mirror of
https://github.com/moparisthebest/curl
synced 2024-11-17 23:15:08 -05:00
108 lines
3.7 KiB
Groff
108 lines
3.7 KiB
Groff
.\" **************************************************************************
|
|
.\" * _ _ ____ _
|
|
.\" * 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 CURLMOPT_TIMERFUNCTION 3 "17 Jun 2014" "libcurl 7.37.0" "curl_multi_setopt options"
|
|
.SH NAME
|
|
CURLMOPT_TIMERFUNCTION \- set callback to receive timeout values
|
|
.SH SYNOPSIS
|
|
.nf
|
|
#include <curl/curl.h>
|
|
|
|
int timer_callback(CURLM *multi, /* multi handle */
|
|
long timeout_ms, /* timeout in number of ms */
|
|
void *userp); /* private callback pointer */
|
|
|
|
CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_TIMERFUNCTION, timer_callback);
|
|
.SH DESCRIPTION
|
|
Pass a pointer to your callback function, which should match the prototype
|
|
shown above.
|
|
|
|
Certain features, such as timeouts and retries, require you to call libcurl
|
|
even when there is no activity on the file descriptors.
|
|
|
|
Your callback function \fBtimer_callback\fP should install a non-repeating
|
|
timer with an interval of \fBtimeout_ms\fP. When time that timer fires, call
|
|
either \fIcurl_multi_socket_action(3)\fP or \fIcurl_multi_perform(3)\fP,
|
|
depending on which interface you use.
|
|
|
|
A \fBtimeout_ms\fP value of -1 passed to this callback means you should delete
|
|
the timer. All other values are valid expire times in number of milliseconds.
|
|
|
|
The \fBtimer_callback\fP will only be called when the timeout expire time is
|
|
changed.
|
|
|
|
The \fBuserp\fP pointer is set with \fICURLMOPT_TIMERDATA(3)\fP.
|
|
|
|
The timer callback should return 0 on success, and -1 on error. This callback
|
|
can be used instead of, or in addition to, \fIcurl_multi_timeout(3)\fP.
|
|
|
|
\fBWARNING:\fP even if it feels tempting, avoid calling libcurl directly from
|
|
within the callback itself when the \fBtimeout_ms\fP value is zero, since it
|
|
risks triggering an unpleasant recursive behavior that immediately calls
|
|
another call to the callback with a zero timeout...
|
|
.SH DEFAULT
|
|
NULL
|
|
.SH PROTOCOLS
|
|
All
|
|
.SH EXAMPLE
|
|
.nf
|
|
static gboolean timeout_cb(gpointer user_data)
|
|
{
|
|
int running;
|
|
if(user_data) {
|
|
g_free(user_data);
|
|
curl_multi_setopt(curl_handle, CURLMOPT_TIMERDATA, NULL);
|
|
}
|
|
curl_multi_socket_action(multi, CURL_SOCKET_TIMEOUT, 0, &running);
|
|
return G_SOURCE_REMOVE;
|
|
}
|
|
|
|
static int timerfunc(CURLM *multi, long timeout_ms, void *userp)
|
|
{
|
|
guint *id = userp;
|
|
|
|
if(id)
|
|
g_source_remove(*id);
|
|
|
|
/* -1 means we should just delete our timer. */
|
|
if(timeout_ms == -1) {
|
|
g_free(id);
|
|
id = NULL;
|
|
}
|
|
else {
|
|
if(!id)
|
|
id = g_new(guint, 1);
|
|
*id = g_timeout_add(timeout_ms, timeout_cb, id);
|
|
}
|
|
curl_multi_setopt(multi, CURLMOPT_TIMERDATA, id);
|
|
return 0;
|
|
}
|
|
|
|
curl_multi_setopt(multi, CURLMOPT_TIMERFUNCTION, timerfunc);
|
|
.fi
|
|
.SH AVAILABILITY
|
|
Added in 7.16.0
|
|
.SH RETURN VALUE
|
|
Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.
|
|
.SH "SEE ALSO"
|
|
.BR CURLMOPT_TIMERDATA "(3), " CURLMOPT_SOCKETFUNCTION "(3), "
|