perl 的一些默认变量

时间：2010-02-25 来源：PHP爱好者

Predefined Variables	Perl provides a large number of predefined variables. The following is a list of some common predefined variables:
	$_	The default input and pattern-searching space.
	$.	Current line number for the last filehandle accessed.
	$@	The Perl syntax error message from the last eval() operator.
	$!	Yields the current value of the error message, used with die.
	$0	Contains the name of the program being executed.
	$$	The process number of the Perl running this script.
	$PERL_VERSION / $^V	The revision, version, and subversion of the Perl interpreter.
	@ARGV	Contains the command-line arguments.
	ARGV	A special filehandle that iterates over command-line filenames in @ARGV.
	@INC	Search path for libarary files.
	@_	Within a subroutine the array @_ contains the parameters passed to that subroutine.
	%ENV	The hash %ENV contains your current environment.
	%SIG	The hash %SIG contains signal handlers for signals.