SIGINTERRUPT(3)SIGINTERRUPT(3)NAMEsiginterrupt - allow signals to interrupt system calls
SYNOPSIS
siginterrupt(sig, flag);
int sig, flag;
DESCRIPTION
Siginterrupt is used to change the system call restart behavior when a
system call is interrupted by the specified signal. If the flag is
false (0), then system calls will be restarted if they are interrupted
by the specified signal and no data has been transferred yet. System
call restart is the default behavior on 4.2 BSD.
If the flag is true (1), then 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 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 4.1 BSD and AT&T System V
UNIX systems.
Note that the new 4.2 BSD signal handling semantics are not altered in
any other way. Most notably, signal handlers always remain installed
until explicitly changed by a subsequent sigvec(2) call, and the signal
mask operates as documented in sigvec(2). Programs may switch between
restartable and interruptible system call operation as often as desired
in the execution of a program.
Issuing a siginterrupt(3) call during the execution of a signal handler
will cause the new action to take place on the next signal to be
caught.
NOTES
This library routine uses an extension of the sigvec(2) system call
that is not available in 4.2BSD, hence it should not be used if
backward compatibility is needed.
RETURN VALUE
A 0 value indicates that the call succeeded. A -1 value indicates that
an invalid signal number has been supplied.
SEE ALSOsigvec(2), sigblock(2), sigpause(2), sigsetmask(2).
4.3 Berkeley Distribution May 15, 1985 SIGINTERRUPT(3)