| 12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485 |
- .\" **************************************************************************
- .\" * _ _ ____ _
- .\" * 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 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 CURLOPT_PROGRESSFUNCTION 3 "February 03, 2016" "libcurl 7.61.1" "curl_easy_setopt options"
- .SH NAME
- CURLOPT_PROGRESSFUNCTION \- callback to progress meter function
- .SH SYNOPSIS
- #include <curl/curl.h>
- int progress_callback(void *clientp,
- double dltotal,
- double dlnow,
- double ultotal,
- double ulnow);
- CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROGRESSFUNCTION, progress_callback);
- .SH DESCRIPTION
- Pass a pointer to your callback function, which should match the prototype
- shown above.
- We encourage users to use the newer \fICURLOPT_XFERINFOFUNCTION(3)\fP instead,
- if you can.
- 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_PROGRESSDATA(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
- https://curl.haxx.se/libcurl/c/progressfunc.html
- .SH AVAILABILITY
- Always
- .SH RETURN VALUE
- Returns CURLE_OK.
- .SH "SEE ALSO"
- .BR CURLOPT_VERBOSE "(3), " CURLOPT_NOPROGRESS "(3), "
|
