NAME
siginterrupt
—
allow signals to interrupt system
calls
SYNOPSIS
#include
<signal.h>
int
siginterrupt
(int
sig, int flag);
DESCRIPTION
The
siginterrupt
()
function is used to change the system call restart behavior when a system
call is interrupted by the specified signal. If flag
is false (0), system calls will be restarted if they are interrupted by the
specified signal sig and no data has been transferred
yet. System call restart is the default behavior on
OpenBSD.
If flag is true (1), the restarting of
system calls is disabled. If a system call is interrupted by the specified
signal and no data has been transferred, the system call will return -1 with
the global variable errno set to
EINTR
. Interrupted system calls that have started
transferring data will return the amount of data actually transferred.
System call interrupt is the signal behavior found on
BSD systems prior to 4.2BSD
as well as most systems based upon AT&T System V
UNIX.
Programs may switch between restartable and
interruptible system call operation as often as desired in the execution of
a program. Issuing a
siginterrupt
()
call during the execution of a signal handler will cause the new action to
take place on the next signal to be caught.
RETURN VALUES
siginterrupt
() returns 0 on success or -1
if an invalid signal number has been specified.
SEE ALSO
HISTORY
The siginterrupt
() function appeared in
4.3BSD.