Pass command line arguments as well as input from STDIN for Perl script?

perl stdin command-line-arguments argv
naveenhegde picture naveenhegde · Mar 25, 2011 · Viewed 15.3k times · Source

I have a Perl script which takes both command line arguments and STDIN

#!/usr/bin/perl -w
use strict;
use warnings;

my $logpath = $ARGV[0];
print "logpath : $logpath\n";

print "Name : ";
my $name = <>;
chomp($name);
print "my name is $name\n";

It does not stop at stdin input. Works fine for any one of command line or standard input but not for both.

Any Reason?

Answer

codaddict picture codaddict · Mar 25, 2011

Change

my $name = <>;

to

my $name = <STDIN>;

If @ARGV has no elements, then the diamond operator will read from STDIN but in your case since you are passing arguments though command line, @ARGV will not be empty. So when you use the diamond operator <> to read the name, the first line from the file whose name is specified on the command line will be read.

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