GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: usr.bin/mg/ttyio.c Lines: 0 71 0.0 %
Date: 2017-11-07 Branches: 0 44 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: ttyio.c,v 1.37 2015/03/23 12:31:19 bcallah Exp $	*/
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/* This file is in the public domain. */
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/*
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 * POSIX terminal I/O.
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 *
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 * The functions in this file negotiate with the operating system for
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 * keyboard characters, and write characters to the display in a barely
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 * buffered fashion.
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 */
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#include <sys/ioctl.h>
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#include <sys/queue.h>
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#include <sys/time.h>
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#include <sys/types.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <poll.h>
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#include <signal.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <term.h>
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#include <termios.h>
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#include <unistd.h>
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#include "def.h"
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#define NOBUF	512			/* Output buffer size. */
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int	ttstarted;
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char	obuf[NOBUF];			/* Output buffer. */
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size_t	nobuf;				/* Buffer count. */
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struct	termios	oldtty;			/* POSIX tty settings. */
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struct	termios	newtty;
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int	nrow;				/* Terminal size, rows. */
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int	ncol;				/* Terminal size, columns. */
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/*
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 * This function gets called once, to set up the terminal.
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 * On systems w/o TCSASOFT we turn off off flow control,
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 * which isn't really the right thing to do.
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 */
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void
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ttopen(void)
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{
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	if (!isatty(STDIN_FILENO) || !isatty(STDOUT_FILENO))
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		panic("standard input and output must be a terminal");
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	if (ttraw() == FALSE)
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		panic("aborting due to terminal initialize failure");
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}
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/*
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 * This function sets the terminal to RAW mode, as defined for the current
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 * shell.  This is called both by ttopen() above and by spawncli() to
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 * get the current terminal settings and then change them to what
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 * mg expects.	Thus, tty changes done while spawncli() is in effect
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 * will be reflected in mg.
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 */
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int
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ttraw(void)
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{
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	if (tcgetattr(0, &oldtty) < 0) {
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		dobeep();
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		ewprintf("ttopen can't get terminal attributes");
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		return (FALSE);
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	}
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	(void)memcpy(&newtty, &oldtty, sizeof(newtty));
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	/* Set terminal to 'raw' mode and ignore a 'break' */
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	newtty.c_cc[VMIN] = 1;
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	newtty.c_cc[VTIME] = 0;
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	newtty.c_iflag |= IGNBRK;
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	newtty.c_iflag &= ~(BRKINT | PARMRK | INLCR | IGNCR | ICRNL | IXON);
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	newtty.c_oflag &= ~OPOST;
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	newtty.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
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	if (tcsetattr(0, TCSASOFT | TCSADRAIN, &newtty) < 0) {
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		dobeep();
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		ewprintf("ttopen can't tcsetattr");
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		return (FALSE);
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	}
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	ttstarted = 1;
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	return (TRUE);
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}
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/*
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 * This function gets called just before we go back home to the shell.
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 * Put all of the terminal parameters back.
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 * Under UN*X this just calls ttcooked(), but the ttclose() hook is in
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 * because vttidy() in display.c expects it for portability reasons.
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 */
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void
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ttclose(void)
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{
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	if (ttstarted) {
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		if (ttcooked() == FALSE)
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			panic("");	/* ttcooked() already printf'd */
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		ttstarted = 0;
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	}
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}
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/*
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 * This function restores all terminal settings to their default values,
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 * in anticipation of exiting or suspending the editor.
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 */
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int
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ttcooked(void)
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{
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	ttflush();
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	if (tcsetattr(0, TCSASOFT | TCSADRAIN, &oldtty) < 0) {
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		dobeep();
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		ewprintf("ttclose can't tcsetattr");
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		return (FALSE);
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	}
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	return (TRUE);
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}
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/*
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 * Write character to the display.  Characters are buffered up,
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 * to make things a little bit more efficient.
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 */
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int
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ttputc(int c)
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{
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	if (nobuf >= NOBUF)
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		ttflush();
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	obuf[nobuf++] = c;
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	return (c);
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}
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/*
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 * Flush output.
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 */
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void
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ttflush(void)
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{
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	ssize_t	 written;
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	char	*buf = obuf;
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	if (nobuf == 0)
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		return;
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	while ((written = write(fileno(stdout), buf, nobuf)) != nobuf) {
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		if (written == -1) {
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			if (errno == EINTR)
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				continue;
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			panic("ttflush write failed");
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		}
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		buf += written;
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		nobuf -= written;
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	}
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	nobuf = 0;
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}
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/*
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 * Read character from terminal. All 8 bits are returned, so that you
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 * can use a multi-national terminal.
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 */
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int
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ttgetc(void)
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{
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	char	c;
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	ssize_t	ret;
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	do {
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		ret = read(STDIN_FILENO, &c, 1);
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		if (ret == -1 && errno == EINTR) {
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			if (winch_flag) {
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				redraw(0, 0);
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				winch_flag = 0;
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			}
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		} else if (ret == -1 && errno == EIO)
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			panic("lost stdin");
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		else if (ret == 1)
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			break;
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	} while (1);
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	return ((int) c) & 0xFF;
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}
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/*
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 * Returns TRUE if there are characters waiting to be read.
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 */
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int
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charswaiting(void)
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{
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	int	x;
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	return ((ioctl(0, FIONREAD, &x) < 0) ? 0 : x);
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}
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/*
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 * panic - just exit, as quickly as we can.
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 */
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void
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panic(char *s)
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{
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	static int panicking = 0;
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	if (panicking)
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		return;
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	else
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		panicking = 1;
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	ttclose();
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	(void) fputs("panic: ", stderr);
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	(void) fputs(s, stderr);
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	(void) fputc('\n', stderr);
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	exit(1);
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}
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/*
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 * This function returns FALSE if any characters have showed up on the
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 * tty before 'msec' milliseconds.
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 */
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int
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ttwait(int msec)
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{
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	struct pollfd	pfd[1];
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	pfd[0].fd = 0;
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	pfd[0].events = POLLIN;
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	if ((poll(pfd, 1, msec)) == 0)
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		return (TRUE);
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	return (FALSE);
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}