tty/demo_SIGWINCH.c

This is tty/demo_SIGWINCH.c (Listing 62-5, page 1320), an example from the book, The Linux Programming Interface.

The source code file is copyright 2024, Michael Kerrisk, and is licensed under the GNU General Public License, version 3.

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  Cover of The Linux Programming Interface

Function list (Bold in this list means a function is not static)

/* demo_SIGWINCH.c

   Demonstrate the generation of the SIGWINCH signal. A handler for SIGWINCH
   allows the program to discover terminal window size changes; when that
   signal is generated, the program displays the new terminal window size.
*/
#include <signal.h>
#include <termios.h>
#include <sys/ioctl.h>
#include "tlpi_hdr.h"
static void
sigwinchHandler(int sig)
{
}
int
main(int argc, char *argv[])
{
    struct winsize ws;
    struct sigaction sa;

    sigemptyset(&sa.sa_mask);
    sa.sa_flags = 0;
    sa.sa_handler = sigwinchHandler;
    if (sigaction(SIGWINCH, &sa, NULL) == -1)
        errExit("sigaction");

    for (;;) {
        pause();                        /* Wait for SIGWINCH signal */

        if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) == -1)
            errExit("ioctl");
        printf("Caught SIGWINCH, new window size: "
                "%d rows * %d columns\n", ws.ws_row, ws.ws_col);
    }
}

 

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