CURLOPT_INTERFACE(3)       curl_easy_setopt options       CURLOPT_INTERFACE(3)

NAME
       CURLOPT_INTERFACE - source interface for outgoing traffic

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_INTERFACE, char *inter-
       face);

DESCRIPTION
       Pass a char * as parameter. This sets the interface name to use as out-
       going  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 inter-
       face  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
       TODO

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 insuf-
       ficient heap space.

SEE ALSO
       CURLOPT_SOCKOPTFUNCTION(3), CURLOPT_TCP_NODELAY(3),

libcurl 7.54.0                 December 21, 2016          CURLOPT_INTERFACE(3)