. If the port number is not specified,
it is assumed at port 1080.
.Pp
This option overrides any previous use of \fI-x, --proxy\fP, as they
are mutually exclusive.
.Pp
Since 7.21.7, this option is superfluous since you can specify a
socks4 proxy with \fI-x, --proxy\fP using a socks4:// protocol prefix.
.Pp
Since 7.52.0, \fI--preproxy\fP can be used to specify a SOCKS proxy at
the same time \fI-x, --proxy\fP is used with an HTTP/HTTPS proxy. In
such a case curl first connects to the SOCKS proxy and then connects
(through SOCKS) to the HTTP or HTTPS proxy.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.15.2.
.It Fl -socks4a Ar <host[:port]>
Use the specified SOCKS4a proxy. If the port number is not specified,
it is assumed at port 1080.
.Pp
This option overrides any previous use of \fI-x, --proxy\fP, as they
are mutually exclusive.
.Pp
Since 7.21.7, this option is superfluous since you can specify a
socks4a proxy with \fI-x, --proxy\fP using a socks4a:// protocol
prefix.
.Pp
Since 7.52.0, \fI--preproxy\fP can be used to specify a SOCKS proxy at
the same time \fI-x, --proxy\fP is used with an HTTP/HTTPS proxy. In
such a case curl first connects to the SOCKS proxy and then connects
(through SOCKS) to the HTTP or HTTPS proxy.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.18.0.
.It Fl -socks5-basic
Tells curl to use username/password authentication when connecting to
a SOCKS5 proxy.  The username/password authentication is enabled by
default.  Use \fI--socks5-gssapi\fP to force GSS-API authentication to
SOCKS5 proxies.
.Pp
Added in 7.55.0.
.It Fl -socks5-gssapi-nec
As part of the GSS-API negotiation a protection mode is
negotiated. RFC 1961 says in section 4.3/4.4 it should be protected,
but the NEC reference implementation does not.  The option
\fI--socks5-gssapi-nec\fP allows the unprotected exchange of the
protection mode negotiation.
.Pp
Added in 7.19.4.
.It Fl -socks5-gssapi-service Ar <name>
The default service name for a socks server is rcmd/server-fqdn. This
option allows you to change it.
.Pp
Examples: \fI--socks5\fP proxy-name \fI--socks5-gssapi-service\fP sockd would use
sockd/proxy-name \fI--socks5\fP proxy-name \fI--socks5-gssapi-service\fP sockd/real-name
would use sockd/real-name for cases where the proxy-name does not match the
principal name.
.Pp
Added in 7.19.4.
.It Fl -socks5-gssapi
Tells curl to use GSS-API authentication when connecting to a SOCKS5
proxy.  The GSS-API authentication is enabled by default (if curl is
compiled with GSS-API support).  Use \fI--socks5-basic\fP to force
username/password authentication to SOCKS5 proxies.
.Pp
Added in 7.55.0.
.It Fl -socks5-hostname Ar <host[:port]>
Use the specified SOCKS5 proxy (and let the proxy resolve the host
name). If the port number is not specified, it is assumed at port
1080.
.Pp
This option overrides any previous use of \fI-x, --proxy\fP, as they
are mutually exclusive.
.Pp
Since 7.21.7, this option is superfluous since you can specify a socks5
hostname proxy with \fI-x, --proxy\fP using a socks5h:// protocol prefix.
.Pp
Since 7.52.0, \fI--preproxy\fP can be used to specify a SOCKS proxy at
the same time \fI-x, --proxy\fP is used with an HTTP/HTTPS proxy. In
such a case curl first connects to the SOCKS proxy and then connects
(through SOCKS) to the HTTP or HTTPS proxy.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.18.0.
.It Fl -socks5 Ar <host[:port]>
Use the specified SOCKS5 proxy - but resolve the host name locally. If
the port number is not specified, it is assumed at port 1080.
.Pp
This option overrides any previous use of \fI-x, --proxy\fP, as they
are mutually exclusive.
.Pp
Since 7.21.7, this option is superfluous since you can specify a
socks5 proxy with \fI-x, --proxy\fP using a socks5:// protocol prefix.
.Pp
Since 7.52.0, \fI--preproxy\fP can be used to specify a SOCKS proxy at
