http://www.perlmonks.org?node_id=575555


in reply to Re: bsd_glob does not reset $! (The lessons learned)
in thread bsd_glob does not reset $!

For performance and sanity my routine will first do a test for file-existance and then try to glob it. It feels clumsy, though.

You need to check for file-existance afterwards, not beforehand. glob is not guaranteed to produce a list of existing files. For example, glob('file{a,b}') will return filea and fileb whether either, neither or both exists.

@list = bsd_glob('~gnat', GLOB_ERR); die("Unable to glob: $!\n") if GLOB_ERROR; # Keep only references to existing files. @list = grep -f, @list; die("glob returned no existing results\n") if not @list;

I am still confused about the way $! behaves in this case

This case is not special.

# XXX WRONG $rv = print $fh (...); if ($!) { die("Unable to write to file: $!\n") } # Ok $rv = print $fh (...); if ($rv) { die("Unable to write to file: $!\n") }