Re: stat() and tilde prefix (was bad bash tab completion)

[Thomas Wolff <towo@towo.net>]

Am 07.02.2013 16:30, schrieb Eric Blake:
> ...
>
> ...
> the fact that cygwin's handling of .. is not POSIX-compliant.  I think a
> better fix would be to change file_exists() itself instead of adding a
> misnamed wrapper function; then bashline.c wouldn't even need patching.
>   The string 'tilde' need not even be in the patch; what you are really
> after is a function that says that if '..' is found within a string
> being probed for existence, then add an additional check to see if the
> prefix of that string exists as a directory.
>
> But I don't mind experimenting with the idea - it remains to be seen
> whether people will complain that bash is noticeably slower because it
> takes time to double-check instead of rely on cygwin's non-POSIX
> shortcut.  And the slowdown would only be on paths containing a '..'; I
> would NOT be checking for symlinks (even though symlinks containing ..
> are also being interpreted in a non-POSIX manner, it is much more
> expensive to second-guess if you have to check every name for being a
> symlink than it is to just check for literal ..).
Do I interpret correctly that you talk about bash filename completion here?
Referring to http://cygwin.com/ml/cygwin/2013-01/msg00201.html,
I'd like to point out that while this ".." thing is a cygwin bug, or 
known downside as Corinna says,
the same issue occurs on Linux precisely with filename completion which 
isn't consistent there either.
So it would be "over-fixing" to handle that specifically in bash.

On the other hand, considering again this "downside":
If the core cygwin filesystem function would follow this approach,
simply checking for an occurrence of ".." first before resolving the 
filename,
wouldn't that be an acceptable fix without inappropriate penalty?

------
Thomas

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple