zjunior has a pretty good idea about doing it (GATEWAY_INTERFACE will be defined if the script is run through a web-server), but what if some joker sets GATEWAY_INTERFACE to bash in his .bashrc? (stupid I know, but it's been known to happen ;), well from perlfaq8 
How do I find out if I'm running interactively or not?

Good question. Sometimes -t STDIN and -t STDOUT can give clues, someti
+mes not.

if (-t STDIN && -t STDOUT) {
        print "Now what? ";
    }

[download]
-t tells you if a filehandle is tied to a tty. Now I don't know what happens during forking and the like, but the above usually works ;)

 
______crazyinsomniac_____________________________
Of all the things I've lost, I miss my mind the most.
perl -e "$q=$_;map({chr unpack qq;H*;,$_}split(q;;,q*H*));print;$q/$q;"

In reply to (crazyinsomniac) Re: Outputting to browser vs DOS...how can you tell? by crazyinsomniac
in thread Outputting to browser vs DOS...how can you tell? by S_Shrum

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