Hi people,

Another STDIN-related question. (I think. :/)

I'm refactoring an app that analyses email messages. I'd like to set up a conditional at the beginning of the script where I can take piped in data if it's available, and do something else if it's not (in this case, go look in an IMAP folder.) In other words, I'd like to be able to call...

./script.pl

...and have my script do its default behavior (use IMAP), or pipe it a message directly...

cat sample.eml | ./script.pl
or
./script.pl < sample.eml

and just deal with sample.eml.

When groping for a handle on understanding the mechanism I need, I simply tried doing this: 
if ( <STDIN> ) {
    print "Got STDIN.\n";
    # Look for more STDIN till there's no more.
} else {
    print "Default behavior.\n";
    # Go connect to the IMAP server and feed there.
}

[download]
Of course, when I execute, my script sits there and waits for STDIN. One of those moments where my stupidity becomes painfully obvious to me only after the fact. But I don't know which way to go with this, and I don't know how to search for the answer.

All I know is that I want this program to take what gets offered it, and if nothing is offered, to go do its own thing without sitting around and waiting for a handout.

Any /(help|nudges in the right direction)/ will be much appreciated.

In reply to Piping input as an option by jkelly

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