1--- 2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 3SPDX-License-Identifier: curl 4Title: CURLOPT_NOSIGNAL 5Section: 3 6Source: libcurl 7See-also: 8 - CURLOPT_TIMEOUT (3) 9Protocol: 10 - All 11Added-in: 7.10 12--- 13 14# NAME 15 16CURLOPT_NOSIGNAL - skip all signal handling 17 18# SYNOPSIS 19 20~~~c 21#include <curl/curl.h> 22 23CURLcode curl_easy_setopt(CURL *handle, CURLOPT_NOSIGNAL, long onoff); 24~~~ 25 26# DESCRIPTION 27 28If *onoff* is 1, libcurl uses no functions that install signal handlers or 29any functions that cause signals to be sent to the process. This option is 30here to allow multi-threaded Unix applications to still set/use all timeout 31options etc, without risking getting signals. 32 33If this option is set and libcurl has been built with the standard name 34resolver, timeouts cannot occur while the name resolve takes place. Consider 35building libcurl with the c-ares or threaded resolver backends to enable 36asynchronous DNS lookups, to enable timeouts for name resolves without the use 37of signals. 38 39Setting CURLOPT_NOSIGNAL(3) to 1 makes libcurl NOT ask the system to 40ignore SIGPIPE signals, which otherwise are sent by the system when trying to 41send data to a socket which is closed in the other end. libcurl makes an 42effort to never cause such SIGPIPE signals to trigger, but some operating 43systems have no way to avoid them and even on those that have there are some 44corner cases when they may still happen, contrary to our desire. 45 46# DEFAULT 47 480 49 50# %PROTOCOLS% 51 52# EXAMPLE 53 54~~~c 55int main(void) 56{ 57 CURL *curl = curl_easy_init(); 58 if(curl) { 59 CURLcode res; 60 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/"); 61 62 curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1L); 63 64 res = curl_easy_perform(curl); 65 66 curl_easy_cleanup(curl); 67 } 68} 69~~~ 70 71# %AVAILABILITY% 72 73# RETURN VALUE 74 75Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. 76
