Path: utzoo!attcan!uunet!husc6!mailrus!uflorida!haven!cvl!elsie!ado
From: ado@elsie.UUCP (Arthur David Olson)
Newsgroups: comp.lang.c
Subject: Re: hardcoded constants
Summary: When in doubt, do without
Message-ID: <8597@elsie.UUCP>
Date: 28 Dec 88 22:45:47 GMT
References: <1988Dec8.173158.11839@utzoo.uucp> <846@starfish.Convergent.COM> <1988Dec26.021757.15813@ziebmef.uucp>
Organization: NIH-LEC, Bethesda, MD
Lines: 16

> > . . .the malloc() call can be written:
> >	foo = malloc(Catspace(s,t) + sizeof('/'));
> 
>  For true safety, I'd write this as
>  	foo = malloc(Catspace(s,t)*sizeof(char) + sizeof('/'));

What we write in this neck of the woods is
	foo = ecpyalloc(s);
	foo = ecatalloc(foo, t);
where "ecpyalloc" sets foo pointing to an allocated copy of s
(a la "AllocCpy" in the 2.11.14 news software)
and "ecatalloc" sets foo pointing to a reallocation of foo with t catenated.
This avoids the need for a hardcoded constant entirely;
since you don't use one, you can't get its value wrong.
-- 
	Arthur David Olson    ado@ncifcrf.gov    ADO is a trademark of Ampex.