the same time \fI-x, --proxy\fP is used with an HTTP/HTTPS proxy. In
such a case curl first connects to the SOCKS proxy and then connects
(through SOCKS) to the HTTP or HTTPS proxy.
.Pp
If this option is used several times, the last one will be used.
.Pp
This option (as well as \fI--socks4\fP) does not work with IPV6, FTPS
or LDAP.
.Pp
Added in 7.18.0.
.It Fl Y Ar speed | Fl -speed-limit Ar <speed>
If a download is slower than this given speed (in bytes per second)
for speed-time seconds it gets aborted. speed-time is set with \fI-y,
--speed-time\fP and is 30 if not set.
.Pp
If this option is used several times, the last one will be used.
.It Fl Fl y Ar seconds | -speed-time Ar <seconds>
If a download is slower than speed-limit bytes per second during a
speed-time period, the download gets aborted. If speed-time is used,
the default speed-limit will be 1 unless set with \fI-Y,
--speed-limit\fP.
.Pp
This option controls transfers and thus will not affect slow connects
etc. If this is a concern for you, try the \fI--connect-timeout\fP
option.
.Pp
If this option is used several times, the last one will be used.
.It Fl -ssl-allow-beast
This option tells curl to not work around a security flaw in the SSL3
and TLS1.0 protocols known as BEAST.  If this option isn't used, the
SSL layer may use workarounds known to cause interoperability problems
with some older SSL implementations. WARNING: this option loosens the
SSL security, and by using this flag you ask for exactly that.
.Pp
Added in 7.25.0.
.It Fl -ssl-no-revoke
(Schannel) This option tells curl to disable certificate revocation
checks.  WARNING: this option loosens the SSL security, and by using
this flag you ask for exactly that.
.Pp
Added in 7.44.0.
.It Fl -ssl-reqd
(FTP IMAP POP3 SMTP) Require SSL/TLS for the connection.  Terminates
the connection if the server doesn't support SSL/TLS.
.Pp
This option was formerly known as --ftp-ssl-reqd.
.Pp
Added in 7.20.0.
.It Fl -ssl
(FTP IMAP POP3 SMTP) Try to use SSL/TLS for the connection.  Reverts
to a non-secure connection if the server doesn't support SSL/TLS.  See
also \fI--ftp-ssl-control\fP and \fI--ssl-reqd\fP for different levels
of encryption required.
.Pp
This option was formerly known as --ftp-ssl (Added in 7.11.0). That
option name can still be used but will be removed in a future version.
.Pp
Added in 7.20.0.
.It Fl 2 | -sslv2
(SSL) Forces curl to use SSL version 2 when negotiating with a remote
SSL server. Sometimes curl is built without SSLv2 support. SSLv2 is
widely considered insecure (see RFC 6176).
.Pp
See also \fI--http1.1\fP and \fI--http2\fP. \fI-2, --sslv2\fP requires
that the underlying libgnurl was built to support TLS. This option
overrides \fI-3, --sslv3\fP and \fI-1, --tlsv1\fP and \fI--tlsv1.1\fP
and \fI--tlsv1.2\fP.
.It Fl 3 | -sslv3
(SSL) Forces curl to use SSL version 3 when negotiating with a remote
SSL server. Sometimes curl is built without SSLv3 support. SSLv3 is
widely considered insecure (see RFC 7568).
.Pp
See also \fI--http1.1\fP and \fI--http2\fP. \fI-3, --sslv3\fP requires
that the underlying libgnurl was built to support TLS. This option
overrides \fI-2, --sslv2\fP and \fI-1, --tlsv1\fP and \fI--tlsv1.1\fP
and \fI--tlsv1.2\fP.
.It Fl -stderr
Redirect all writes to stderr to the specified file instead. If the
file name is a plain '-', it is instead written to stdout.
.Pp
If this option is used several times, the last one will be used.
.Pp
See also \fI-v, --verbose\fP and \fI-s, --silent\fP.
.It Fl -styled-output
Enables the automatic use of bold font styles when writing HTTP
headers to the terminal. Use --no-styled-output to switch them off.
.Pp
Added in 7.61.0.
.It Fl -suppress-connect-headers
When \fI-p, --proxytunnel\fP is used and a CONNECT request is made
don't output proxy CONNECT response headers. This option is meant to
be used with \fI-D, --dump-header\fP or \fI-i, --include\fP which are
