PLOD(1) PLOD PLOD(1)
2 February 1993
NAME
plod - keep a log of your work
SYNOPSIS
plod [ -s ] [ -f file ] [ one line message ]
plod [ -s ] [ -f file ] -C|-E|-P|-V [ logfile [ key ]]
plod [ -s ] [ -f file ] -g|-G pattern [ logfile [ key ]]
DESCRIPTION
PLOD is a tool developed to help System/Network Administrators (and
others) keep track of the work that they do. Good logs are useful
both as a personal reference and to show to your management on a
regular basis or around performance review time. By default, logs will
be stored in an encrypted format in the directory $HOME/.logdir, but
this behavior is completely customizable (see ENVIRONMENT and
CUSTOMIZATION below).
The first form of the command will enter a short message on the
command line into your log file. If no message is present on the
command line, a date/time stamp will be printed and PLOD will go into
an interactive mode reminiscent of BSD mail. Many tilde escape
sequences are supported (see COMMANDS below or type ~h or ~? within
interactive mode). Enter a period on a line by itself to end your log
entry.
The second mode allows you to review or edit your old log files. The
-P option invokes the default PAGER defined in the PLOD source, or as
defined in your environment, on the current log file. The -E and -V
flags invoke EDITOR and VISUAL respectively. The -C option will
simply dump the current log file to the standard output. This is
useful for piping your log file to other commands, such as lpr. Older
log files may be accessed by specifying a file name and optional
encryption key on the command line.
The third mode allows you to search your logs for a particular
pattern. The -g flag specifies a case-insensitive match, while -G
does a case sensitive search. The pattern may be any valid Perl
regular expression. Don't forget to quote the pattern to protect any
special characters from the shell.
In any mode, the -f flag allows the user to specify a different
startup file than the default ($HOME/.plodrc). The -s flag tells PLOD
to prompt the user for their encryption key. When making a one-line
log entry, the -f and -s options must appear first on the command
line.
ENVIRONMENT
PLOD supports a number of variables which can be modified to customize
its behavior. The values of these variables may be changed by editing
PLOD directly, by assignment in a system-wide startup file, by
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creating an environment variable, or by assignment in the user's
startup file (see CUSTOMIZATION below). PLOD recognizes the following
environment variables:
SEPARATOR
A string used to separate one entry from another in the log file.
This string must be constant throughout the entire file or the -g
and -G command line options will not work correctly. Default is
----- (five dashes).
STAMP
The time/date stamp entered into every log entry. Set this to
null if you do not wish to datestamp your logs. Default is
MM/DD/YY, HH:MM --.
PREFIX
String to be prepended to each line of log entry as it goes into
your log file. Default is the empty string.
SUFFIX
String to be appended to each line of log entry as it goes into
your log file. Default is the empty string.
EDITOR
The user's preferred editor (used by the -E command line flag and
the ~e, ~E, and ~M escape sequences). Default is
/usr/local/bin/emacs.
VISUAL
The user's preferred visual editor (used by -V, ~v, and ~V).
Default is /usr/local/bin/emacs.
PAGER
The user's preferred pager (used by -P, ~p, and ~P). Default is
/usr/local/bin/less.
LINES
The number of lines on the current display. Used to determine
when the PAGER needs to be invoked. Default is 24.
CRYPTCMD
The encryption command to be used. If you do not wish to encrypt
your log files, set this to null. Default is /bin/crypt (the
standard UNIX crypt command is not in the least secure, but does
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provide protection from casual browsing).
KEYVAL
The key to be used with CRYPTCMD. Default is pl<yr><mn>od.
PROMPT
Setting this variable to true (non-zero) causes PLOD to prompt the
user for their encryption key rather than using KEYVAL. This is
equivalent to using the -s flag on the command line. Default is
false (zero).
LOGDIR
Where log files are placed. Default is $HOME/.logdir.
LOGFILE
The name of the current log file. LOGDIR will be prepended to
this value if LOGFILE is not an absolute path. Default is
<yr><mn>.
HOME
The user's home directory. Default taken from user's password
entry.
PLODRC
The name of the user's startup file. Can also be set with the -f
command line switch. Obviously, there isn't a lot of point in
trying to set this in your .plodrc file. HOME will be prepended
to this value of PLODRC is not an absolute path. Default is
.plodrc.
