Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 13 Mar 2001 01:49:26 +0000
From:      Brian Somers <brian@Awfulhak.org>
To:        Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
Cc:        net@FreeBSD.org, freebsd-standards@bostonradio.org, brian@Awfulhak.org
Subject:   Re: MAXHOSTNAMELEN redux 
Message-ID:  <200103130149.f2D1nQB08449@hak.lan.Awfulhak.org>
In-Reply-To: Message from Garrett Wollman <wollman@khavrinen.lcs.mit.edu>  of "Mon, 12 Mar 2001 13:13:22 EST." <200103121813.NAA61145@khavrinen.lcs.mit.edu> 

next in thread | previous in thread | raw e-mail | index | archive | help
Just some ramblings....

I find this a bit odd.  I concluded recently that NAME_MAX was the 
odd-one-out WRT not having the NUL only because it is the maximum 
size of a *component* of a path.  When the value is used, it makes 
sense to talk in terms of the without-NUL value.

This change seems to make it even more likely that people will forget 
whether MUMBLE_MAX includes the NUL or not.

If I were defining this sort of thing (hah!), I'd have *_LEN as 
definitions without NULs and *_SIZE as definitions with the NUL.  
*_MAX seems to be used more commonly as the maximum number of 
something (ARG_MAX, CHILD_MAX), so NAME_MAX seems to be a misspelt 
version of NAME_CHARS_MAX.... ditto for PATH_MAX and probably others.

Ok, I'm done :-)

> My bug report against the current POSIX draft was accepted.  For the
> record, here are the changes being made.  (``The indicated line'' is
> referring to a line in the definition of gethostname() where the
> length of the buffer was previously defined to be 256, including the
> terminating null.  The excluding-null semantics were chosen for
> parallel construction with {NAME_MAX} and similar constants.
> 
>  At the indicated line, for 255 substitute {HOST_NAME_MAX}.
>  At XBD page 261 (<limits.h>) before line 8966 insert:
> 
>    {HOST_NAME_MAX}
>      Maximum length of a host name (not including the terminating
>      null) as returned from the gethostname() function.
>      Minimum acceptable value: {_POSIX_HOST_NAME_MAX}
> 
>  Before line 9183, insert:
> 
>    {_POSIX_HOST_NAME_MAX}
>      Maximum length of a host name (not including the terminating
>      null) as returned from the gethostname() function.
>      Value: 255
> 
>  At XBD page 424 (<unistd.h>) before line 14818 insert:
> 
>    _SC_HOST_NAME_MAX
> 
>  At XSH page 1982 (sysconf()) before line 45530 insert:
> 
>    {HOST_NAME_MAX}       _SC_HOST_NAME_MAX
> 
>  I include the last two changes for completeness only; I do not
>  believe that applications are likely to use the sysconf() interface
>  for this purpose.
> 
> -GAWollman

-- 
Brian <brian@Awfulhak.org>                        <brian@[uk.]FreeBSD.org>
      <http://www.Awfulhak.org>;                   <brian@[uk.]OpenBSD.org>
Don't _EVER_ lose your sense of humour !



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200103130149.f2D1nQB08449>