bionic (3) CURLOPT_INTERFACE.3.gz

NAME

       CURLOPT_INTERFACE - source interface for outgoing traffic

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_INTERFACE, char *interface);

DESCRIPTION

       Pass  a  char * as parameter. This sets the interface name to use as outgoing network interface. The name
       can be an interface name, an IP address, or a host name.

       If the parameter starts with "if!" then it is treated as only as interface name and no attempt will  ever
       be  named  to  do treat it as an IP address or to do name resolution on it.  If the parameter starts with
       "host!" it is treated as either an IP address or  a  hostname.   Hostnames  are  resolved  synchronously.
       Using  the if! format is highly recommended when using the multi interfaces to avoid allowing the code to
       block.   If  "if!"  is  specified  but  the   parameter   does   not   match   an   existing   interface,
       CURLE_INTERFACE_FAILED is returned from the libcurl function used to perform the transfer.

       The application does not have to keep the string around after setting this option.

DEFAULT

       NULL, use whatever the TCP stack finds suitable

PROTOCOLS

       All

EXAMPLE

       CURL *curl = curl_easy_init();
       if(curl) {
         curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/foo.bin");

         curl_easy_setopt(curl, CURLOPT_INTERFACE, "eth0");

         ret = curl_easy_perform(curl);

         curl_easy_cleanup(curl);
       }

AVAILABILITY

       The "if!" and "host!" syntax was added in 7.24.0.

RETURN VALUE

       Returns CURLE_OK on success or CURLE_OUT_OF_MEMORY if there was insufficient heap space.

SEE ALSO

       CURLOPT_SOCKOPTFUNCTION(3), CURLOPT_TCP_NODELAY(3),