Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!yale!cmcl2!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.lang.c
Subject: Re: qualifications in prototypes
Message-ID: <13501@smoke.BRL.MIL>
Date: 7 Aug 90 12:20:31 GMT
References: <386@taumet.com> <17240@haddock.ima.isc.com> <1896@tkou02.enet.dec.com>
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
Lines: 18

In article <1896@tkou02.enet.dec.com> diamond@tkou02.enet.dec.com (diamond@tkovoa) writes:
>In article <476@mtndew.UUCP> friedl@mtndew.UUCP (Stephen J. Friedl) writes:
>SF>	extern int stat(char *filename, struct stat *stptr);
>SF>Shouldn't the "filename" argument be const qualified?

More accurately, *filename should be const-qualified.

The relevant constraints are given in 3.3.16.1, in particular:
	both operands are pointers to qualified or unqualified versions
	of compatible types, and the type pointed to by the left [in
	this context, the declared function parameter] has all the
	qualifiers of the type pointed to by the right [the actual
	function argument].
Certainly, const char * has all the qualifiers of char *, as well as
one additional qualifier.

For practical examples, see many of the standard library functions in
section 4 of the standard.