curlopt_interleavefunction(3) [mojave man page]

CURLOPT_INTERLEAVEFUNCTION(3)				     curl_easy_setopt options				     CURLOPT_INTERLEAVEFUNCTION(3)

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 crit-
       ical 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.

DEFAULT

       NULL

PROTOCOLS

       RTSP

EXAMPLE

       TODO

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_INTERLEAVEFUNCTION(3), CURLOPT_RTSP_REQUEST(3),

libcurl 7.54.0							 February 03, 2016				     CURLOPT_INTERLEAVEFUNCTION(3)

CURLOPT_WRITEFUNCTION(3)				     curl_easy_setopt options					  CURLOPT_WRITEFUNCTION(3)

NAME

       CURLOPT_WRITEFUNCTION - set callback for writing received data

SYNOPSIS

       #include <curl/curl.h>

       size_t write_callback(char *ptr, size_t size, size_t nmemb, void *userdata);

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_WRITEFUNCTION, write_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 there is data received that needs to be saved.  ptr points to the delivered data,
       and the size of that data is size multiplied with nmemb.

       The callback function will be passed as much data as possible in all invokes, but you must not make any assumptions. It may be one byte, it
       may  be	thousands.  The  maximum  amount  of  body  data  that	will be passed to the write callback is defined in the curl.h header file:
       CURL_MAX_WRITE_SIZE (the usual default is 16K). If CURLOPT_HEADER(3) is enabled, which makes header data get passed to the write  callback,
       you can get up to CURL_MAX_HTTP_HEADER bytes of header data passed into it. This usually means 100K.

       This function may be called with zero bytes data if the transferred file is empty.

       The data passed to this function will not be zero terminated!

       Set the userdata argument with the CURLOPT_WRITEDATA(3) option.

       Your  callback  should  return  the  number of bytes actually taken care of. If that amount differs from the amount passed to your callback
       function, it'll signal an error condition to the library. This will cause the transfer to get aborted and the libcurl  function	used  will
       return CURLE_WRITE_ERROR.

       If  your  callback  function returns CURL_WRITEFUNC_PAUSE it will cause this transfer to become paused.	See curl_easy_pause(3) for further
       details.

       Set this option to NULL to get the internal default function used instead of your callback. The internal default function  will	write  the
       data to the FILE * given with CURLOPT_WRITEDATA(3).

DEFAULT

       libcurl will use 'fwrite' as a callback by default.

PROTOCOLS

       For all protocols

AVAILABILITY

       Support for the CURL_WRITEFUNC_PAUSE return code was added in version 7.18.0.

RETURN VALUE

       This will return CURLE_OK.

EXAMPLE

       A  common technique is to use this callback to store the incoming data into a dynamically growing allocated buffer. Like in the getinmemory
       example: https://curl.haxx.se/libcurl/c/getinmemory.html

SEE ALSO

       CURLOPT_WRITEDATA(3), CURLOPT_READFUNCTION(3),

libcurl 7.54.0							 February 03, 2016					  CURLOPT_WRITEFUNCTION(3)