Re: How was my script ran?

How about testing if STDIN is a tty - if yes, the script is run from the command line. If not, it's a CGI or the e-mail wrapper. CGI sets several HTTP_* variables, check one of these. If set, it's CGI. If not, e-mail wrapper.

# Note - not very thoroughly tested
if (-t STDIN) {
    # command-line
} elsif (defined $ENV{SERVER_NAME}) {
    # CGI - I used SERVER_NAME, as it _should_ be set
} else {
    # e-mail
}
[download]

Now I can't guarantee how portable this is, as I didn't test the e-mail part at all - and I can only test Win2K and FreeBSD. Good luck!

Comment on Re: How was my script ran? Download Code

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Re^2: How was my script ran? by LAI (Hermit) on Mar 05, 2003 at 15:33 UTC
That's a good idea, but if the script is being called by cron or at (or Windows Scheduled Event :o), will STDIN be a tty? I have no idea, come to think of it, as what STDIN would be identifiable in that circumstance. Or is the point moot -- will this script never be automated? LAI :eof	[reply]
Re: Re^2: How was my script ran? by jsprat (Curate) on Mar 05, 2003 at 17:57 UTC
Yeah, I thought of that too. Another one - if the script gets its input via a pipe, the -t will return false. I'm sure there are more scenarios that we haven't thought of yet. BTW, windows actually starts a shell for a perl script, so -t returns true. On FreeBSD (and other *nix, I'm sure), -t returns false for a cron job.	[reply]