curl/docs/libcurl/opts/CURLOPT_LOCALPORT.3

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.TH CURLOPT_LOCALPORT 3 "19 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options"
.SH NAME
CURLOPT_LOCALPORT \- local port number to use for socket
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_LOCALPORT, long port);
.fi
.SH DESCRIPTION
Pass a long. This sets the local port number of the socket used for the
connection. This can be used in combination with \fICURLOPT_INTERFACE(3)\fP
and you are recommended to use \fICURLOPT_LOCALPORTRANGE(3)\fP as well when
this option is set. Valid port numbers are 1 - 65535.
.SH DEFAULT
0, disabled - use whatever the system thinks is fine
.SH PROTOCOLS
All
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
  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);
  ret = curl_easy_perform(curl);
  curl_easy_cleanup(curl);
}
.fi
.SH AVAILABILITY
Added in 7.15.2
.SH RETURN VALUE
Returns CURLE_OK
.SH "SEE ALSO"
.BR CURLOPT_LOCALPORTRANGE "(3), " CURLOPT_INTERFACE "(3), "