Xenix screenblanker - updated, with docs

[Wm E. Davidsen Jr]

  The first post was pretty ugly, here's one with a man page and
slightly better command interface. This blanks console screens on Xenix
after a period of inactivity.

#!/bin/sh
# shar:	Shell Archiver  (v1.27)
#
#	Run the following text with /bin/sh to create:
#	  scrnblank.1
#	  scrnblank
#
sed 's/^X//' << 'SHAR_EOF' > scrnblank.1 &&
X.TH scrnblank L local
X.SH NAME
Xscrnblank \- blank console after a period of inactivity
X.SH SYNOPSIS
Xscrnblank [ idle_mins [ inverval_sec ] ]
X.SH DESCRIPTION
XChecks periodically to see if all virtual consoles have been inactive
Xfor a length of time. If so the screen is blanked.
X
XIn your system rc file for user daemons (/etc/rc.d/7 directory) you can
Xadd the command "scrnblank &".
X.SH EXAMPLES
X  scrnblank
X  scrnblank 20
X  scrnblank 1 20
X.SH LIMITATIONS
XThis program requires a virtual console dedicated as a blank screen.
XThis is not usually a problem.
X.SH FILES
X/etc/rc.d/7/
X.SH AUTHOR
XBill Davidsen, davidsen at crdos1.crd.ge.com
X.SH Copyright
XCopyright 1990 by Bill Davidsen, all rights reserved. May be freely used
Xand distributed.
SHAR_EOF
chmod 0644 scrnblank.1 || echo "restore of scrnblank.1 fails"
sed 's/^X//' << 'SHAR_EOF' > scrnblank &&
X#!/bin/sh
X
X# blank screen for Xenix @(#)scrnblank - v1.3, 10/23/90 19:22:10
X
X# ================ customize begins
X# this is the screen number for the blank screen
X#	it should not be in use, preferably without a getty,
X#	since the cursor is not restored. ie. tty07 would be 7
XBLANK_SCR=7
X#=============== end of customize features
X
X# calling sequence:
X#	scrnblank [mins [interval]]
X#  Checks every {interval} seconds (default 60) to see if all console
X#  screens have been idle for {mins} minutes (default 5), and switches to
X#  the virtual screen selected below and blanks it.
X
X# This is the time to wait in minutes. 
X#	It may be set from the command line, too
Xif [ $# -ge 1 ]
Xthen	WAIT=$1
Xelse	WAIT=5
Xfi	#
X
X# this is the interval at which to test
Xif [ $# -ge 2 ]
Xthen	LOOPSEC=$2
Xelse	LOOPSEC=60
Xfi	#
X
X# Logic:
X#	the output of "who -u" is scanned to see if all console
X#	logins are over N minutes unused. Then the screen is blanked
X#	by setting cursor off and doing a clear screen.
X#	This program must be run from a tty
X
Xwhile true; do
X  who -u |
X  awk '
X  $2 ~ /tty[01][0-9]/ {
X    # Get the time field
X    time=substr($0, 38, 5)
X    if (time == "old") continue
X    split(time, xtime, ":")
X    idle = 60*xtime[1] + xtime[2]
X    if (WaitStart < idle) continue
X    Active = 1
X  }
X
X  END {
X    # really ugly way to change screens
X    if (!Active) {
X      # form the device name
X      OutDev=sprintf("/dev/tty%02d", BlankScrn)
X      # switch to the screen for blank use
X      printf("\r\033[%02dz", BlankScrn-1) > OutDev
X      # cursor off, CLS
X      printf("\r\033[=14;10C\f", BlankScrn) > OutDev
X    }
X  }' WaitStart=$WAIT BlankScrn=$BLANK_SCR -
X
X  sleep $LOOPSEC
Xdone
SHAR_EOF
chmod 0544 scrnblank || echo "restore of scrnblank fails"
exit 0

-- 
bill davidsen - davidsen at sixhub.uucp (uunet!crdgw1!sixhub!davidsen)
    sysop *IX BBS and Public Access UNIX
    moderator of comp.binaries.ibm.pc and 80386 mailing list
"Stupidity, like virtue, is its own reward" -me