BACKUP
The current LOGFILE is copied to BACKUP as the program begins
execution. If, when the program terminates, the LOGFILE is gone
or zero-length, then it is replaced the the BACKUP copy and the
current log entry is dumped to DEADLOG. Setting BACKUP to null
disables this feature. The value of HOME is prepended if BACKUP
is not an absolute path. Default is .plod<pid>.bak.
DEADLOG
Where interrupted log entries are placed. HOME will be prepended
to this value if DEADLOG is not an absolute path. Default is
dead.log.
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TMPFILE
Scratch file used throughout execution of program. Default is
/tmp/plodtmp<pid>.
COMMANDS
Many tilde escape sequences are supported under PLOD's interactive
mode. Users may also define their own escape sequences in PLOD's
initialization file (see CUSTOMIZATION below). Currently defined
sequences are:
~h, ~? Show a list of all escape sequences with a short usage
message.
~= var[, ...]
Display the current value of one or more variables.
~e Edit the current buffer with $EDITOR.
~v Edit the current buffer with $VISUAL.
~p Display the contents of the current buffer (using $PAGER if
necessary).
~V [ logfile [ key ]]
Call $VISUAL on the current log file, or on some other log
file as specified. An additional encryption key may also be
supplied.
~E, ~l [ logfile [ key ]]
Similar to ~E except that $EDITOR is used.
~P, ~L [ logfile [ key ]]
Same as ~E and ~V except that $PAGER is invoked.
~q Quit PLOD, saving contents of buffer into $DEADLOG.
~x Quit without attempting to save buffer.
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~d Append contents of $DEADLOG to current buffer.
~r somefile
Append contents of file to current buffer.
~a somefile
Append contents of current buffer to file.
~w somefile
Overwrite file with contents of current buffer.
~X Perl-code
Execute a line of Perl code.
~M Invoke $EDITOR and execute resulting file as Perl code. Each
successive invocation of this escape will edit the previously
executed Perl code so as to make it easier to go back and
correct small errors.
~! command
Execute a command in the shell and return.
~> command
Append the output of a command to the current buffer.
~| command
Pipe the current buffer through a command and replace the
buffer with the resulting output.
CUSTOMIZATION
Like most UNIX utilities, PLOD has an initialization file, the
.plodrc, which is read at startup. Unlike most UNIX utilities, this
file is interpreted as Perl code. Thus, if you wished to assign a new
value to a customization variable you would use the syntax
$LOGDIR = "$HOME/mylogs";
The location of the user startup file may changed with the -f command
line switch or by setting the PLODRC environment variable.
PLOD also looks for a system-wide customization file, /etc/plodrc.
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The order of evaluation is: hard coded defaults in PLOD, then the
/etc/plodrc file, then the user's environment, and finally the user's
PLODRC file.
Beyond simple variable customization, the PLODRC file can be used as
an automatic pre-execution block and to define subroutines that will
be used during the execution of the program. For example, PLOD will
attempt to execute user-defined &on_exit() or &on_error() routines (if
they are defined) when the program terminates, depending upon whether
the program exits normally or abnormally.
Another application of this feature is to change the encryption scheme
used by PLOD to use some alternate (more secure) encryption mechanism.
Encryption and decryption in PLOD are done via &encrypt() and
&decrypt() routines. Both routines accept the same three arguments:
a key value, an input file (either encrypted or decrypted depending
upon which routine is being called), and an output file to place the
result into. The routines must return non-zero upon success and zero
on failure, and should prompt the user for an encryption key if PROMPT
is set. As an example, here are the default &encrypt() and &decrypt()
routines from the PLOD source:
sub encrypt {
local($key, $inputfl, $outputfl) = @_;
local($safekey, $safeinp, $safeout);
unlink($outputfl);
if ($PROMPT) { # Prompt for $KEYVAL if $PROMPT has been set
print "File is $file.0;
print "Please enter encryption key: ";
system 'stty', '-echo';
chop($key = <STDIN>);
system 'stty', 'echo';
print "0;
}
($safekey = $key) =~ s/(W)/\$1/g;
($safeinp = $inputfl) =~ s/(W)/\$1/g;
($safeout = $outputfl) =~ s/(W)/\$1/g;
!(system("$CRYPTCMD $safekey < $safeinp >$safeout") >> 8);
}
sub decrypt {
local($key, $inputfl, $outputfl) = @_;
local($safekey, $safeinp, $safeout);
unlink($outputfl);
if ($PROMPT) { # Prompt for $KEYVAL if $PROMPT has been set
print "File is $file.0;
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print "Please enter encryption key: ";
system 'stty', '-echo';
chop($key = <STDIN>);
system 'stty', 'echo';
print "0;
}
($safekey = $key) =~ s/(W)/\$1/g;
($safeinp = $inputfl) =~ s/(W)/\$1/g;
($safeout = $outputfl) =~ s/(W)/\$1/g;
!(system("$CRYPTCMD $safekey < $safeinp >$safeout") >> 8);
}
Note that any possible meta characters in the key or in filenames are
protected from the shell with backslashes before they are passed to
system(). An &encrypt() or &decrypt() routine defined in the PLODRC
will supercede the default definitions in the PLOD source.
