Using the if statement to check the command line parameters : Special Variables « Language Basics « Perl






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  2. Language Basics
  3. Special Variables

Using the if statement to check the command line parameters

   


#!/usr/bin/perl -w

use strict;

sub version {
    print "version\n";
}

my $option = shift;    # defaults to shifting @ARGV

version() if $option eq "-v" or $option eq "--version";

print "Hello, world.\n";








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39.$MATCH = $&
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41.$SIG{__WARN__} = 'IGNORE';
42.$SIG{__WARN__} = sub {die "Warning: $_[0]"};
43.$\ is 'END_OF_OUTPUT'
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45.$^O stores the name of the operating system
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48.$^X: get the Perl execuatable file name
49.$_ for print function
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