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WATCH(8)		FreeBSD	System Manager's Manual		      WATCH(8)

NAME
     watch -- snoop on another tty line

SYNOPSIS
     watch [-cinotW] [-f snpdev] [tty]

DESCRIPTION
     Watch allows the user to examine all data coming through a	specified tty
     using the snp(4) device.  If the snp(4) device is not available, watch
     will attempt to load the module (snp).  Watch writes to standard output.

     The options are as	follows:

     -c	     Reconnect on close.  If the tty observed by watch is closed,
	     automatically reattach to the same	tty.  If this option is	not
	     specified,	watch will request a new tty if	running	in interactive
	     mode or exit if running without a controlling tty.

     -f	snpdev
	     If	this option is specified, watch	will use snpdev	as the snp(4)
	     device.  Without this option, watch will attempt to find the next
	     available snp(4) device.

     -i	     Force interactive mode.  Interactive mode is a default if watch
	     is	started	from a tty.  If	output is redirected to	a file,	inter-
	     active mode can still be requested	by specifying this option.

     -n	     Disable the ability to switch the watched tty interactively.
	     This disables both	change requests	made with <control-X> as well
	     as	automatic prompting when the current tty is closed or over-
	     flows.  In	all cases where	a prompt would be displayed, watch
	     will exit.	 The reconnect flags are unaffected by this option.
	     When this flag is used, <control-X> is passed through to the ter-
	     minal.

     -o	     Reconnect on overflow.  The behavior of watch if the observed tty
	     overflows is similar to the behavior if the observed tty is
	     closed.  For more info see	snp(4).

     -t	     Print the date and	time when observation of a given tty is
	     started.

     -W	     Allow write access	to observed tty.

     tty     Tty may be	specified as an	tty-style device, such as a pseudo tty
	     device, a virtual console,	or a serial line, etc.	Names may be
	     preceded by /dev/.

OPERATION
     While running in interactive mode,	all user input is discarded except
     for:

     <control-G>
	   Exit	watch.
     <control-W>
	   Clear screen.
     <control-X>
	   Change attached tty,	unless this feature is disabled, in which case
	   control-X is	passed to the terminal as with other control charac-
	   ters.

SEE ALSO
     pty(4), sio(4), snp(4), kldload(8)

BUGS
     No	terminal emulation is performed.  All user output is reproduced	as-is.

AUTHORS
     Ugen J.S. Antsilevich <ugen@NetVision.net.il>

HISTORY
     Watch first appeared in FreeBSD 2.1.

FreeBSD	10.1		       November	24, 2001		  FreeBSD 10.1

NAME | SYNOPSIS | DESCRIPTION | OPERATION | SEE ALSO | BUGS | AUTHORS | HISTORY

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