Re: sizeof environment variables array = 1?

From	Keith Thompson <kst-u@mib.org>
Newsgroups	comp.lang.c
Subject	Re: sizeof environment variables array = 1?
Date	2017-06-08 11:51 -0700
Organization	None to speak of
Message-ID	<lnr2yuia7m.fsf@kst-u.example.com> (permalink)
References	<ohbpd7$5r3$2@dont-email.me> <878tl2v5ge.fsf@gmail.com>

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Gareth Owen <gwowen@gmail.com> writes:
> DFS <nospam@dfs.com> writes:
>
>> int main(int argc, char *argv[], char *env[])
>> {
>>   printf("%d\n",sizeof(env)/sizeof(env[0]));
>>   return(0);
>> )
>>
>> Output is 1.
>>
>> Why?
>
> Anything that looks like an array object - when used in the argument
> list of a function, is not an array object, but "decays" into a pointer.

The word "decay" is usually used to refer to the implicit conversion of
an array expression to a pointer expression, that occurs in all but 3
contexts.  The adjustment of an array parameter to a pointer parameter
is covered by a different language rule.  (Both are done purely at
compile time; there is no run-time conversion.)

[...]

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-08 11:13 -0400
  Re: sizeof environment variables array = 1? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2017-06-08 11:25 -0400
    Re: sizeof environment variables array = 1? Keith Thompson <kst-u@mib.org> - 2017-06-08 09:34 -0700
      Re: sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-08 13:14 -0400
        Re: sizeof environment variables array = 1? jameskuyper@verizon.net - 2017-06-08 10:51 -0700
  Re: sizeof environment variables array = 1? Gareth Owen <gwowen@gmail.com> - 2017-06-08 16:56 +0100
    Re: sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-08 12:18 -0400
      Re: sizeof environment variables array = 1? scott@slp53.sl.home (Scott Lurndal) - 2017-06-08 16:35 +0000
      Re: sizeof environment variables array = 1? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2017-06-08 12:43 -0400
        Re: sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-08 13:49 -0400
          Re: sizeof environment variables array = 1? "James R. Kuyper" <jameskuyper@verizon.net> - 2017-06-08 13:58 -0400
            Re: sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-08 14:45 -0400
          Re: sizeof environment variables array = 1? Keith Thompson <kst-u@mib.org> - 2017-06-08 12:10 -0700
            Re: sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-09 11:21 -0400
            Re: sizeof environment variables array = 1? Richard Heathfield <rjh@cpax.org.uk> - 2017-06-09 16:23 +0100
              Re: sizeof environment variables array = 1? "James R. Kuyper" <jameskuyper@verizon.net> - 2017-06-09 11:48 -0400
                Re: sizeof environment variables array = 1? Richard Heathfield <rjh@cpax.org.uk> - 2017-06-09 16:53 +0100
                Re: sizeof environment variables array = 1? "James R. Kuyper" <jameskuyper@verizon.net> - 2017-06-09 12:18 -0400
                Re: sizeof environment variables array = 1? Richard Heathfield <rjh@cpax.org.uk> - 2017-06-09 17:28 +0100
                Re: sizeof environment variables array = 1? Keith Thompson <kst-u@mib.org> - 2017-06-09 09:12 -0700
              Re: sizeof environment variables array = 1? "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-10 09:28 +0200
          Re: sizeof environment variables array = 1? jak <please@nospam.tnx> - 2017-06-08 22:18 +0200
            Re: sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-08 17:31 -0400
              Re: sizeof environment variables array = 1? Keith Thompson <kst-u@mib.org> - 2017-06-08 15:12 -0700
                Re: sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-09 11:21 -0400
                Re: sizeof environment variables array = 1? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-09 16:39 +0100
                Re: sizeof environment variables array = 1? Gareth Owen <gwowen@gmail.com> - 2017-06-10 07:26 +0100
                Re: sizeof environment variables array = 1? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-10 13:21 +0100
                Re: sizeof environment variables array = 1? gordonb.q80bx@burditt.org (Gordon Burditt) - 2017-06-10 17:32 -0500
                Re: sizeof environment variables array = 1? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-11 01:01 +0100
                Re: sizeof environment variables array = 1? luser droog <luser.droog@gmail.com> - 2017-06-11 01:28 -0700
                Re: sizeof environment variables array = 1? raltbos@xs4all.nl (Richard Bos) - 2017-06-17 18:38 +0000
                Re: sizeof environment variables array = 1? Keith Thompson <kst-u@mib.org> - 2017-06-09 08:41 -0700
                Re: sizeof environment variables array = 1? "James R. Kuyper" <jameskuyper@verizon.net> - 2017-06-09 11:50 -0400
                Re: sizeof environment variables array = 1? raltbos@xs4all.nl (Richard Bos) - 2017-06-17 18:37 +0000
                Re: sizeof environment variables array = 1? DFS <nospam@dfs.com> - 2017-06-18 09:11 -0400
          Re: sizeof environment variables array = 1? "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-10 09:19 +0200
      Re: sizeof environment variables array = 1? Robert Wessel <robertwessel2@yahoo.com> - 2017-06-08 12:44 -0500
    Re: sizeof environment variables array = 1? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-08 18:01 +0100
      Re: sizeof environment variables array = 1? Gareth Owen <gwowen@gmail.com> - 2017-06-08 18:45 +0100
    Re: sizeof environment variables array = 1? Keith Thompson <kst-u@mib.org> - 2017-06-08 11:51 -0700

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