Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!taumet!steve
From: steve@taumet.com (Stephen Clamage)
Newsgroups: comp.lang.c++
Subject: Re: bug in istrstream example?
Message-ID: <724@taumet.com>
Date: 11 May 91 19:30:37 GMT
References: <1991May11.015836.1556@neon.Stanford.EDU>
Organization: Taumetric Corporation, San Diego
Lines: 24

philip@pescadero.stanford.edu (Philip Machanick) writes:

>In both Lippman (p. 414) and the cfront 2.0 Library Manual (p 3.12) examples
>roughly of the form
>  char s[] = "400"
>  istrstream iss (s,sizeof(s));
>appear. Presumably, sizeof is a bug (since this will always return the size of
>a pointer when applied to an array), and what is really required is strlen(s) -
>or should it be strlen(s)+1 to allow for the null char at the end?

>Has this been fixed in later editions / printings?

There is nothing to fix.  An array is not converted to a pointer when
it is the object of the sizeof operator, so the result of sizeof(s)
is the number of elements of s times the element size.

Given	char *s = "hello";	s is declared as a pointer, not an array,
so sizeof(s) is the size of the pointer.

Given	extern char s[];	sizeof(s) is illegal,
since the size of s cannot be determined.
-- 

Steve Clamage, TauMetric Corp, steve@taumet.com