NAME

       curl_easy_recv - receives raw data on an "easy" connection

SYNOPSIS

       #include <curl/easy.h>

       CURLcode curl_easy_recv( CURL *curl, void *buffer, size_t buflen, size_t *n);

DESCRIPTION

       This  function  receives  raw  data  from  the  established  connection.  You  may  use  it together with
       curl_easy_send(3) to implement custom protocols using libcurl. This  functionality  can  be  particularly
       useful  if  you  use  proxies  and/or  SSL  encryption:  libcurl  will take care of proxy negotiation and
       connection set-up.

       buffer is a pointer to your buffer that will get the received data. buflen is the maximum amount of  data
       you can get in that buffer. The variable n points to will receive the number of received bytes.

       To  establish  the  connection, set CURLOPT_CONNECT_ONLY(3) option before calling curl_easy_perform(3) or
       curl_multi_perform(3). Note that curl_easy_recv(3) does not work on connections that were created without
       this option.

       The call will return CURLE_AGAIN if there is no data to read - the socket is used  in  non-blocking  mode
       internally. When CURLE_AGAIN is returned, use your operating system facilities like select(2) to wait for
       data. The socket may be obtained using curl_easy_getinfo(3) with CURLINFO_ACTIVESOCKET(3).

       Wait  on the socket only if curl_easy_recv(3) returns CURLE_AGAIN.  The reason for this is libcurl or the
       SSL library may internally cache some data, therefore you should call curl_easy_recv(3) until all data is
       read which would include any cached data.

       Furthermore if you wait on the socket and it tells you there  is  data  to  read,  curl_easy_recv(3)  may
       return  CURLE_AGAIN  if the only data that was read was for internal SSL processing, and no other data is
       available.

AVAILABILITY

       Added in 7.18.2.

RETURN VALUE

       On success, returns CURLE_OK, stores the received data into buffer, and the number of bytes  it  actually
       read into *n.

       On failure, returns the appropriate error code.

       The  function  may  return  CURLE_AGAIN. In this case, use your operating system facilities to wait until
       data can be read, and retry.

       Reading exactly 0 bytes indicates a closed connection.

       If  there's  no  socket  available  to  use  from  the   previous   transfer,   this   function   returns
       CURLE_UNSUPPORTED_PROTOCOL.

EXAMPLE

       See sendrecv.c in docs/examples directory for usage example.

SEE ALSO

       curl_easy_setopt(3), curl_easy_perform(3), curl_easy_getinfo(3), curl_easy_send(3)

libcurl 7.58.0                                  December 18, 2016                              curl_easy_recv(3)