FIOASYNC

Updated: April 19, 2023

Set or clear asynchronous I/O

Synopsis:

#include <sys/ioctl.h>

#define FIOASYNC        _IOW('f', 125, int)

Arguments to ioctl():

Argument Value
fd A file descriptor that you obtained by opening the device
request FIOASYNC
Additional argument A pointer to an int

Description:

This command sets or clears asynchronous I/O, depending on the value given. It's implemented as a call to fcntl() with the F_GETFL command (which becomes a DCMD_ALL_GETFLAGS devctl() command), followed by a call to fcntl() with the F_SETFL command (which becomes a DCMD_ALL_SETFLAGS devctl() command), setting or clearing O_ASYNC.

Note: The O_ASYNC flag isn't currently supported.

Input:

Zero to clear O_ASYNC, or nonzero to set it.

Output:

See also:

DCMD_ALL_GETFLAGS, DCMD_ALL_SETFLAGS

fcntl(), ioctl() in the QNX Neutrino C Library Reference