Errno - System errno constants
use Errno qw(EINTR EIO :POSIX);
Errno
defines and conditionally exports all the error constants defined in your systemerrno.h
include file. It has a single export tag,:POSIX
, which will export all POSIX defined error numbers.
Errno
also makes%!
magic such that each element of%!
has a non-zero value only if$!
is set to that value. For example:
use Errno;unless (open(FH, "/fangorn/spouse")) { if ($!{ENOENT}) { warn "Get a wife!\n"; } else { warn "This path is barred: $!"; } }
If a specified constantEFOO
does not exist on the system,$!{EFOO}
returns""
. You may useexists $!{EFOO}
to check whether the constant is available on the system.
Importing a particular constant may not be very portable, because the import will fail on platforms that do not have that constant. A more portable way to set$!
to a valid value is to use:
if (exists &Errno::EFOO) { $! = &Errno::EFOO;}
Graham Barr <gbarr@pobox.com>
Copyright (c) 1997-8 Graham Barr. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
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