CURLOPT_UNIX_SOCKET_PATH(3)

1CURLOPT_UNIX_SOCKET_PATH(3)curl_easy_setopt optionsCURLOPT_UNIX_SOCKET_PATH(3)
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NAME

6       CURLOPT_UNIX_SOCKET_PATH - set Unix domain socket
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SYNOPSIS

9       #include <curl/curl.h>
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11       CURLcode  curl_easy_setopt(CURL *handle, CURLOPT_UNIX_SOCKET_PATH, char
12       *path);
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DESCRIPTION

15       Enables the use of Unix domain sockets as connection endpoint and  sets
16       the  path  to  path. If path is NULL, then Unix domain sockets are dis‐
17       abled. An empty string will result in an error at some point,  it  will
18       not disable use of Unix domain sockets.
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20       When  enabled,  curl  will connect to the Unix domain socket instead of
21       establishing a TCP connection to a host. Since  no  TCP  connection  is
22       created, curl does not need to resolve the DNS hostname in the URL.
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24       The  maximum  path length on Cygwin, Linux and Solaris is 107. On other
25       platforms it might be even less.
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27       Proxy and TCP options such as CURLOPT_TCP_NODELAY(3) are not supported.
28       Proxy  options  such as CURLOPT_PROXY(3) have no effect either as these
29       are TCP-oriented, and asking a proxy server to  connect  to  a  certain
30       Unix domain socket is not possible.
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32       The  application  does not have to keep the string around after setting
33       this option.
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DEFAULT

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

39       All protocols except for file:// and FTP are supported in theory. HTTP,
40       IMAP,  POP3 and SMTP should in particular work (including their SSL/TLS
41       variants).
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EXAMPLE

44       Given that you have an nginx  server  running,  listening  on  /tmp/ng‐
45       inx.sock, you can request an HTTP resource with:
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47           curl_easy_setopt(curl_handle, CURLOPT_UNIX_SOCKET_PATH, "/tmp/nginx.sock");
48           curl_easy_setopt(curl_handle, CURLOPT_URL, "http://localhost/");
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50       If  you  are on Linux and somehow have a need for paths larger than 107
51       bytes, you could use the proc filesystem to bypass the limitation:
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53           int dirfd = open(long_directory_path_to_socket, O_DIRECTORY | O_RDONLY);
54           char path[108];
55           snprintf(path, sizeof(path), "/proc/self/fd/%d/nginx.sock", dirfd);
56           curl_easy_setopt(curl_handle, CURLOPT_UNIX_SOCKET_PATH, path);
57           /* Be sure to keep dirfd valid until you discard the handle */
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AVAILABILITY

60       Since 7.40.0.
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RETURN VALUE

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