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  • $&

    String matched by last pattern match.

    $`

    String preceding what was matched in last pattern match.

    $'

    String following what was matched in last pattern match.

    $_

    Default input and pattern-searching space.

    $.

    Current line number on the filehandle last read.

    $/

    Input record separator, newline by default. You can set this to an entire file by "local $/".

    $\

    The output record separator for the print operator. You can set this to "\n" instead of adding that to every print statement.

    $,

    The output field separator for the print operator.

    $"

    The output field separator for the print operator when array is enclosed in double quotes, i.e. "@animals".

    $$

    PID of this perl script.

    $?

    Status returned by system command or `` command.

    $0

    Contains name of perl script.

    $!

    Current value of errno.

    %ENV

    System environment variables

    @ARGV

    Args passed into perl program.

    @_

    Args passed to subroutine.

    $1,$2

    Subpatterns extracted from regular expressions.

    $@

    Perl syntax error trapped by eval

    Version

    $^V

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