NAME

       CURLOPT_UNIX_SOCKET_PATH - Unix domain socket

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_UNIX_SOCKET_PATH, char *path);

DESCRIPTION

       Enables the use of Unix domain sockets as connection endpoint and sets the path to path. If path is NULL,
       then Unix domain sockets are disabled.

       When enabled, curl connects to the Unix domain socket instead of establishing a  TCP  connection  to  the
       host. Since no network connection is created, curl does not resolve the DNS hostname in the URL.

       The maximum path length on Cygwin, Linux and Solaris is 107. On other platforms it might be even less.

       Proxy  and  TCP  options  such  as  CURLOPT_TCP_NODELAY(3)  are  not  supported.  Proxy  options  such as
       CURLOPT_PROXY(3) have no effect either as these are TCP-oriented, and asking a proxy server to connect to
       a certain Unix domain socket is not possible.

       The application does not have to keep the string around after setting this option.

DEFAULT

       Default is NULL, meaning that no Unix domain sockets are used.

PROTOCOLS

       All  protocols  except  for  FILE  and  FTP  are supported in theory. HTTP, IMAP, POP3 and SMTP should in
       particular work (including their SSL/TLS variants).

EXAMPLE

       int main(void)
       {
         CURL *curl = curl_easy_init();
         if(curl) {
           curl_easy_setopt(curl, CURLOPT_UNIX_SOCKET_PATH, "/tmp/httpd.sock");
           curl_easy_setopt(curl, CURLOPT_URL, "http://localhost/");

           curl_easy_perform(curl);
         }
       }

       If you are on Linux and somehow have a need for paths larger  than  107  bytes,  you  can  use  the  proc
       filesystem to bypass the limitation:

         int dirfd = open(long_directory_path_to_socket, O_DIRECTORY | O_RDONLY);
         char path[108];
         snprintf(path, sizeof(path), "/proc/self/fd/%d/httpd.sock", dirfd);
         curl_easy_setopt(curl_handle, CURLOPT_UNIX_SOCKET_PATH, path);
         /* Be sure to keep dirfd valid until you discard the handle */

AVAILABILITY

       Added in 7.40.0.

RETURN VALUE

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

SEE ALSO

       CURLOPT_ABSTRACT_UNIX_SOCKET(3), CURLOPT_OPENSOCKETFUNCTION(3), unix(7)