winch.c

UNIX编程高级环境（第二版）的终端IO部分的程序源码

#include    <signal.h>
#include    <termios.h>
#ifndef    TIOCGWINSZ
#include    <sys/ioctl.h>    /* 44BSD requires this too */
#endif
#include    "ourhdr.h"

static void    pr_winsize(int), sig_winch(int);

int
main(void)
{
    if (isatty(STDIN_FILENO) == 0)
        exit(1);

    if (signal(SIGWINCH, sig_winch) == SIG_ERR)
        err_sys("signal error");

    pr_winsize(STDIN_FILENO);    /* print initial size */
    for ( ; ; )                    /* and sleep forever */
        pause();
}

static void
pr_winsize(int fd)
{
    struct winsize    size;

    if (ioctl(fd, TIOCGWINSZ, (char *) &size) < 0)
        err_sys("TIOCGWINSZ error");
    printf("%d rows, %d columns\n", size.ws_row, size.ws_col);
}

static void
sig_winch(int signo)
{
    printf("SIGWINCH received\n");
    pr_winsize(STDIN_FILENO);
    return;
}