Filename of parent script available?

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Greetings from a lowly altar boy,

I have been asked by my manager to write a number of database querying, timestamping, and error reporting scripts and modules.

I have an email script that generates an email with a timestamp and I would like it to report who called the script. Something similar to $0 but for the parent script. I'm quite new to Perl so I don't know all the technical terms.

For example the call would be:

#args(script to be called, subject, message body)
my @args = ('sendmail.pl', 'An error has occurred!', Error!');

system(@args) == 0 or die "system @args failed: $?";
[download]

And then I would like sendmail.pl to know which script called it without passing additional arguments. Is this possible?

Right now sendmail.pl is just a script but would converting it into a module make things easier (obviously renaming it in the process)? All it does is take arguments and shoots out an email.

Thanks a ton.

Greg

Comment on Filename of parent script available? Download Code

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Re: Filename of parent script available? by Fletch (Bishop) on Jul 15, 2005 at 15:43 UTC
There's nothing off the shelf, but you could always use `getppid` and one of the `ps`-ish modules (Proc::ProcessTable or GTop for example) to find it out. Update: of course with the caveat that if the OS allows it the process name may have been changed; or someone nefarious could use symlinks and an intermediary `exec` even if it doesn't. -- We're looking for people in ATL	[reply] [d/l] [select]
Re^2: Filename of parent script available? by Anonymous Monk on Jul 15, 2005 at 15:51 UTC
Hmmm... Seems like the easiest thing is to just pass $0 as the first argument. Thanks for the tip though, I will have to check those out when I have more time. Greg	[reply]
Re: Filename of parent script available? by izut (Chaplain) on Jul 15, 2005 at 16:52 UTC
You can also use %ENV to send/retrieve information to the child script (example follows) script1.pl `#!/usr/bin/env perl # script1.pl $ENV{'MY_NAME'} = 'script1'; print system('./script2.pl', 'arg'), "\n";` [download] script2.pl `#!/usr/bin/env perl # script2.pl print $ENV{'MY_NAME'}, "\n";` [download] surrender to perl. your code, your rules.	[reply] [d/l] [select]
Re: Filename of parent script available? by radiantmatrix (Parson) on Jul 15, 2005 at 17:23 UTC
You could "sorta" modularize your `sendmail.pl`. Wrap the main logic of that script into a function (say, `sendmail_main()`), and add a line like this at the top of that function: `my @ARGV = @_;` [download] Then, in your calling script, you can: `require 'sendmail.pl'; sendmail_main(@args);` [download] Inside of Sendmail, you can use caller to discover the name of the calling file. I highly suggest, however, that you fully modularize your script; you could always use create a new `sendmail.pl` that did something like: `use Sendmail; Sendmail::send_mail(@ARGV);` [download] if you still need to call the script separately. <-radiant.matrix-> Larry Wall is Yoda: there is no `try{}` (ok, except in Perl6; way to ruin a joke, Larry! ;P) The Code that can be seen is not the true Code	[reply] [d/l] [select]