return 0 not null string when user has a ctty but no utmp entry

[unix-history] / usr / src / lib / libc / gen / siginterrupt.c

/*
 * Copyright (c) 1985 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)siginterrupt.c	5.2 (Berkeley) %G%";
#endif LIBC_SCCS and not lint

#include <signal.h>

/*
 * Set signal state to prevent restart of system calls
 * after an instance of the indicated signal.
 */
siginterrupt(sig, flag)
	int sig, flag;
{
	struct sigvec sv;
	int ret;

	if ((ret = sigvec(sig, 0, &sv)) < 0)
		return (ret);
	if (flag)
		sv.sv_flags |= SV_INTERRUPT;
	else
		sv.sv_flags &= ~SV_INTERRUPT;
	return (sigvec(sig, &sv, 0));
}