Path: utzoo!attcan!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!adam.pika.mit.edu!scs
From: scs@adam.pika.mit.edu (Steve Summit)
Newsgroups: comp.lang.c
Subject: Re: hardcoded constants
Message-ID: <8512@bloom-beacon.MIT.EDU>
Date: 18 Dec 88 06:27:44 GMT
References: <15852@iuvax.cs.indiana.edu> <883@quintus.UUCP>
Sender: daemon@bloom-beacon.MIT.EDU
Reply-To: scs@adam.pika.mit.edu (Steve Summit)
Lines: 27

In article <883@quintus.UUCP> ok@quintus.UUCP (Richard A. O'Keefe) writes:
>henry@utzoo.uucp (Henry Spencer) writes:
>>-	foo = malloc(strlen(a)+strlen(b)+2);	/* 2 for '/' '\0' */
>>-Now, what's a good name for that "2", and how does naming it improve
>>-readability?
>
>I recently had a very similar problem.  A *superb* "name" for that 2 is
>		sizeof "/"

Was this suggestion supposed to include a :-) ?  sizeof("/") is a
very poor substitute, in this case: it gets the right answer for
the wrong reason.  (The '\0' the compiler counts in the string
constant "/" has little to do with the one which will be added
to the final, concatenated string.)

I once scratched my head over

	kill(HUP, 1);

in a program which had modified /etc/ttys and wanted to tell
/etc/init (process 1) to re-read it.  (This is more of a
unix-wizards than an info-c topic.)  Funny thing: man 2 kill
says it's kill(pid, signal), and yet the code worked just fine.
(Spoiler: HUP just happens to be 1).

                                            Steve Summit
                                            scs@adam.pika.mit.edu