It is also possible for the user to create their own tilde escapes.
First, create a subroutine which performs the desired function. Then
assign the type glob which references that function to global array
%funcs indexed by the character of the escape sequence. Any arguments
that the user enters after the tilde escape will be passed into the
function as a single string in @_. The list @lines contains the
current buffer.
As an example, here is the append to file function (~a) from the PLOD
source:
sub appendfl {
local($file) = @_;
if (!open(OUTP, ">> $file")) {
warn "*** Could not append to file $file\n";
return;
}
print OUTP @lines;
close(OUTP);
print "Wrote ", scalar(@lines), " lines to file $file\n";
print "(continue composing note)\n";
}
$appendfl = "file\t\tAppend contents of buffer to file";
$funcs{'a'} = *appendfl;
The scalar variable $appendfl is used by PLOD's help function (~h or
~?) to provide a descriptive message about the escape sequence. As a
further example, here is PLOD's help function
sub helpuser {
local($safename);
$long = (scalar(keys %funcs) >= $LINES) && open(TMP, ">$TMPFILE");
for (sort keys %funcs) {
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*info = $funcs{$_};
if ($long) {
print TMP "~$_ $info0;
}
else { print "~$_ $info0; }
}
if ($long) {
close(TMP);
($safename = $TMPFILE) =~ s/(W)/\$1/g;
system("$PAGER $safename");
unlink $TMPFILE;
}
}
$helpuser = "Print this message";
$funcs{'h'} = *helpuser;
$funcs{'?'} = *helpuser;
Note the use of various customization variables as well as the
assignment of the type glob to two different indices of the %funcs
array. Note also that again we protect any meta characters from the
shell.
Note that it is considered good form to return() from user defined
subroutines rather than terminating PLOD prematurely. If you must
abort execution from within a routine, it is recommended that you call
&PLODNormExit() or &PLODBadExit() so that you get both the BACKUP
mechanism and the appropriate &on_exit() or &on_error() call.
FILES
$HOME/.plodrc Default location for users' personal
initialization files
/etc/plodrc System-wide initialization file
Various other customizable file locations.
SEE ALSO
perl(1)
AUTHORS
The original idea for PLOD comes from Bill Mendyka (mendyka@dg-
rtp.dg.com).
The current Perl implementation was developed by Hal Pomeranz
(pomeranz@aqm.com).
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An Emacs mode for PLOD was developed by Paul Foley (paul@ascent.com),
and another by Paul Hudson (paulh@harlequin.com).
Additional improvements have been suggested/developed by: Bobby
Billingsley (bobby@dc.dk), David W Crabb
(crabb@phoenix.Princeton.EDU), Michel Dignard
(dignard@ERE.UMontreal.CA), John Ellis (ellis@rtsg.mot.com), Bob
Gibson (rjg@sco.COM), Mike Lachowski (mlachow@erenj.com), Eric
Prestemon (ecprest@pocorvares.er.usgs.GOV), Erik E. Rantapaa
(rantapaa@math.umn.edu), Scot Schneebeli (sls@tct.com), James Tizard
(james@ringo.ssn.flinders.edu.au), and G. Paul Ziemba
(paul@alantec.com).
BUGS
Any bug reports or suggestions for improvement should be submitted to
Hal Pomeranz via email at pomeranz@aqm.com.
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