Re: find-library-name fails if file (with no extension) exists.

[Lennart Borgman <lennart.borgman.073@student.lu.se>]

David Kastrup wrote:
> Lennart Borgman <lennart.borgman.073@student.lu.se> writes:
> 
>> David Kastrup wrote:
>>
>>> It is not even possible to write code with a reasonable chance of
>>> working reliably since one can have Windows and Unix file systems on
>>> the same system and export either with Samba or NFS or a number of
>>> other ways.
>> If (a very big IF perhaps) Samba, NFS etc preserves the case of file
>> names in each export and the software is written with the possibility
>> of both case sensitive and case insensitive file systems in mind it
>> seems possible to me.
>>
>> Or am I missing something there?
> 
> You can't decide that two file names might indicate the same file
> without doing an actual file operation.  You can't decide whether
> writing a file would conflict with an existing file without actually
> doing the write (and asking the operating system to fail in case the
> file exists).  You can't really base any decision on existing file
> names.  As a rule of thumb, if there is a possibility for a race
> condition, there is a possibility for filename aliasing trouble.  And
> not every potential race condition is a problem.
> 
> Things like file name completion are simply something which is
> impossible to get right.


But does not that depend on the use of file names? If file names are 
choosen so that they work on both case insensitive and case sensitive 
system are there then any problems? At least that has been the problem 
in the cases I have seen. Most often the problem has actually been that 
someone writing on a case sensitive file system forgot to take care of 
this. (That is of course an easy mistake to make.)

I am aware of the cases you mentioned to Juanma where there really are 
no way to do lowercase/uppercase certain letters. Could not they be 
handled (and are they not already handled) as different letters even 
though they outside the computer world may look at uppercase/lowercase 
variants of the same letter?