FIONBIO

Updated: April 19, 2023

Set or clear nonblocking I/O

Synopsis:

#include <sys/ioctl.h>

#define FIONBIO         _IOW('f', 126, int)

Arguments to ioctl():

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

Description:

This command sets or clears non-blocking I/O. It's implemented as a call to fcntl() with a command of F_GETFL (which becomes a DCMD_ALL_GETFLAGS devctl() command), followed by a call to fcntl() with a command of F_SETFL (which becomes a DCMD_ALL_SETFLAGS devctl() command), setting or clearing O_NONBLOCK.

Input:

Zero to clear O_NONBLOCK, or nonzero to set it.

Output:

None.

See also:

DCMD_ALL_GETFLAGS, DCMD_ALL_SETFLAGS

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