Re: Return value for strcat and similar functions

From	Bartc <bc@freeuk.com>
Newsgroups	comp.lang.c
Subject	Re: Return value for strcat and similar functions
Date	2015-05-07 10:11 +0100
Organization	A noiseless patient Spider
Message-ID	<mifa6t$r28$1@dont-email.me> (permalink)
References	<michpc$2b0$1@dont-email.me>

Show all headers | View raw

On 06/05/2015 09:02, David Brown wrote:
> Does anyone know why the return value for strcat and similar library
> functions is defined in such an unhelpful (IMHO) way?
>
> The return value of strcat(s1, s2) is always s1, which is a value you
> already have available.  Returning a pointer to the end of s1 (i.e., s1
> + strlen(s1)) would be much more efficient when building up a string
> from parts.

It sounds a little like a deliberate decision to keep string lengths 
under wraps and not to let the programmer know what they were without 
explicitly calling strlen().

This might have sounded like an elegant concept back in 1970.

After all, if string lengths were available at nearly every stage, then 
it would tear apart the string library: you'd use memcpy instead of 
strcpy and strcat; you wouldn't need strcmp half the time (because the 
lengths were unequal, and for equal lengths you'd use memcmp); it would 
even obviate the need for a zero terminator in many cases!

-- 
Bartc

Back to comp.lang.c | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-06 10:02 +0200
  Re: Return value for strcat and similar functions Xavier Roche <xroche@free.fr.NOSPAM.invalid> - 2015-05-06 10:34 +0200
  Re: Return value for strcat and similar functions Lőrinczy Zsigmond <zsiga@nospam.for.me> - 2015-05-06 16:51 +0200
  Re: Return value for strcat and similar functions Keith Thompson <kst-u@mib.org> - 2015-05-06 08:58 -0700
    Re: Return value for strcat and similar functions Richard Heathfield <rjh@cpax.org.uk> - 2015-05-06 17:07 +0100
      Re: Return value for strcat and similar functions Morris Dovey <mrdovey@iedu.com> - 2015-05-06 12:01 -0500
    Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-07 10:19 +0200
      Re: Return value for strcat and similar functions glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-05-07 13:21 +0000
        Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-07 16:24 +0200
          Re: Return value for strcat and similar functions glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-05-07 18:02 +0000
      Re: Return value for strcat and similar functions Morris Dovey <mrdovey@iedu.com> - 2015-05-07 10:17 -0500
        Re: Return value for strcat and similar functions Morris Dovey <mrdovey@iedu.com> - 2015-05-07 10:56 -0500
          Re: Return value for strcat and similar functions asetofsymbols@gmail.com - 2015-05-07 11:00 -0700
            Re: Return value for strcat and similar functions Morris Dovey <mrdovey@iedu.com> - 2015-05-07 14:28 -0500
              Re: Return value for strcat and similar functions asetofsymbols@gmail.com - 2015-05-07 12:47 -0700
          Re: Return value for strcat and similar functions Nathan Wagner <nw@hydaspes.if.org> - 2015-05-08 09:31 +0000
        Re: Return value for strcat and similar functions Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-07 15:55 -0700
        Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-08 11:03 +0200
          Re: Return value for strcat and similar functions Morris Dovey <mrdovey@iedu.com> - 2015-05-08 05:07 -0500
  Re: Return value for strcat and similar functions Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-06 18:25 -0700
    Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-07 10:22 +0200
      Re: Return value for strcat and similar functions Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-07 15:39 -0700
        Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-08 11:09 +0200
          Re: Return value for strcat and similar functions Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-10 08:44 -0700
            Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-10 21:30 +0200
              Re: Return value for strcat and similar functions Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-11 20:42 -0700
                Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-12 09:52 +0200
                Re: Return value for strcat and similar functions Bartc <bc@freeuk.com> - 2015-05-12 13:33 +0100
                Re: Return value for strcat and similar functions Ike Naar <ike@iceland.freeshell.org> - 2015-05-14 20:15 +0000
                Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-14 23:06 +0200
                Re: Return value for strcat and similar functions Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-20 11:08 -0700
                Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-21 10:55 +0200
                Re: Return value for strcat and similar functions glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-05-21 13:05 +0000
                Re: Return value for strcat and similar functions David Brown <david.brown@hesbynett.no> - 2015-05-21 20:42 +0200
                Re: Return value for strcat and similar functions Tim Rentsch <txr@alumni.caltech.edu> - 2015-07-10 10:40 -0700
    Re: Return value for strcat and similar functions raltbos@xs4all.nl (Richard Bos) - 2015-05-08 21:56 +0000
      Re: Return value for strcat and similar functions Tim Rentsch <txr@alumni.caltech.edu> - 2015-05-10 09:07 -0700
  Re: Return value for strcat and similar functions Bartc <bc@freeuk.com> - 2015-05-07 10:11 +0100

csiph-web