.\" generated by cd2nroff 0.1 from CURLOPT_LOCALPORTRANGE.md
.TH CURLOPT_LOCALPORTRANGE 3 "2024-11-18" libcurl
.SH NAME
CURLOPT_LOCALPORTRANGE \- number of additional local ports to try
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_LOCALPORTRANGE,
                          long range);
.fi
.SH DESCRIPTION
Pass a long. The \fIrange\fP argument is the number of attempts libcurl makes
to find a working local port number. It starts with the given
\fICURLOPT_LOCALPORT(3)\fP and adds one to the number for each retry. Setting
this option to 1 or below makes libcurl only do one try for the exact port
number. Port numbers by nature are scarce resources that are busy at times so
setting this value to something too low might cause unnecessary connection
setup failures.
.SH DEFAULT
1
.SH PROTOCOLS
This functionality affects all supported protocols
.SH EXAMPLE
.nf
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);
  }
}
.fi
.SH AVAILABILITY
Added in curl 7.15.2
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH SEE ALSO
.BR CURLOPT_INTERFACE (3),
.BR CURLOPT_LOCALPORT (3)