Set or clear asynchronous I/O
#include <sys/ioctl.h> #define FIOASYNC _IOW('f', 125, int)
Argument | Value |
---|---|
fd | A file descriptor that you obtained by opening the device |
request | FIOASYNC |
Additional argument | A pointer to an int |
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.
Zero to clear O_ASYNC, or nonzero to set it.