If you wanted to do:

dosomething.pl myfile.txt

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You need to get the filename from the first element in @ARGV, the arguments array. You may also want to check out Multiple STDIN sources.

No. <> treats as a list of file names, and opens each of them in turn. <> only reads from STDIN if @ARGV is empty. In other words,

while (<>) {
  # do something with $_
}

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works for all of the following:

cat myfile.txt | dosomething.pl

dosomething.pl < myfile.txt

dosomething.pl myfile.txt

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In reply to Re^2: How to accept ARG from PIPE or STDIN? by ikegami
in thread How to accept ARG from PIPE or STDIN? by monkfan

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