#include "apue.h"#include <termios.h>#ifndef	TIOCGWINSZ#include <sys/ioctl.h>#endifstatic voidpr_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 voidsig_winch(int signo){	printf("SIGWINCH received\n");	pr_winsize(STDIN_FILENO);}intmain(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();}