July 2002
Beginner to intermediate
96 pages
1h 53m
English
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Chapter 38. Special Hashes
%!Requires the
Errnomodule. Each element of%!has a nonzero value only if$!is set to that value.%ENVContains the current environment. The key is the name of an environment variable; the value is its current setting.
%EXPORT_TAGSDefines names for sets of symbols. Used by the
Exportermodule.%INCContains the list of files that have been included with use, require, or do. The key is the filename as specified with the command; the value is the location of the file.
%SIGRegisters signal handlers for various signals. The key is the name of the signal (without the
SIGprefix); the value a subroutine that is executed when the signal occurs.__WARN__and__DIE__are pseudo-signals to attach handlers to Perl warnings and exceptions.
perlvar.
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