Re: Now this is just annoying.

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From	Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups	comp.lang.c++
Subject	Re: Now this is just annoying.
Date	Mon, 03 Feb 2025 15:33:42 -0800
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scott@slp53.sl.home (Scott Lurndal) writes:
> Bonita Montero <Bonita.Montero@gmail.com> writes:
>>Am 02.02.2025 um 19:05 schrieb Scott Lurndal:
>>> $ gcc --version
>>> gcc (GCC) 14.2.1 20240912 (Red Hat 14.2.1-3)
>>> 
>>> $ g++ -O3  -o /tmp/a /tmp/a.cpp
>>> /tmp/a.cpp:4:1: warning: 'int main(int, const char**, const char**, const char**)' takes only zero or two arguments [-Wmain]
>>>      4 | main(int argc, const char **argv, const char **envp, const char **auxv)
>>>        | ^~~~
>>> 
>>> So much for backward compatibility and support for the original C++ operating
>>> environment (unix).
>>
>>Use getenv() - you don't need environment-variables you don't know.
>
> There are a number of use cases where your blanket statement is false.

It's both false (try implementing the printenv command with just
getenv()) and irrelevant.  It's the 4th parameter to main, auxv, that
triggers the warning.  And the environment vector can be accessed either
by defining
    char **envp
as a parameter to main, or by declaring
    extern char **environ;
(The envp parameter is a common extension, but it's not specified by
POSIX.  environ is.)

And the information provided by the auxv parameter can be accessed via
the getauxval() function *if* your implementation provides it.
Apparently it's specific to ELF executables.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

Thread

Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-02 18:05 +0000
  Re: Now this is just annoying. red floyd <no.spam.here@its.invalid> - 2025-02-02 11:05 -0800
    Re: Now this is just annoying. Muttley@DastardlyHQ.org - 2025-02-03 08:55 +0000
    Re: Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-03 14:02 +0000
      Re: Now this is just annoying. Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-02-03 15:34 -0800
  Re: Now this is just annoying. Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-02-02 15:22 -0800
    Re: Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-03 14:05 +0000
  Re: Now this is just annoying. James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-02-02 18:43 -0500
    Re: Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-03 14:06 +0000
      Re: Now this is just annoying. Muttley@DastardlyHQ.org - 2025-02-03 14:10 +0000
      Re: Now this is just annoying. Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-02-03 15:21 -0800
        Re: Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-03 23:54 +0000
  Re: Now this is just annoying. Bonita Montero <Bonita.Montero@gmail.com> - 2025-02-03 15:16 +0100
    Re: Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-03 17:46 +0000
      Re: Now this is just annoying. Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-02-03 15:33 -0800
      Re: Now this is just annoying. Bonita Montero <Bonita.Montero@gmail.com> - 2025-02-04 07:20 +0100
        Re: Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-04 14:30 +0000
          Re: Now this is just annoying. Bonita Montero <Bonita.Montero@gmail.com> - 2025-02-04 17:25 +0100
            Re: Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-04 20:20 +0000
          Re: Now this is just annoying. Bonita Montero <Bonita.Montero@gmail.com> - 2025-02-05 08:53 +0100
            Re: Now this is just annoying. scott@slp53.sl.home (Scott Lurndal) - 2025-02-05 15:09 +0000
              Re: Now this is just annoying. Bonita Montero <Bonita.Montero@gmail.com> - 2025-02-05 16:11 +0100
                Re: Now this is just annoying. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2025-02-05 11:46 -0800

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