Loading docs/libcurl/opts/CURLOPT_HEADERFUNCTION.3 0 → 100644 +89 −0 Original line number Diff line number Diff line .\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2014, 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 http://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 CURLOPT_HEADERFUNCTION 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" .SH NAME CURLOPT_HEADERFUNCTION \- callback that receives header data .SH SYNOPSIS #include <curl/curl.h> size_t header_callback(char *buffer, size_t size, size_t nitems, void *userdata); CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HEADERFUNCTION, header_callback); .SH DESCRIPTION Pass a pointer to your callback function, which should match the prototype shown above. This function gets called by libcurl as soon as it has received header data. The header callback will be called once for each header and only complete header lines are passed on to the callback. Parsing headers is very easy using this. The size of the data pointed to by \fIptr\fP is \fIsize\fP multiplied with \fInmemb\fP. Do not assume that the header line is zero terminated! The pointer named \fIuserdata\fP is the one you set with the \fICURLOPT_HEADERDATA(3)\fP option. This callback function must return the number of bytes actually taken care of. If that amount differs from the amount passed in to your function, it'll signal an error to the library. This will cause the transfer to get aborted and the libcurl function in progress will return \fICURL_WRITE_ERROR\fP. A complete HTTP header that is passed to this function can be up to \fICURL_MAX_HTTP_HEADER\fP (100K) bytes. If this option is not set, or if it is set to NULL, but \fICURLOPT_HEADERDATA(3)\fP is set to anything but NULL, the function used to accept response data will be used instead. That is, it will be the function specified with \fICURLOPT_WRITEFUNCTION(3)\fP, or if it is not specified or NULL - the default, stream-writing function. It's important to note that the callback will be invoked for the headers of all responses received after initiating a request and not just the final response. This includes all responses which occur during authentication negotiation. If you need to operate on only the headers from the final response, you will need to collect headers in the callback yourself and use HTTP status lines, for example, to delimit response boundaries. When a server sends a chunked encoded transfer, it may contain a trailer. That trailer is identical to a HTTP header and if such a trailer is received it is passed to the application using this callback as well. There are several ways to detect it being a trailer and not an ordinary header: 1) it comes after the response-body. 2) it comes after the final header line (CR LF) 3) a Trailer: header among the regular response-headers mention what header(s) to expect in the trailer. For non-HTTP protocols like FTP, POP3, IMAP and SMTP this function will get called with the server responses to the commands that libcurl sends. .SH DEFAULT Nothing. .SH PROTOCOLS Used for all protocols with headers or meta-data concept: HTTP, FTP, POP3, IMAP, SMTP and more. .SH EXAMPLE TODO .SH AVAILABILITY Always .SH RETURN VALUE Returns CURLE_OK .SH "SEE ALSO" .BR CURLOPT_HEADERDATA "(3), " CURLOPT_WRITEFUNCTION "(3), " docs/libcurl/opts/CURLOPT_XFERINFODATA.3 0 → 100644 +46 −0 Original line number Diff line number Diff line .\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2014, 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 http://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 CURLOPT_XFERINFODATA 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" .SH NAME CURLOPT_XFERINFODATA \- custom pointer passed to the progress callback .SH SYNOPSIS #include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_XFERINFODATA, void *pointer); .SH DESCRIPTION Pass a \fIpointer\fP that will be untouched by libcurl and passed as the first argument in the progress callback set with \fICURLOPT_XFERINFOFUNCTION(3)\fP. This is an alias for \fICURLOPT_PROGRESSDATA(3)\fP. .SH DEFAULT The default value of this parameter is NULL. .SH PROTOCOLS All .SH EXAMPLE http://curl.haxx.se/libcurl/c/progressfunc.html .SH AVAILABILITY Added in 7.32.0 .SH RETURN VALUE Returns CURLE_OK .SH "SEE ALSO" .BR CURLOPT_XFERINFOFUNCTION "(3), " CURLOPT_XFERINFOFUNCTION "(3), " docs/libcurl/opts/CURLOPT_XFERINFOFUNCTION.3 0 → 100644 +81 −0 Original line number Diff line number Diff line .