used to show protocol headers in the output. It has no effect on debug
options such as \fI-v, --verbose\fP or \fI--trace\fP, or any
statistics.
.Pp
See also \fI-D, --dump-header\fP and \fI-i, --include\fP and \fI-p,
--proxytunnel\fP.
.It Fl -tcp-fastopen
Enable use of TCP Fast Open (RFC7413).
.Pp
Added in 7.49.0.
.It Fl -tcp-nodelay
Turn on the TCP_NODELAY option. See the \fIcurl_easy_setopt(3)\fP man
page for details about this option.
.Pp
Since 7.50.2, curl sets this option by default and you need to
explicitly switch it off if you don't want it on.
.Pp
Added in 7.11.2.
.It Fl t Ar opt=val | Fl -telnet-option Ar <opt=val>
Pass options to the telnet protocol. Supported options are:
.Bl -tag -width indent
.It TTYPE=<term>
Sets the terminal type.
.It XDISPLOC=<X display>
Sets the X display location.
.It NEW_ENV=<var,val>
Sets an environment variable.
.It Fl -tftp-blksize Ar <value>
(TFTP) Set TFTP BLKSIZE option (must be >512). This is the block size
that curl will try to use when transferring data to or from a TFTP
server. By default 512 bytes will be used.
.Pp
If this option is used several times, the last one will be used.
.Pp
Added in 7.20.0.
.It Fl -tftp-no-options
(TFTP) Tells curl not to send TFTP options requests.
.Pp
This option improves interop with some legacy servers that do not
acknowledge or properly implement TFTP options. When this option is
used \fI--tftp-blksize\fP is ignored.
.Pp
Added in 7.48.0.
.It Fl z time | -time-cond Ar <time>
(HTTP FTP) Request a file that has been modified later than the given
time and date, or one that has been modified before that time. The
<date expression> can be all sorts of date strings or if it doesn't
match any internal ones, it is taken as a filename and tries to get
the modification date (mtime) from <file> instead. See the
\fIcurl_getdate(3)\fP man pages for date expression details.
.Pp
Start the date expression with a dash (-) to make it request for a
document that is older than the given date/time, default is a document
that is newer than the specified date/time.
.Pp
If this option is used several times, the last one will be used.
.It Fl -tls-max Ar <VERSION>
(SSL) VERSION defines maximum supported TLS version. The minimum
acceptable version is set by tlsv1.0, tlsv1.1, tlsv1.2 or tlsv1.3.
.Bl -tag -width indent
.It default
Use up to recommended TLS version.
.It 1.0
Use up to TLSv1.0.
.It 1.1
Use up to TLSv1.1.
.It 1.2
Use up to TLSv1.2.
.It 1.3
Use up to TLSv1.3.
.El
See also \fI--tlsv1.0\fP and \fI--tlsv1.1\fP and \fI--tlsv1.2\fP and
\fI--tlsv1.3\fP. \fI--tls-max\fP requires that the underlying libgnurl
was built to support TLS. Added in 7.54.0.
.It Fl -tls13-ciphers Ar <list of TLS 1.3 ciphersuites>
(TLS) Specifies which cipher suites to use in the connection if it
negotiates TLS 1.3. The list of ciphers suites must specify valid
ciphers. Read up on TLS 1.3 cipher suite details on this URL:
.Lk https://curl.haxx.se/docs/ssl-ciphers.html
.Pp
If this option is used several times, the last one will be used.
.It Fl -tlsauthtype Ar <type>
Set TLS authentication type. Currently, the only supported option is
"SRP", for TLS-SRP (RFC 5054). If \fI--tlsuser\fP and
\fI--tlspassword\fP are specified but \fI--tlsauthtype\fP is not, then
this option defaults to "SRP".  This option works only if the
underlying libcurl is built with TLS-SRP support, which requires
OpenSSL or GnuTLS with TLS-SRP support.
.Pp
Added in 7.21.4.
.It Fl -tlspassword
Set password for use with the TLS authentication method specified with
\fI--tlsauthtype\fP. Requires that \fI--tlsuser\fP also be set.
.Pp
Added in 7.21.4.
.It Fl -tlsuser Ar <name>
Set username for use with the TLS authentication method specified with
\fI--tlsauthtype\fP. Requires that \fI--tlspassword\fP also is set.
.Pp
Added in 7.21.4.
.It Fl -tlsv1.0
(TLS) Forces curl to use TLS version 1.0 or later when connecting to a remote TLS server.

