NAME

       CURLOPT_UNIX_SOCKET_PATH - set 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. An empty string will result in an error at some point, it will not
       disable use of Unix domain sockets.

       When  enabled,  cURL will connect to the Unix domain socket instead of establishing a TCP connection to a
       host. Since no TCP connection is created, cURL does not need to 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.

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

       Given  that  you  have  an  nginx  server  running,  listening on /tmp/nginx.sock, you can request a HTTP
       resource with:

           curl_easy_setopt(curl_handle, CURLOPT_UNIX_SOCKET_PATH, "/tmp/nginx.sock");
           curl_easy_setopt(curl_handle, CURLOPT_URL, "http://localhost/");

       If you are on Linux and somehow have a need for paths larger than 107  bytes,  you  could  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/nginx.sock", dirfd);
           curl_easy_setopt(curl_handle, CURLOPT_UNIX_SOCKET_PATH, path);
           /* Be sure to keep dirfd valid until you discard the handle */

AVAILABILITY

       Since 7.40.0.

RETURN VALUE

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

SEE ALSO

       CURLOPT_OPENSOCKETFUNCTION(3), unix(7),