Unknown option: "-3" Unix manual page for CURLOPT_NOSIGNAL. (host=minya system=Darwin)
CURLOPT_NOSIGNAL(3)        curl_easy_setopt options        CURLOPT_NOSIGNAL(3)

NAME
       CURLOPT_NOSIGNAL - skip all signal handling

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_NOSIGNAL, long onoff);

DESCRIPTION
       If  onoff  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 CURLOPT_NOSIGNAL(3) 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 SIGPIPEs 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 CURLAUTH_NTLM_WB authentication could
       cause a SIGCHLD signal to be raised.

DEFAULT
       0

AVAILABILITY
       Added in 7.10

RETURN VALUE
       Returns  CURLE_OK  if the option is supported, and CURLE_UNKNOWN_OPTION
       if not.

libcurl 7.54.0                 February 03, 2016           CURLOPT_NOSIGNAL(3)