Added in 7.34.0.
.It Fl -tlsv1.1
(TLS) Forces curl to use TLS version 1.1 or later when connecting to a remote TLS server.

Added in 7.34.0.
.It Fl -tlsv1.2
(TLS) Forces curl to use TLS version 1.2 or later when connecting to a remote TLS server.

Added in 7.34.0.
.It Fl -tlsv1.3
(TLS) Forces curl to use TLS version 1.3 or later when connecting to a remote TLS server.

Note that TLS 1.3 is only supported by a subset of TLS backends. At the time
of this writing, they are BoringSSL, NSS, and Secure Transport (on iOS 11 or
later, and macOS 10.13 or later).

Added in 7.52.0.
.It Fl 1 | -tlsv1
(SSL) Tells curl to use at least TLS version 1.x when negotiating with a remote TLS
server. That means TLS version 1.0 or higher

See also \fI--http1.1\fP and \fI--http2\fP. \fI-1, --tlsv1\fP requires
that the underlying libgnurl was built to support TLS. This option
overrides \fI--tlsv1.1\fP and \fI--tlsv1.2\fP and \fI--tlsv1.3\fP.
.It Fl -tr-encoding
(HTTP) Request a compressed Transfer-Encoding response using one of the algorithms
curl supports, and uncompress the data while receiving it.

Added in 7.21.6.
.It Fl -trace-ascii Ar <file>
Enables a full trace dump of all incoming and outgoing data, including
descriptive information, to the given output file. Use "-" as filename to have
the output sent to stdout.

This is very similar to \fI--trace\fP, but leaves out the hex part and only shows
the ASCII part of the dump. It makes smaller output that might be easier to
read for untrained humans.

If this option is used several times, the last one will be used.

This option overrides \fI--trace\fP and \fI-v, --verbose\fP.
.It Fl -trace-time
Prepends a time stamp to each trace or verbose line that curl displays.

Added in 7.14.0.
.It Fl -trace Ar <file>
Enables a full trace dump of all incoming and outgoing data, including
descriptive information, to the given output file. Use "-" as filename to have
the output sent to stdout. Use "%" as filename to have the output sent to
stderr.

If this option is used several times, the last one will be used.

This option overrides \fI-v, --verbose\fP and \fI--trace-ascii\fP.
.It Fl -unix-socket Ar <path>
(HTTP) Connect through this Unix domain socket, instead of using the network.

