CURLOPT_LOCALPORT - local port number to use for socket

NAME  SYNOPSIS  DESCRIPTION  DEFAULT  PROTOCOLS  EXAMPLE  AVAILABILITY  RETURN VALUE  SEE ALSO 

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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 result;
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);
result = 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)

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