CURLOPT_LOCALPORTRANGE

Section: C Library Functions (3)
Updated: 202-0-19
Index Return to Main Contents

---

 

NAME

CURLOPT_LOCALPORTRANGE - number of additional local ports to try  

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_LOCALPORTRANGE,
                          long range);

 

DESCRIPTION

Pass a long. The range argument is the number of attempts libcurl makes to find a working local port number. It starts with the given CURLOPT_LOCALPORT(3) 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.  

DEFAULT

1  

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

CURLOPT_INTERFACE(3), CURLOPT_LOCALPORT(3)

---

 

Index

NAME

SYNOPSIS

DESCRIPTION

DEFAULT

PROTOCOLS

EXAMPLE

AVAILABILITY

RETURN VALUE

SEE ALSO