\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2014, 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 http://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 CURLOPT_XFERINFOFUNCTION 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" .SH NAME CURLOPT_XFERINFOFUNCTION \- callback to progress meter function .SH SYNOPSIS #include <curl/curl.h> int progress_callback(void *clientp, curl_off_t dltotal, curl_off_t dlnow, curl_off_t ultotal, curl_off_t ulnow); CURLcode curl_easy_setopt(CURL *handle, CURLOPT_XFERINFOFUNCTION, progress_callback); .SH DESCRIPTION Pass a pointer to your callback function, which should match the prototype shown above. This function gets called by libcurl instead of its internal equivalent with a frequent interval. While data is being transferred it will be called very frequently, and during slow periods like when nothing is being transferred it can slow down to about one call per second. \fIclientp\fP is the pointer set with \fICURLOPT_XFERINFODATA(3)\fP, it is not used by libcurl but is only passed along from the application to the callback. The callback gets told how much data libcurl will transfer and has transferred, in number of bytes. \fIdltotal\fP is the total number of bytes libcurl expects to download in this transfer. \fIdlnow\fP is the number of bytes downloaded so far. \fIultotal\fP is the total number of bytes libcurl expects to upload in this transfer. \fIulnow\fP is the number of bytes uploaded so far. Unknown/unused argument values passed to the callback will be set to zero (like if you only download data, the upload size will remain 0). Many times the callback will be called one or more times first, before it knows the data sizes so a program must be made to handle that. Returning a non-zero value from this callback will cause libcurl to abort the transfer and return \fICURLE_ABORTED_BY_CALLBACK\fP. If you transfer data with the multi interface, this function will not be called during periods of idleness unless you call the appropriate libcurl function that performs transfers. \fICURLOPT_NOPROGRESS(3)\fP must be set to 0 to make this function actually get called. .SH DEFAULT By default, libcurl has an internal progress meter. That's rarely wanted by users. .SH PROTOCOLS All .SH EXAMPLE http://curl.haxx.se/libcurl/c/progressfunc.html .SH AVAILABILITY Added in 7.32.0. This callback replaces \fICURLOPT_PROGRESSFUNCTION(3)\fP .SH RETURN VALUE Returns CURLE_OK. .SH "SEE ALSO" .BR CURLOPT_XFERINFODATA "(3), " CURLOPT_NOPROGRESS "(3), " Loading
docs/libcurl/opts/CURLOPT_HEADERFUNCTION.3 0 → 100644 +89 −0 Original line number Diff line number Diff line .\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2014, 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 http://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 CURLOPT_HEADERFUNCTION 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" .SH NAME CURLOPT_HEADERFUNCTION \- callback that receives header data .SH SYNOPSIS #include <curl/curl.h> size_t header_callback(char *buffer, size_t size, size_t nitems, void *userdata); CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HEADERFUNCTION, header_callback); .SH DESCRIPTION Pass a pointer to your callback function, which should match the prototype shown above. This function gets called by libcurl as soon as it has received header data. The header callback will be called once for each header and only complete header lines are passed on to the callback. Parsing headers is very easy using this. The size of the data pointed to by \fIptr\fP is \fIsize\fP multiplied with \fInmemb\fP. Do not assume that the header line is zero terminated! The pointer named \fIuserdata\fP is the one you set with the \fICURLOPT_HEADERDATA(3)\fP option. This callback function must return the number of bytes actually taken care of. If that amount differs from the amount passed in to your function, it'll signal an error to the library. This will cause the transfer to get aborted and the libcurl function in progress will return \fICURL_WRITE_ERROR\fP. A complete HTTP header that is passed to this function can be up to \fICURL_MAX_HTTP_HEADER\fP (100K) bytes. If this option is not set, or if it is set to NULL, but \fICURLOPT_HEADERDATA(3)\fP is set to anything but NULL, the function used to accept response data will be used instead. That is, it will be the function specified with \fICURLOPT_WRITEFUNCTION(3)\fP, or if it is not specified or NULL - the default, stream-writing function. It's important to note that the callback will be invoked for the headers of all responses received after initiating a request and not just the final response. This includes all responses which occur during authentication negotiation. If you need to operate on only the headers from the final response, you will need to collect headers in the callback yourself and use