From jrj@gandalf.cc.purdue.edu Fri Jul 25 13:44 EDT 1997 Received: from FCRFV2.NCIFCRF.GOV (fcrfv2.ncifcrf.gov [129.43.51.3]) by ncisun1-nf0.ncifcrf.gov (8.8.5/8.7.3) with SMTP id NAA26083 for ; Fri, 25 Jul 1997 13:44:44 -0400 (EDT) Received: from gandalf.cc.purdue.edu by FCRFV1.NCIFCRF.GOV with ESMTP for toms@alum.mit.edu; Fri, 25 Jul 1997 13:50:08 -0400 Received: from gandalf.cc.purdue.edu (jrj@localhost [127.0.0.1]) by gandalf.cc.purdue.edu (8.8.3/8.8.3) with ESMTP id MAA13245; Fri, 25 Jul 1997 12:44:59 -0500 (EST) Resent-Message-Id: <199707251744.NAA26083@ncisun1-nf0.ncifcrf.gov> Resent-Date: Fri, 25 Jul 1997 13:49:53 -0400 Resent-From: toms@fcrfv2.ncifcrf.gov Resent-To: toms@ncisun1-nf0.ncifcrf.gov Message-Id: <199707251744.MAA13245@gandalf.cc.purdue.edu> To: jsh@rd.qms.com Cc: toms@alum.mit.edu Subject: Tweaks for "atchange" and "eh" Reply-to: jrj@cc.purdue.edu Date: Fri, 25 Jul 1997 12:44:35 -0500 From: "John R. Jackson" Content-Type: text Content-Length: 5630 Status: OR Never one to leave a perfectly good script alone :-), I've tweaked your "atchange" and "eh" scripts a bit. The "eh" script didn't work right as pulled off the web page. I suspect the "kill 0" at the end was supposed to be "kill %0". Even so, we had some other problems (perl4 vs perl5) that were causing "atchange" to fail, which in turn caused "eh" to misbehave, so I changed it to save the pid, make sure "atchange" stayed running, then kill it explicitly on exit. As long as I was in the neighborhood :-), I also set it up to start netscape if there didn't appear to be one running. Yes, there are some us old timers out here who do not have netscape permanently on the desktop :-). --- /tmp/eh Fri Jul 25 11:40:36 1997 +++ bin/eh Fri Jul 25 12:30:30 1997 @@ -12,11 +12,11 @@ # - fix the shebang line and the PATH # - make sure atchange is installed PATH=/usr/local/bin:/usr/local/bin:/bin:/usr/bin:/home/kaylor/toms/script +ARGV0=${0##*/} # print usage message and exit usage() { - ARGV0=${0##*/} echo "usage: $ARGV0 [-l] filename|filename.html" 1>&2 test "$1" = "long" || exit 0 @@ -88,10 +86,27 @@ test -f $html || html_template > $html -netscape -noraise -remote "openFile($html)" +if netscape -noraise -remote "openFile($html)" +then + : +else + netscape $html & +fi + atchange $html "netscape -noraise -remote 'reload'" & +pid=$! + +# make sure atchange stays running +sleep 1 +if kill -0 $pid > /dev/null 2>&1 +then + : +else + echo "$ARGV0: atchange failed" + exit 1 +fi # finally, invoke the editor: ${EDITOR:-vi} $html -kill 0 -wait +kill $pid +wait $pid On the "atchange" front are the following: * When using "atchange", I find myself constantly changing things in the "automate" script (e.g. adding new html files). This version of "atchange" treats a command script like any other file when looking for changes, and if it is altered, "atchange" restarts itself. * Added a "-t" option to control the sleep time. If many other options are added, one of the getopt() routines should be used for argument parsing. Since I just added one, I kept it simple. * Made the script work with either perl4 or perl5. * Used "-w" to catch questionable code. Fixed a few odds and ends as a result. * Closed the command file when done. * Skipped files that do not exist. * Used select() in the "wait for idle" loop. Enjoy, and thanks for the new tool. John R. Jackson, Technical Software Specialist, jrj@purdue.edu #!/usr/local/bin/perl -w # by Jeff Haemer # and a tip o' the hat to Tom Schneider # who wrote the original version as a shell script # version = 2.03 of atchange 1997 Jan 9 # delay time is 0.25 seconds # For current version and other information about this program, see: # https://alum.mit.edu/www/toms/atchange.html # Tom Schneider # toms@alum.mit.edu # https://alum.mit.edu/www/toms/ $save_cmd = $0; # save the command name @save_args = @ARGV; # and the argument list $0 =~ s(.*/)(); # basename $usage = "usage: $0 [-t sleeptime] filename cmd\n"; $usage .= " $0 [-t sleeptime] command_file\n"; @ARGV || die $usage; # check for proper invocation $sleeptime = 0.25; # default is to check every 0.25 seconds if ($ARGV[0] =~ /^-t([.\d]+)$/) { # e.g. "-t2.5" or "-t5" $sleeptime = $1; # set a new sleep time shift; # skip this argument } elsif ($ARGV[0] eq "-t" && $#ARGV > 0 && $ARGV[1] =~ /^[.\d]+$/) { # e.g. "-t 2.5" or "-t 5" $sleeptime = $ARGV[1]; # set a new sleep time shift; # skip the "-t" shift; # skip the sleep time } @ARGV || die $usage; # check for proper invocation $shell = $ENV{"SHELL"} ? $ENV{"SHELL"} : "/bin/sh"; open(SHELL, "|$shell") || die "Can't pipe to $shell: $!"; select(SHELL); $| = 1; if (@ARGV > 1) { # it's a file and a command $file = shift; # peel off the filename $cmd{$file} = join(" ", @ARGV) . "\n"; # and the command $old{$file} = (stat($file))[9]; # mod time. } else { # it's a program $cmd{$ARGV[0]} = ""; $old{$ARGV[0]} = (stat($ARGV[0]))[9]; # mod time. open(PGM, $ARGV[0]) || die "Can't open $ARGV[0]: $!"; $/ = ""; # paragraph mode while() { # first read the program s/#.*\n/\n/g; ($file, $cmd) = /(\S*)\s+([^\000]+)/; if ($file) { if (! $cmd) { warn "file without command"; } else { $cmd{$file} = $cmd; $old{$file} = (stat($file))[9]; # mod time. } } elsif ($cmd) { print $cmd; # shell command as-is } } close(PGM); } while(1) { # The following "select" call pauses for some period of time, # then falls through. select(undef, undef, undef, $sleeptime); foreach (keys %cmd) { # rip through the whole list if (&atchange($_) && @ARGV <= 1 && $_ eq $ARGV[0]) { close(SHELL); # the script changed, re-exec ourself exec $save_cmd, @save_args; } } } sub atchange { # if $file has changed, do $cmd{$file} local($file) = @_; local($new); return 0 unless (-e $file); # test for existance $new = (stat(_))[9]; # use -e stat result for mod time return 0 if (defined ($old{$file}) && $old{$file} == $new); while (1) { # wait until it stops changing $old{$file} = $new; # We want to wait a little longer than one second because # that is the resolution of the modification time. select(undef, undef, undef, 1.1); return 0 unless (-e $file); # test for existance $new = (stat(_))[9]; # use -e result for mod time last if ($old{$file} == $new); # file has gone idle } print $cmd{$file}; return 1; } exit (0);