Hi everyone, I'm trying to handle the possibility that a script executes based on following scenarios 1> no arguments are passed to the script 2> arguments maybe passed from command line 3> piped data is passed to a Perl script from file. 
if ($#ARGV == -1){..#no arguments passed.}
elsif ($#ARGV == 1){..# arguments passed from command line.} 
elsif (-t STDIN and not @ARGV){..#piped inputs are supplied....do this
+}
else {default: usage error}

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The first two scenarios works fine.The piped input scenario works good if i just use it as a seperate perl script nd do test.pl < input.txt But when i try to combine it with above two scenarios it always enters the first case. I read somewhere that -t option is used to check if handle is open to tty and since piped inputs are supplied through stdin i thought this works but somehow it doesnt. I also tried using (*stdin) in the third case but it messes up the other two options ..Any sugestions ? - Thanks Ram

In reply to Using PIped-in and invocation arguments in same script by justkar4u

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