debian man page for io_wait

io_wait(3)						     Library Functions Manual							io_wait(3)

NAME
       io_wait - wait for events

SYNTAX
       #include <io.h>

       void io_wait();

DESCRIPTION
       io_wait()  checks  the  descriptors  that  the  program	is  interested in to see whether any of them are ready. If none of them are ready,
       io_wait() tries to pause until one of them is ready, so that it does not take time away from other programs running on the same computer.

       io_wait pays attention to timeouts: if a descriptor reaches its timeout, and the program is interested in reading or writing that  descrip-
       tor, io_wait will return promptly.

       Under  some  circumstances,  io_wait will return even though no interesting descriptors are ready. Do not assume that a descriptor is ready
       merely because io_wait has returned.

       io_wait is not interrupted by the delivery of a signal. Programs that expect interruption are unreliable: they will block if the same  sig-
       nal is delivered a moment before io_wait. The correct way to handle signals is with the self-pipe trick.

SEE ALSO
       io_waituntil(3), io_check(3), io_wantread(3), io_wantwrite(3), io_fd(3)

																	io_wait(3)