2 * Copyright (c) 1981, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
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14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
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18 * may be used to endorse or promote products derived from this software
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30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 static char sccsid[] = "@(#)tstp.c 8.3 (Berkeley) 5/4/94";
46 * stop_signal_handler --
47 * Handle stop signals.
50 __stop_signal_handler(signo)
56 /* Get the current terminal state (which the user may have changed). */
57 if (tcgetattr(__tty_fileno, &save))
61 * Block window change and timer signals. The latter is because
62 * applications use timers to decide when to repaint the screen.
64 (void)sigemptyset(&set);
65 (void)sigaddset(&set, SIGALRM);
66 (void)sigaddset(&set, SIGWINCH);
67 (void)sigprocmask(SIG_BLOCK, &set, &oset);
70 * End the window, which also resets the terminal state to the
75 /* Unblock SIGTSTP. */
76 (void)sigemptyset(&set);
77 (void)sigaddset(&set, SIGTSTP);
78 (void)sigprocmask(SIG_UNBLOCK, &set, NULL);
81 __restore_stophandler();
82 (void)kill(0, SIGTSTP);
86 /* Reset the curses SIGTSTP signal handler. */
89 /* save the new "default" terminal state */
90 (void)tcgetattr(__tty_fileno, &__orig_termios);
92 /* Reset the terminal state to the mode just before we stopped. */
93 (void)tcsetattr(__tty_fileno, __tcaction ?
94 TCSASOFT | TCSADRAIN : TCSADRAIN, &save);
96 /* Restart the screen. */
99 /* Repaint the screen. */
102 /* Reset the signals. */
103 (void)sigprocmask(SIG_SETMASK, &oset, NULL);
106 static void (*otstpfn)() = SIG_DFL;
109 * Set the TSTP handler.
114 otstpfn = signal(SIGTSTP, __stop_signal_handler);
118 * Restore the TSTP handler.
121 __restore_stophandler()
123 (void)signal(SIGTSTP, otstpfn);
126 /* For compatibility */
128 void tstp() { __stop_signal_handler(SIGTSTP); }