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)