Added in 7.40.0.
.It Fl T Ar file | Fl -upload-file Ar <file>
This transfers the specified local file to the remote URL. If there is
no file part in the specified URL, curl will append the local file
name. NOTE that you must use a trailing / on the last directory to
really prove to Curl that there is no file name or curl will think
that your last directory name is the remote file name to use. That
will most likely cause the upload operation to fail. If this is used
on an HTTP(S) server, the PUT command will be used.
.Pp
Use the file name "-" (a single dash) to use stdin instead of a given
file.  Alternately, the file name "." (a single period) may be
specified instead of "-" to use stdin in non-blocking mode to allow
reading server output while stdin is being uploaded.
.Pp
You can specify one \fI-T, --upload-file\fP for each URL on the
command line. Each \fI-T, --upload-file\fP + URL pair specifies what
to upload and to where. curl also supports "globbing" of the \fI-T,
--upload-file\fP argument, meaning that you can upload multiple files
to a single URL by using the same URL globbing style supported in the
URL, like this:
.Pp
.Dl curl --upload-file "{file1,file2}" http://www.example.com
.Pp
or even
.Pp
.Dl curl -T "img[1-1000].png" ftp://ftp.example.com/upload/
.Pp
When uploading to an SMTP server: the uploaded data is assumed to be
RFC 5322 formatted. It has to feature the necessary set of headers and
mail body formatted correctly by the user as curl will not transcode
nor encode it further in any way.
.It Fl -url Ar <url>
Specify a URL to fetch. This option is mostly handy when you want to
specify URL(s) in a config file.
.Pp
If the given URL is missing a scheme name (such as "http://" or
"ftp://" etc) then curl will make a guess based on the host. If the
outermost sub-domain name matches DICT, FTP, IMAP, LDAP, POP3 or SMTP
then that protocol will be used, otherwise HTTP will be used. Since
7.45.0 guessing can be disabled by setting a default protocol, see
\fI--proto-default\fP for details.
.Pp
This option may be used any number of times. To control where this URL
is written, use the \fI-o, --output\fP or the \fI-O, --remote-name\fP
options.
.It Fl B | -use-ascii
(FTP LDAP) Enable ASCII transfer. For FTP, this can also be enforced
by using a URL that ends with ";type=A". This option causes data sent
to stdout to be in text mode for win32 systems.
.It Fl A Ar <name> | Fl -user-agent Ar <name>
(HTTP)
Specify the User-Agent string to send to the HTTP server. To encode blanks in
the string, surround the string with single quote marks. This header can also
be set with the \fI-H, --header\fP or the \fI--proxy-header\fP options.
.Pp
If this option is used several times, the last one will be used.
.It Fl u Ar <user:password> | Fl -user Ar <user:password>
Specify the user name and password to use for server authentication. Overrides
\fI-n, --netrc\fP and \fI--netrc-optional\fP.
.Pp
If you simply specify the user name, curl will prompt for a password.
.Pp
The user name and passwords are split up on the first colon, which makes it
impossible to use a colon in the user name with this option. The password can,
still.
.Pp
On systems where it works, curl will hide the given option argument from
process listings. This is not enough to protect credentials from possibly
getting seen by other users on the same system as they will still be visible
for a brief moment before cleared. Such sensitive data should be retrieved
from a file instead or similar and never used in clear text in a command line.
.Pp
When using Kerberos V5 with a Windows based server you should include the
Windows domain name in the user name, in order for the server to successfully
obtain a Kerberos Ticket. If you don't then the initial authentication
handshake may fail.
.Pp
When using NTLM, the user name can be specified simply as the user name,
without the domain, if there is a single domain and forest in your setup
for example.
.Pp
To specify the domain name use either Down-Level Logon Name or UPN (User
Principal Name) formats. For example, EXAMPLE\\user and user@example.com
respectively.
.Pp
If you use a Windows SSPI-enabled curl binary and perform Kerberos V5,
Negotiate, NTLM or Digest authentication then you can tell curl to select
the user name and password from your environment by specifying a single colon
with this option: "-u :".
.Pp
If this option is used several times, the last one will be used.
.It Fl v | -verbose
Makes curl verbose during the operation. Useful for debugging and seeing
what's going on "under the hood". A line starting with '>' means "header data"
sent by curl, '<' means "header data" received by curl that is hidden in
normal cases, and a line starting with '*' means additional info provided by
curl.
.Pp
If you only want HTTP headers in the output,
.Fl i | -include
might be the option you're looking for.
.Pp
If you think this option still doesn't give you enough details, consider using
.Fl -trace
or
.Fl -trace-ascii
instead.
.Pp
Use
.Fl s | -silent
to make curl really quiet.
.Pp
See also
.Fl i | -include .
This option overrides
.Fl -trace
and
.Fl -trace-ascii .
.It Fl V | -version
Displays information about curl and the libcurl version it uses.
.Pp
The first line includes the full version of curl, libcurl and other 3rd party
libraries linked with the executable.
.Pp
The second line (starts with "Protocols:") shows all protocols that libcurl
reports to support.
.Pp
The third line (starts with "Features:") shows specific features libcurl
reports to offer. Available features include:
.Bl -tag -width indent
.It IPv6
You can use IPv6 with this.
.It krb4
Krb4 for FTP is supported.
.It SSL
SSL versions of various protocols are supported, such as HTTPS, FTPS, POP3S
and so on.
.It libz
Automatic decompression of compressed files over HTTP is supported.
.It NTLM
NTLM authentication is supported.
.It Debug
This curl uses a libcurl built with Debug. This enables more error-tracking
and memory debugging etc. For curl-developers only!
.It AsynchDNS
This curl uses asynchronous name resolves. Asynchronous name resolves can be
done using either the c-ares or the threaded resolver backends.
.It SPNEGO
SPNEGO authentication is supported.
.It Largefile
This curl supports transfers of large files, files larger than 2GB.
.It IDN
This curl supports IDN - international domain names.
.It GSS-API
GSS-API is supported.
.It SSPI
SSPI is supported.
.It TLS-SRP
SRP (Secure Remote Password) authentication is supported for TLS.
.It HTTP2
HTTP/2 support has been built-in.
.It UnixSockets
Unix sockets support is provided.
.It HTTPS-proxy
This curl is built to support HTTPS proxy.
.It Metalink
This curl supports Metalink (both version 3 and 4 (RFC 5854)), which
describes mirrors and hashes.  curl will use mirrors for failover if
there are errors (such as the file or server not being available).
.It PSL
PSL is short for Public Suffix List and means that this curl has been built
with knowledge about "public suffixes".
.It MultiSSL
This gnurl supports multiple TLS backends.
.El
.It Fl w  Ar <format> | Fl -write-out Ar <format>
Make curl display information on stdout after a completed transfer. The format
is a string that may contain plain text mixed with any number of
variables. The format can be specified as a literal "string", or you can have
curl read the format from a file with "@filename" and to tell curl to read the
format from stdin you write "@-".
.Pp
The variables present in the output format will be substituted by the value or
text that curl thinks fit, as described below. All variables are specified as
%{variable_name} and to output a normal % you just write them as %%. You can
output a newline by using \\n, a carriage return with \\r and a tab space with
\\t.
.Pp
The output will be written to standard output, but this can be switched to
standard error by using %{stderr}.
.Pp
.B NOTE:
The %-symbol is a special symbol in the win32-environment, where all
occurrences of % must be doubled when using this option.

