From:	Hans-Bernhard Broeker <broeker AT acp3bf DOT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: What is the canonical way to find out if a file exists (in g++)?
Date:	6 Jan 2000 16:53:43 GMT
Organization:	Aachen University of Technology (RWTH)
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Mike Demoulin <mad AT intersurf DOT com> wrote:
> On Thu, 6 Jan 2000 12:22:12 +0200 (IST),
>     Eli Zaretskii <eliz AT is DOT elta DOT co DOT il> wrote:
>>
>>If you are looking for a long file name on NT, DJGPP programs won't
>>find it.  Try "dir /x" and look for the short 8+3 alias: that's all
>>DJGPP programs are allowed to see on NT.

> Is there a function to convert from an LFN to its 8+3 alias (without using
> the dir/x)?

No, at least not a general one. The short alias is chosen at file
creation time, based on the long name, and on what other short names
are already present in the same directory. That makes the short name
essentially random. Without accessing the actual LFN file, there's not
the slightest chance you'll ever know for sure which of the
short-named files corresponds to it.

Which is the major reason many have called the whole concept of 8+3
alias names brain-damaged. A single file having 2 partly independent
names, one of which can change randomly behind your back, in certain
situations, is a major pain in the lower back, at times. It might have
been better to just hide all non-8.3 names from DOS programs, right
away...


-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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