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)