Using this function, you can explicitly mark a running connection to get
paused, and you can unpause a connection that was previously paused.
A connection can made to pause by using this function or by letting the read
or the write callbacks return the proper magic return code
(CURL_READFUNC_PAUSE and CURL_WRITEFUNC_PAUSE). A write callback
that returns pause signals to the library that it couldn't take care of any
data at all, and that data will then be delivered again to the callback when
the writing is later unpaused.
NOTE: while it may feel tempting, take care and notice that you cannot call
this function from another thread.
When this function is called to unpause reading, the chance is high that you
will get your write callback called before this function returns.
The handle argument is of course identifying the handle that operates on
the connection you want to pause or unpause.
The bitmask argument is a set of bits that sets the new state of the
connection. The following bits can be used:
- CURLPAUSE_RECV
-
Pause receiving data. There will be no data received on this conneciton until
this function is called again without this bit set. Thus, the write callback
(CURLOPT_WRITEFUNCTION) won't be called.
- CURLPAUSE_SEND
-
Pause sending data. There will be no data sent on this connection until this
function is called again without this bit set. Thus, the read callback
(CURLOPT_READFUNCTION) won't be called.
- CURLPAUSE_ALL
-
Convenience define that pauses both directions.
- CURLPAUSE_CONT
-
Convenience define that unpauses both directions