The variables available are:
.RS
.TP 15
.B content_type
The Content-Type of the requested document, if there was any.
.TP
.B filename_effective
The ultimate filename that curl writes out to. This is only meaningful if curl
is told to write to a file with the \fI-O, --remote-name\fP or \fI-o, --output\fP
option. It's most useful in combination with the \fI-J, --remote-header-name\fP
option. (Added in 7.26.0)
.TP
.B ftp_entry_path
The initial path curl ended up in when logging on to the remote FTP
server. (Added in 7.15.4)
.TP
.B http_code
The numerical response code that was found in the last retrieved HTTP(S) or
FTP(s) transfer. In 7.18.2 the alias \fBresponse_code\fP was added to show the
same info.
.TP
.B http_connect
The numerical code that was found in the last response (from a proxy) to a
curl CONNECT request. (Added in 7.12.4)
.TP
.B http_version
The http version that was effectively used. (Added in 7.50.0)
.TP
.B local_ip
The IP address of the local end of the most recently done connection - can be
either IPv4 or IPv6 (Added in 7.29.0)
.TP
.B local_port
The local port number of the most recently done connection (Added in 7.29.0)
.TP
.B num_connects
Number of new connects made in the recent transfer. (Added in 7.12.3)
.TP
.B num_redirects
Number of redirects that were followed in the request. (Added in 7.12.3)
.TP
.B proxy_ssl_verify_result
The result of the HTTPS proxy's SSL peer certificate verification that was
requested. 0 means the verification was successful. (Added in 7.52.0)
.TP
.B redirect_url
When an HTTP request was made without \fI-L, --location\fP to follow redirects (or when
--max-redir is met), this variable will show the actual URL a redirect
\fIwould\fP have gone to. (Added in 7.18.2)
.TP
.B remote_ip
The remote IP address of the most recently done connection - can be either
IPv4 or IPv6 (Added in 7.29.0)
.TP
.B remote_port
The remote port number of the most recently done connection (Added in 7.29.0)
.TP
.B scheme
The URL scheme (sometimes called protocol) that was effectively used (Added in 7.52.0)
.TP
.B size_download
The total amount of bytes that were downloaded.
.TP
.B size_header
The total amount of bytes of the downloaded headers.
.TP
.B size_request
The total amount of bytes that were sent in the HTTP request.
.TP
.B size_upload
The total amount of bytes that were uploaded.
.TP
.B speed_download
The average download speed that curl measured for the complete download. Bytes
per second.
.TP
.B speed_upload
The average upload speed that curl measured for the complete upload. Bytes per
second.
.TP
.B ssl_verify_result
The result of the SSL peer certificate verification that was requested. 0
means the verification was successful. (Added in 7.19.0)
.TP
.B stderr
From this point on, the \fI-w, --write-out\fP output will be written to standard
error. (Added in 7.63.0)
.TP
.B stdout
From this point on, the \fI-w, --write-out\fP output will be written to standard output.
This is the default, but can be used to switch back after switching to stderr.
(Added in 7.63.0)
.TP
.B time_appconnect
The time, in seconds, it took from the start until the SSL/SSH/etc
connect/handshake to the remote host was completed. (Added in 7.19.0)
.TP
.B time_connect
The time, in seconds, it took from the start until the TCP connect to the
remote host (or proxy) was completed.
.TP
.B time_namelookup
The time, in seconds, it took from the start until the name resolving was
completed.
.TP
.B time_pretransfer
The time, in seconds, it took from the start until the file transfer was just
about to begin. This includes all pre-transfer commands and negotiations that
are specific to the particular protocol(s) involved.
.TP
.B time_redirect
The time, in seconds, it took for all redirection steps including name lookup,
connect, pretransfer and transfer before the final transaction was
started. time_redirect shows the complete execution time for multiple
redirections. (Added in 7.12.3)
.TP
.B time_starttransfer
The time, in seconds, it took from the start until the first byte was just
about to be transferred. This includes time_pretransfer and also the time the
server needed to calculate the result.
.TP
.B time_total
The total time, in seconds, that the full operation lasted.
.TP
.B url_effective
The URL that was fetched last. This is most meaningful if you've told curl
to follow location: headers.
.RE
.It Fl
If this option is used several times, the last one will be used.
.It Fl -xattr
When saving output to a file, this option tells curl to store certain file
metadata in extended file attributes. Currently, the URL is stored in the
xdg.origin.url attribute and, for HTTP, the content type is stored in
the mime_type attribute. If the file system does not support extended
attributes, a warning is issued.
.El
.Sh FILES
.Pa ~/.curlrc
default config file, see
.Fl -config
for details.
.Sh ENVIRONMENT
The environment variables can be specified in lower case or upper case. The
lower case version has precedence. http_proxy is an exception as it is only
available in lower case.
.Pp
Using an environment variable to set the proxy has the same effect as using
the
.Fl -proxy
option.
.Pp
.IP "http_proxy [protocol://]<host>[:port]"
Sets the proxy server to use for HTTP.
.IP "HTTPS_PROXY [protocol://]<host>[:port]"
Sets the proxy server to use for HTTPS.
.IP "[url-protocol]_PROXY [protocol://]<host>[:port]"
Sets the proxy server to use for [url-protocol], where the protocol is a
protocol that curl supports and as specified in a URL. FTP, FTPS, POP3, IMAP,
SMTP, LDAP etc.
.IP "ALL_PROXY [protocol://]<host>[:port]"
Sets the proxy server to use if no protocol-specific proxy is set.
.IP "NO_PROXY <comma-separated list of hosts/domains>"
list of host names that shouldn't go through any proxy. If set to an asterisk
\&'*' only, it matches all hosts. Each name in this list is matched as either
a domain name which contains the hostname, or the hostname itself.

