The %SIG hash sets signal handlers for signals. : Special Variables « Language Basics « Perl

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Perl » Language Basics » Special Variables

The %SIG hash sets signal handlers for signals.


    



The %SIG array contains values only for signals set within the Perl script.



#!/usr/bin/perl

sub handler{

     local($sig) = @_;  # First argument is signal name

     print "Caught SIG$sig -- shutting down\n";

     exit(0);

}

$SIG{'INT'} = 'handler';  # Catch <Ctrl>-c

print "Here I am!\n";

sleep(10);

$SIG{'INT'}='DEFAULT';

$SIG{'INT'}='IGNORE';

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4.	The list separator is a comma
5.	The list separator is the empty string
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21.	Assign value to @_
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31.	Error message is stored in $!
32.	Extracts information from the $] variable.
33.	$! is the error number
34.	$! stores the error message
35.	$" is the separator
36.	$# is the default format
37.	$(dollar), is the separator
38.	$MATCH = $&
39.	$SIG{__DIE__}
40.	$SIG{__WARN__} = 'IGNORE';
41.	$SIG{__WARN__} = sub {die "Warning: $_[0]"};
42.	$\ is 'END_OF_OUTPUT'
43.	$^ is the format header
44.	$^O stores the name of the operating system
45.	$^S: is inside eval
46.	$^W: Check the '-w switch'
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58.	List all command line argument
59.	Local builtin var
60.	Locate all numbers less than 6
61.	Manipuate @_ and return @_
62.	Mannually change the $1 variable
63.	Match: $&
64.	Perl 5 Built-In Variables
65.	Perl's modules reside in the directories named in the @INC array, or subdirectories
66.	Perl's special arrays
67.	Perl's special variables
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76.	Resetting array base
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81.	System variables that control how write sends output to a file
82.	Test of open and die with $!.
83.	The $_ Scalar Variable
84.	The @* field
85.	The @ISA Array and Calling Methods
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