curl/docs/libcurl/opts/CURLOPT_NOSIGNAL.3

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.TH CURLOPT_NOSIGNAL 3 "16 Jun 2014" libcurl libcurl
.SH NAME
CURLOPT_NOSIGNAL \- skip all signal handling
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_NOSIGNAL, long onoff);
.fi
.SH DESCRIPTION
If \fIonoff\fP is 1, libcurl will not use any functions that install signal
handlers or any functions that cause signals to be sent to the process. This
option is here to allow multi-threaded unix applications to still set/use all
timeout options etc, without risking getting signals.

If this option is set and libcurl has been built with the standard name
resolver, timeouts will not occur while the name resolve takes place.
Consider building libcurl with the c-ares or threaded resolver backends to
enable asynchronous DNS lookups, to enable timeouts for name resolves without
the use of signals.

Setting \fICURLOPT_NOSIGNAL(3)\fP to 1 makes libcurl NOT ask the system to
ignore SIGPIPE signals, which otherwise are sent by the system when trying to
send data to a socket which is closed in the other end. libcurl makes an
effort to never cause such SIGPIPE signals to trigger, but some operating
systems have no way to avoid them and even on those that have there are some
corner cases when they may still happen, contrary to our desire. In addition,
using \fICURLAUTH_NTLM_WB\fP authentication could cause a SIGCHLD signal to be
raised.
.SH DEFAULT
0
.SH PROTOCOLS
All
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");

  curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1L);

  ret = curl_easy_perform(curl);

  curl_easy_cleanup(curl);
}
.fi
.SH AVAILABILITY
Added in 7.10
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH SEE ALSO
.BR CURLOPT_TIMEOUT "(3), "