HTTP status lines, for example, to delimit response boundaries. When a server sends a chunked encoded transfer, it may contain a trailer. That trailer is identical to a HTTP header and if such a trailer is received it is passed to the application using this callback as well. There are several ways to detect it being a trailer and not an ordinary header: 1) it comes after the response-body. 2) it comes after the final header line (CR LF) 3) a Trailer: header among the regular response-headers mention what header(s) to expect in the trailer. For non-HTTP protocols like FTP, POP3, IMAP and SMTP this function will get called with the server responses to the commands that libcurl sends. .SH DEFAULT Nothing. .SH PROTOCOLS Used for all protocols with headers or meta-data concept: HTTP, FTP, POP3, IMAP, SMTP and more. .SH EXAMPLE TODO .SH AVAILABILITY Always .SH RETURN VALUE Returns CURLE_OK .SH "SEE ALSO" .BR CURLOPT_HEADERDATA "(3), " CURLOPT_WRITEFUNCTION "(3), "
docs/libcurl/opts/CURLOPT_XFERINFODATA.3 0 → 100644 +46 −0 Original line number Diff line number Diff line .\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2014, 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 http://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 CURLOPT_XFERINFODATA 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" .SH NAME CURLOPT_XFERINFODATA \- custom pointer passed to the progress callback .SH SYNOPSIS #include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_XFERINFODATA, void *pointer); .SH DESCRIPTION Pass a \fIpointer\fP that will be untouched by libcurl and passed as the first argument in the progress callback set with \fICURLOPT_XFERINFOFUNCTION(3)\fP. This is an alias for \fICURLOPT_PROGRESSDATA(3)\fP. .SH DEFAULT The default value of this parameter is NULL. .SH PROTOCOLS All .SH EXAMPLE http://curl.haxx.se/libcurl/c/progressfunc.html .SH AVAILABILITY Added in 7.32.0 .SH RETURN VALUE Returns CURLE_OK .SH "SEE ALSO" .BR CURLOPT_XFERINFOFUNCTION "(3), " CURLOPT_XFERINFOFUNCTION "(3), "
docs/libcurl/opts/CURLOPT_XFERINFOFUNCTION.3 0 → 100644 +81 −0 Original line number Diff line number Diff line .\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2014, 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 http://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 CURLOPT_XFERINFOFUNCTION 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" .SH NAME CURLOPT_XFERINFOFUNCTION \- callback to progress meter function .SH SYNOPSIS #include <curl/curl.h> int progress_callback(void *clientp, curl_off_t dltotal, curl_off_t dlnow, curl_off_t ultotal, curl_off_t ulnow); CURLcode curl_easy_setopt(CURL *handle, CURLOPT_XFERINFOFUNCTION, progress_callback); .SH DESCRIPTION Pass a pointer to your callback function, which should match the prototype shown above. This function gets called by libcurl instead of its internal equivalent with a frequent interval. While data is being transferred it will be called very frequently, and during slow periods like when nothing is being transferred it can slow down to about one call per second. \fIclientp\fP is the pointer set with \fICURLOPT_XFERINFODATA(3)\fP, it is not used by libcurl but is only passed along from the application to the callback. The callback gets told how much data libcurl will transfer and has transferred, in number of bytes. \fIdltotal\fP is the total number of bytes libcurl expects to download in this transfer. \fIdlnow\fP is the number of bytes downloaded so far. \fIultotal\fP is the total number of bytes libcurl expects to upload in this transfer. \fIulnow\fP is the number of bytes uploaded so far. Unknown/unused argument values passed to the callback will be set to zero (like if you only download data, the upload size will remain 0). Many times the callback will be called one or more times first, before it knows the data sizes so a program must be made to handle that. Returning a non-zero value from this callback will cause libcurl to abort the transfer and return \fICURLE_ABORTED_BY_CALLBACK\fP. If you transfer data with the multi interface, this function will not be called during periods of idleness unless you call the appropriate libcurl function that performs transfers. \fICURLOPT_NOPROGRESS(3)\fP must be set to 0 to make this function actually get called. .SH DEFAULT By default, libcurl has an internal progress meter. That's rarely wanted by users. .SH PROTOCOLS All .SH EXAMPLE http://curl.haxx.se/libcurl/c/progressfunc.html .SH AVAILABILITY Added in 7.32.0. This callback replaces \fICURLOPT_PROGRESSFUNCTION(3)\fP .SH RETURN VALUE Returns CURLE_OK. .SH "SEE ALSO" .BR CURLOPT_XFERINFODATA "(3), " CURLOPT_NOPROGRESS "(3), "