This environment variable disables use of the proxy even when specified with
the \fI-x, --proxy\fP option. That is
.B NO_PROXY=direct.example.com curl -x http://proxy.example.com
.B http://direct.example.com
accesses the target URL directly, and
.B NO_PROXY=direct.example.com curl -x http://proxy.example.com
.B http://somewhere.example.com
accesses the target URL through the proxy.
.Pp
The list of host names can also be include numerical IP addresses, and IPv6
versions should then be given without enclosing brackets.
.Pp
.Sh PROXY PROTOCOL PREFIXES
Since curl version 7.21.7, the proxy string may be specified with a
protocol:// prefix to specify alternative proxy protocols.
.Pp
If no protocol is specified in the proxy string or if the string doesn't match
a supported one, the proxy will be treated as an HTTP proxy.
.Pp
The supported proxy protocol prefixes are as follows:
.Bl -tag -width indent
.It http://
Makes it use it as an HTTP proxy.
The default if no scheme prefix is used.
.It https://
Makes it treated as an \fBHTTPS\fP proxy.
.It socks4://
Makes it the equivalent of
.Fl -socks4
.It socks4a://
Makes it the equivalent of
.Fl -socks4a
.It socks5://
Makes it the equivalent of
.Fl -socks5
.It socks5h://
Makes it the equivalent of
.Fl -socks5-hostname
.El
.Sh EXIT STATUS
There are a bunch of different error codes and their corresponding error
messages that may appear during bad conditions. At the time of this writing,
the exit codes are:
.Bl -tag -width indent
.It 1
Unsupported protocol. This build of curl has no support for this protocol.
.It 2
Failed to initialize.
.It 3
URL malformed. The syntax was not correct.
.It 4
A feature or option that was needed to perform the desired request was not
enabled or was explicitly disabled at build-time. To make curl able to do
this, you probably need another build of libcurl!
.It 5
Couldn't resolve proxy. The given proxy host could not be resolved.
.It 6
Couldn't resolve host. The given remote host was not resolved.
.It 7
Failed to connect to host.
.It 8
Weird server reply. The server sent data curl couldn't parse.
.It 9
FTP access denied. The server denied login or denied access to the
particular resource or directory you wanted to reach. Most often you
tried to change to a directory that doesn't exist on the server.
.It 10
FTP accept failed. While waiting for the server to connect back when
an active FTP session is used, an error code was sent over the control
connection or similar.
.It 11
FTP weird PASS reply. Curl couldn't parse the reply sent to the PASS
request.
.It 12
During an active FTP session while waiting for the server to connect
back to curl, the timeout expired.
.It 13
FTP weird PASV reply, Curl couldn't parse the reply sent to the PASV
request.
.It 14
FTP weird 227 format. Curl couldn't parse the 227-line the server sent.
.It 15
FTP can't get host. Couldn't resolve the host IP we got in the 227-line.
.It 16
HTTP/2 error. A problem was detected in the HTTP2 framing layer. This
is somewhat generic and can be one out of several problems, see the
error message for details.
.It 17
FTP couldn't set binary. Couldn't change transfer method to binary.
.It 18
Partial file. Only a part of the file was transferred.
.It 19
FTP couldn't download/access the given file, the RETR (or similar) command
failed.
.It 21
FTP quote error. A quote command returned error from the server.
.It 22
HTTP page not retrieved. The requested url was not found or returned
another error with the HTTP error code being 400 or above. This return
code only appears if
.Fl f | -fail
is used.
.It 23
Write error. Curl couldn't write data to a local filesystem or similar.
.It 25
FTP couldn't STOR file. The server denied the STOR operation, used for
FTP uploading.
.It 26
Read error. Various reading problems.
