Re: What conditions cause the -e file test to return false

One I thought would trip it up is doing a chmod 000 on a file owned by root and testing it existed using a non-root user. Nope, you still get the -e returning true. (Which does seem to be the desired semantics, since the file does exist.

Update: Ahh, here's a case. If the user running the script cannot cd into the directory containing the file, then -e fails.

Comment on Re: What conditions cause the -e file test to return false

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Re^2: What conditions cause the -e file test to return false by ikegami (Patriarch) on Feb 27, 2009 at 16:23 UTC
Do `chmod 000` on the directory containing the file and it won't be found for non-root users. $ perl -MErrno=ENOENT -le' $found = -e shift; die("stat: $!\n") if !defined($found) && $! != ENOENT; print($found ? "found" : "not found"); ' foo/bar not found $ touch foo/bar $ perl -MErrno=ENOENT -le' $found = -e shift; die("stat: $!\n") if !defined($found) && $! != ENOENT; print($found ? "found" : "not found"); ' foo/bar found $ chmod a-x foo $ perl -MErrno=ENOENT -le' $found = -e shift; die("stat: $!\n") if !defined($found) && $! != ENOENT; print($found ? "found" : "not found"); ' foo/bar stat: Permission denied [download]	[reply] [d/l] [select]

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Re^2: What conditions cause the -e file test to return false
by ikegami (Patriarch) on Feb 27, 2009 at 16:23 UTC

chmod 000

$ perl -MErrno=ENOENT -le'
   $found = -e shift;
   die("stat: $!\n") if !defined($found) && $! != ENOENT;
   print($found ? "found" : "not found");
' foo/bar
not found

$ touch foo/bar

$ perl -MErrno=ENOENT -le'
   $found = -e shift;
   die("stat: $!\n") if !defined($found) && $! != ENOENT;
   print($found ? "found" : "not found");
' foo/bar
found

$ chmod a-x foo

$ perl -MErrno=ENOENT -le'
   $found = -e shift;
   die("stat: $!\n") if !defined($found) && $! != ENOENT;
   print($found ? "found" : "not found");
' foo/bar
stat: Permission denied
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