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FLASHER(1)		     General Commands Manual		      FLASHER(1)

NAME
     flasher -	 flash keyboard LEDs to indicate file writes

SYNOPSIS
     flasher [ -u seconds ] [ -k /dev/ttyXX ] -{c|n|s} file1:file2:...:fileN

DESCRIPTION
     flasher  monitors changes to one or more files, and indicates the number of
     writes to these files by briefly flashing	a  console  LED  once  for  each
     write.   The  flashing sequence is repeated, after a brief pause, until the
     files have been read.  As the files are subsequently read,  the  number  of
     LED  flashes is reduced.  When all monitored files have been read, the con-
     sole LED will be disabled.

     The most obvious use is to monitor specific system log or mail files.

     Multiple LEDs can be used. Each possible LED (-c, -n or -s) takes a list of
     colon-separated file arguments.  For example, when invoked as:

	    # flasher -s /var/log/messages:/var/mail/root

     the Scroll Lock LED will flash once for each write made to either of  these
     files, until the files are read.  When /var/log/messages has been read, the
     Scroll  Lock  LED	will continue to flash once for each write that has been
     made to /var/mail/root, until it also has been read.

     The list of files can include files that don't yet exist.

     To terminate the daemon, run:

	    # kill `cat /var/run/flasher.pid`

X11
     flasher was designed to use the console to indicate  file	activity.   When
     running  flasher in an X11 environment, it may be helpful to use the -k op-
     tion to specify what virtual terminal X11 is running  under.  For	example,
     use

	    # flasher -k /dev/ttyv3 ...

     when running X11 on FreeBSD on virtual terminal 4.

     Similarly,  when using X11 on virtual terminal 8 on Linux, start the daemon
     using:

	    # flasher -k /dev/tty8 ...

OPTIONS
     -c     Indicate writes to the specified file using the Caps Lock LED.

     -k /dev/ttyXX
	    Use the specified tty (/dev/ttyXX) instead of the console.

     -n     Indicate writes to the specified file using the Num Lock LED.

     -s     Indicate writes to the specified file using the Scroll Lock LED.

     -u number
	    Scans the specified files for changes every  `number'  seconds  (de-
	    fault: 60).

EXAMPLES
     The   following  example  will  flash  the  Scroll  Lock  LED  to	indicate
     /var/log/messages	writes,  and  the   Num   Lock	 LED   for   writes   to
     /var/mail/root:

	    # flasher -s /var/log/messages -n /var/mail/root

     The  following  example  will flash the Caps Lock LED to indicate writes to
     either /var/log/httpd-error.log or /var/mail/root, and flash the  Num  Lock
     LED to indicate writes to /var/log/messages.

	    #	  flasher    -n    /var/log/messages	-c    /var/log/httpd-er-
	    ror.log:/var/mail/root

FILES
     /var/run/flasher.pid - flasher lock file

DIAGNOSTICS
     flasher must be run as the super-user.

     Relative pathnames will be converted to absolute pathnames.

     After the program has daemonized, any messages will be sent to syslog.

AUTHOR
     Murray Nesbitt (websrc@nesbitt.ca)

								      FLASHER(1)

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