.It 27
Out of memory. A memory allocation request failed.
.It 28
Operation timeout. The specified time-out period was reached according
to the conditions.
.It 30
FTP PORT failed. The PORT command failed. Not all FTP servers support
the PORT command, try doing a transfer using PASV instead!
.It 31
FTP couldn't use REST. The REST command failed. This command is used
for resumed FTP transfers.
.It 33
HTTP range error. The range "command" didn't work.
.It 34
HTTP post error. Internal post-request generation error.
.It 35
SSL connect error. The SSL handshaking failed.
.It 36
Bad download resume. Couldn't continue an earlier aborted download.
.It 37
FILE couldn't read file. Failed to open the file. Permissions?
.It 38
LDAP cannot bind. LDAP bind operation failed.
.It 39
LDAP search failed.
.It 41
Function not found. A required LDAP function was not found.
.It 42
Aborted by callback. An application told curl to abort the operation.
.It 43
Internal error. A function was called with a bad parameter.
.It 45
Interface error. A specified outgoing interface could not be used.
.It 47
Too many redirects. When following redirects, curl hit the maximum amount.
.It 48
Unknown option specified to libcurl. This indicates that you passed a
weird option to curl that was passed on to libcurl and rejected. Read
up in the manual!
.It 49
Malformed telnet option.
.It 51
The peer's SSL certificate or SSH MD5 fingerprint was not OK.
.It 52
The server didn't reply anything, which here is considered an error.
.It 53
SSL crypto engine not found.
.It 54
Cannot set SSL crypto engine as default.
.It 55
Failed sending network data.
.It 56
Failure in receiving network data.
.It 58
Problem with the local certificate.
.It 59
Couldn't use specified SSL cipher.
.It 60
Peer certificate cannot be authenticated with known CA certificates.
.It 61
Unrecognized transfer encoding.
.It 62
Invalid LDAP URL.
.It 63
Maximum file size exceeded.
.It 64
Requested FTP SSL level failed.
.It 65
Sending the data requires a rewind that failed.
.It 66
Failed to initialise SSL Engine.
.It 67
The user name, password, or similar was not accepted and curl failed
to log in.
.It 68
File not found on TFTP server.
.It 69
Permission problem on TFTP server.
.It 70
Out of disk space on TFTP server.
.It 71
Illegal TFTP operation.
.It 72
Unknown TFTP transfer ID.
.It 73
File already exists (TFTP).
.It 74
No such user (TFTP).
.It 75
Character conversion failed.
.It 76
Character conversion functions required.
.It 77
Problem with reading the SSL CA cert (path? access rights?).
.It 78
The resource referenced in the URL does not exist.
.It 79
An unspecified error occurred during the SSH session.
.It 80
Failed to shut down the SSL connection.
.It 82
Could not load CRL file, missing or wrong format (added in 7.19.0).
.It 83
Issuer check failed (added in 7.19.0).
.It 84
The FTP PRET command failed
.It 85
RTSP: mismatch of CSeq numbers
.It 86
RTSP: mismatch of Session Identifiers
.It 87
unable to parse FTP file list
.It 88
FTP chunk callback reported error
.It 89
No connection available, the session will be queued
.It 90
SSL public key does not matched pinned public key
.It 91
Invalid SSL certificate status.
.It 92
Stream error in HTTP/2 framing layer.
.It XX
.El
More error codes will appear here in future releases. The existing
ones are meant to never change.
.Sh AUTHORS
Daniel Stenberg is the main author of curl, but the whole list of
contributors is found in the separate THANKS file.
.Pp
gnurl is based on curl and is maintained by
.An ng0 Aq Mt ng0@n0.is .
This mdoc man page was derived from the curl automated groff page
generation output and is slowly being adjusted to reflect the smaller
feature set found in gnurl.
.Sh SEE ALSO
.Lk https://curl.haxx.se ,
.Xr ftp 1 ,
.Xr wget 1