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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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-%s on unopened filehandle %s

(W unopened) You tried to invoke a file test operator on a filehandle that isn't open. Check your control flow. See also .

ISBN 9781906966027Perl Language Reference ManualSee the print edition