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Perl Language Reference Manual
by Larry Wall and others
Paperback (6"x9"), 724 pages
ISBN 9781906966027
RRP £29.95 ($39.95)

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exit EXPR

exit

Evaluates EXPR and exits immediately with that value. Example:

$ans = <STDIN>;
exit 0 if $ans =~ /^[Xx]/;

See also die. If EXPR is omitted, exits with 0 status. The only universally recognized values for EXPR are 0 for success and 1 for error; other values are subject to interpretation depending on the environment in which the Perl program is running. For example, exiting 69 (EX_UNAVAILABLE) from a sendmail incoming-mail filter will cause the mailer to return the item undelivered, but that's not true everywhere.

Don't use exit to abort a subroutine if there's any chance that someone might want to trap whatever error happened. Use die instead, which can be trapped by an eval.

The exit() function does not always exit immediately. It calls any defined END routines first, but these END routines may not themselves abort the exit. Likewise any object destructors that need to be called are called before the real exit. If this is a problem, you can call POSIX:_exit($status) to avoid END and destructor processing. See "Perl modules (packages and symbol tables)" (perlmod) in the Perl Library Reference Manual (Volume 2) for details.

ISBN 9781906966027Perl Language Reference ManualSee the print edition