Provided by: libcurl4-doc_7.58.0-2ubuntu3.24_all bug

NAME

       CURLOPT_INTERLEAVEFUNCTION - callback function for RTSP interleaved data

SYNOPSIS

       #include <curl/curl.h>

       size_t interleave_callback(void *ptr, size_t size, size_t nmemb,
                                  void *userdata);

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_INTERLEAVEFUNCTION,
                                 interleave_callback);

DESCRIPTION

       Pass a pointer to your callback function, which should match the prototype shown above.

       This  callback  function  gets  called  by  libcurl as soon as it has received interleaved RTP data. This
       function gets called for each $ block and therefore contains exactly one upper-layer protocol unit  (e.g.
       one RTP packet). Curl writes the interleaved header as well as the included data for each call. The first
       byte is always an ASCII dollar sign. The dollar sign is followed by a one  byte  channel  identifier  and
       then a 2 byte integer length in network byte order. See RFC2326 Section 10.12 for more information on how
       RTP interleaving behaves. If unset or set to NULL, curl will use the default write function.

       Interleaved RTP poses some challenges for the client application. Since the stream data  is  sharing  the
       RTSP  control  connection,  it is critical to service the RTP in a timely fashion. If the RTP data is not
       handled quickly, subsequent response processing may become unreasonably delayed and  the  connection  may
       close.  The application may use CURL_RTSPREQ_RECEIVE to service RTP data when no requests are desired. If
       the application makes a request, (e.g.  CURL_RTSPREQ_PAUSE) then the response handler  will  process  any
       pending RTP data before marking the request as finished.

       The CURLOPT_WRITEDATA(3) is passed in the userdata argument in the callback.

DEFAULT

       NULL, the interleave data is then passed to the regular write function: CURLOPT_WRITEFUNCTION(3).

PROTOCOLS

       RTSP

EXAMPLE

       static size_t rtp_write(void *ptr, size_t size, size_t nmemb, void *user)
       {
         struct local *l = (struct local *)user;
         /* take care of the packet in 'ptr', then return... */
         return size * nmemb;
       }
       {
         struct local rtp_data;
         curl_easy_setopt(curl, CURLOPT_INTERLEAVEFUNCTION, rtp_write);
         curl_easy_setopt(curl, CURLOPT_INTERLEAVEDATA, &rtp_data);
       }

AVAILABILITY

       Added in 7.20.0

RETURN VALUE

       Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

SEE ALSO

       CURLOPT_INTERLEAVEDATA(3), CURLOPT_RTSP_REQUEST(3),