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Diffstat (limited to 'docs/libcurl/opts/GNURLOPT_CHUNK_BGN_FUNCTION.3')
| -rw-r--r-- | docs/libcurl/opts/GNURLOPT_CHUNK_BGN_FUNCTION.3 | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/docs/libcurl/opts/GNURLOPT_CHUNK_BGN_FUNCTION.3 b/docs/libcurl/opts/GNURLOPT_CHUNK_BGN_FUNCTION.3 new file mode 100644 index 000000000..a4ca84936 --- /dev/null +++ b/docs/libcurl/opts/GNURLOPT_CHUNK_BGN_FUNCTION.3 @@ -0,0 +1,141 @@ +.\" ************************************************************************** +.\" * _ _ ____ _ +.\" * Project ___| | | | _ \| | +.\" * / __| | | | |_) | | +.\" * | (__| |_| | _ <| |___ +.\" * \___|\___/|_| \_\_____| +.\" * +.\" * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al. +.\" * +.\" * This software is licensed as described in the file COPYING, which +.\" * you should have received as part of this distribution. The terms +.\" * are also available at https://curl.haxx.se/docs/copyright.html. +.\" * +.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell +.\" * copies of the Software, and permit persons to whom the Software is +.\" * furnished to do so, under the terms of the COPYING file. +.\" * +.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY +.\" * KIND, either express or implied. +.\" * +.\" ************************************************************************** +.\" +.TH GNURLOPT_CHUNK_BGN_FUNCTION 3 "19 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" +.SH NAME +CURLOPT_CHUNK_BGN_FUNCTION \- callback before a transfer with FTP wildcardmatch +.SH SYNOPSIS +.nf +#include <gnurl/curl.h> + +struct curl_fileinfo { + char *filename; + curlfiletype filetype; + time_t time; /* always zero! */ + unsigned int perm; + int uid; + int gid; + curl_off_t size; + long int hardlinks; + + struct { + /* If some of these fields is not NULL, it is a pointer to b_data. */ + char *time; + char *perm; + char *user; + char *group; + char *target; /* pointer to the target filename of a symlink */ + } strings; + + unsigned int flags; + + /* used internally */ + char *b_data; + size_t b_size; + size_t b_used; +}; + +long chunk_bgn_callback(const void *transfer_info, void *ptr, + int remains); + +CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CHUNK_BGN_FUNCTION, + chunk_bgn_callback); +.SH DESCRIPTION +Pass a pointer to your callback function, which should match the prototype +shown above. + +This callback function gets called by libcurl before a part of the stream is +going to be transferred (if the transfer supports chunks). + +The \fItransfer_info\fP pointer will point to a struct curl_fileinfo with +details about the file that is about to get transferred. + +This callback makes sense only when using the \fICURLOPT_WILDCARDMATCH(3)\fP +option for now. + +The target of transfer_info parameter is a "feature depended" structure. For +the FTP wildcard download, the target is curl_fileinfo structure (see +\fIgnurl/curl.h\fP). The parameter \fIptr\fP is a pointer given by +\fICURLOPT_CHUNK_DATA(3)\fP. The parameter remains contains number of chunks +remaining per the transfer. If the feature is not available, the parameter has +zero value. + +Return \fICURL_CHUNK_BGN_FUNC_OK\fP if everything is fine, +\fICURL_CHUNK_BGN_FUNC_SKIP\fP if you want to skip the concrete chunk or +\fICURL_CHUNK_BGN_FUNC_FAIL\fP to tell libcurl to stop if some error occurred. +.SH DEFAULT +NULL +.SH PROTOCOLS +FTP +.SH EXAMPLE +.nf +static long file_is_coming(struct curl_fileinfo *finfo, + struct callback_data *data, + int remains) +{ + printf("%3d %40s %10luB ", remains, finfo->filename, + (unsigned long)finfo->size); + + switch(finfo->filetype) { + case CURLFILETYPE_DIRECTORY: + printf(" DIR\\n"); + break; + case CURLFILETYPE_FILE: + printf("FILE "); + break; + default: + printf("OTHER\\n"); + break; + } + + if(finfo->filetype == CURLFILETYPE_FILE) { + /* do not transfer files >= 50B */ + if(finfo->size > 50) { + printf("SKIPPED\\n"); + return CURL_CHUNK_BGN_FUNC_SKIP; + } + + data->output = fopen(finfo->filename, "wb"); + if(!data->output) { + return CURL_CHUNK_BGN_FUNC_FAIL; + } + } + + return CURL_CHUNK_BGN_FUNC_OK; +} + +int main() +{ + /* data for callback */ + struct callback_data callback_info; + + /* callback is called before download of concrete file started */ + curl_easy_setopt(curl, CURLOPT_CHUNK_BGN_FUNCTION, file_is_coming); + curl_easy_setopt(curl, CURLOPT_CHUNK_DATA, &callback_info); +} +.fi +.SH AVAILABILITY +This was added in 7.21.0 +.SH RETURN VALUE +Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. +.SH "SEE ALSO" +.BR CURLOPT_CHUNK_END_FUNCTION "(3), " CURLOPT_WILDCARDMATCH "(3), " |