Alright, there may be a very simple answer to this question that I have missed, but here goes...

I'm writing a perl script that needs to provide a number of different interfaces (e-mail wrapper, CGI, and command line namely). What I need to know is how the script was run. Was it called as an e-mail wrapper, CGI script, from the command line?

I know that I can check on the existance of certain %ENV keys, but I'm not certain how portable or reliable some of those are. Is $ENV{LOGNAME} only set for e-mail wrappers running under Linux with sendmail? Will that same one exist on SunOS running Postfix? Questions like these trouble me, and I cannot answer them.

Is there a better way than checking %ENV and hoping that these are reliable on 'x' OS with 'y' mail server or 'z' web server? ;-)

(Also, before someone suggests it, I know I can just have the bulk of the code in an external module and then have small script-shells that are specific for each interface. I'm just trying to avoid that because I ultimately don't know what interfaces I will finally choose on using for this particular script)

In reply to How was my script ran? by criswell

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