Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!wuarchive!udel!princeton!notecnirp!nfs
From: nfs@notecnirp.Princeton.EDU (Norbert Schlenker)
Newsgroups: comp.os.minix
Subject: Re: 1.5.0 upgrade: REPORT + BUGS + PATCHES
Message-ID: <22990@princeton.Princeton.EDU>
Date: 11 Jan 90 19:17:02 GMT
References: <1990Jan7.205429.5247@chinet.chi.il.us> <363@fwi.uva.nl>
Sender: news@princeton.Princeton.EDU
Reply-To: nfs@notecnirp.UUCP (Norbert Schlenker)
Organization: Dept. of Computer Science, Princeton University
Lines: 31

In article <363@fwi.uva.nl> croes@fwi.uva.nl (Felix A. Croes) writes:
|In article <1990Jan7.205429.5247@chinet.chi.il.us> bill@chinet.chi.il.us (Bill Mitchell) writes:
|> [stuff deleted]
|>This is apparently due to some problem below readdir(), so dp->d_name 
|>isn't returned as expected.  Things got complicated pretty fast here.
|>Knowing nothing about POSIX stuff, I didn't feel qualified pursue it.
|>I did notice that /usr/include/dirent.h had struct dirent.d_name
|>declared as "char d_name[1]", which looked suspicious.
|
|I don't know about POSIX, but it should be at least 14. It was 14 in Minix 1.3,
|since file names in directories are 14 bytes long. However, using 14 will cause
|problems with numerous incorrect programs which assume that file names in
|directories always terminate in \0 (ever tried 1.3 tar?).
|
|The comment says: /* name of file plus a 0 byte */ , so perhaps 15 should be
|used? Does any POSIX wizard know?
|
|Felix Croes    (croes@fwi.uva.nl)

I'm no POSIX wizard, but the declaration is reasonable.  There has been a long
discussion of this in comp.lang.c, the apparent conclusion of which is that
this is a reasonably portable construct for a structure that is built by
some trusted routine and for which a pointer is returned to a caller (like
the return values from readdir()).

It was pointed out that the structure definition gives the average programmer
the idea that actually allocating such a beast is reasonable.  Regrettably,
this isn't the case here.  Do NOT write programs that use this structure
definition - write programs that use a pointer to it.

Norbert