dispatch_block_testcancel

dispatch2

Function dispatch_block_testcancel 

Source 
pub unsafe extern "C" fn dispatch_block_testcancel(
    block: dispatch_block_t,
) -> isize
Expand description

Tests whether the given dispatch block object has been canceled.

Parameter block: The dispatch block object to test. The result of passing NULL or a block object not returned by one of the dispatch_block_create* functions is undefined.

Returns: Non-zero if canceled and zero if not canceled.