NAME

       CURLOPT_LOCALPORT - local port number to use for socket

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_LOCALPORT, long port);

DESCRIPTION

       Pass  a  long. This sets the local port number of the socket used for the connection. This can be used in
       combination with CURLOPT_INTERFACE(3) and you are recommended to use  CURLOPT_LOCALPORTRANGE(3)  as  well
       when this option is set. Valid port numbers are 1 - 65535.

DEFAULT

       0, disabled - use whatever the system thinks is fine

PROTOCOLS

       This functionality affects all supported protocols

EXAMPLE

       int main(void)
       {
         CURL *curl = curl_easy_init();
         if(curl) {
           CURLcode res;
           curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/foo.bin");
           curl_easy_setopt(curl, CURLOPT_LOCALPORT, 49152L);
           /* and try 20 more ports following that */
           curl_easy_setopt(curl, CURLOPT_LOCALPORTRANGE, 20L);
           res = curl_easy_perform(curl);
           curl_easy_cleanup(curl);
         }
       }

AVAILABILITY

       Added in curl 7.15.2

RETURN VALUE

       curl_easy_setopt(3) returns a CURLcode indicating success or error.

       CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).

SEE ALSO

       CURLINFO_LOCAL_PORT(3), CURLOPT_INTERFACE(3), CURLOPT_LOCALPORTRANGE(3)

libcurl                                            2025-03-05                               CURLOPT_LOCALPORT(3)