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Re: [BUG/PATCH] setup: Copy an environment variable to avoid overwrites

From
David Michael <fedora.dm0@gmail.com>
Date
Jan 5, 2013, 02:15 UTC
Message-ID
<CAEvUa7mbs7rfGdfzbGb9p889K7GUbXFg9TUcFWFYKt8+8AKCiQ@mail.gmail.com>
In-Reply-To
<7vsj6gqvhc.fsf@alter.siamese.dyndns.org>
Hi,
On Fri, Jan 4, 2013 at 8:17 PM, Junio C Hamano <gitster@pobox.com> wrote:
Show 8 quoted lines
> In fact,
>
>     http://pubs.opengroup.org/onlinepubs/9699919799/functions/getenv.html
>
> says that only setenv(), unsetenv() and putenv() may invalidate
> previous return values.  Note that getenv() is not listed as a
> function that is allowed to break return values from a previous call
> to getenv().

Before I sent the e-mail, I checked that very page to be sure I wasn't entirely insane. Specifically, the second paragraph begins with:

> The string pointed to may be overwritten by a subsequent call to getenv(), [...]

I read that line as confirmation that this is indeed acceptably standard behavior. Even the getenv man page on my Fedora workstation says:

> The string pointed to by the return value of getenv() may be statically allocated, and can be modified by a subsequent call to getenv(), putenv(3), setenv(3), or unsetenv(3).
Am I misinterpreting these statements?
Thanks.
David
Previous: Junio C HamanoNext: Junio C Hamano
Message 3 of 14 in “setup: Copy an environment variable to avoid overwrites”
  1. setup: Copy an environment variable to avoid overwritesDavid Michael, Jan 5, 2013
  2. Junio C HamanoJan 5, 2013
  3. David MichaelJan 5, 2013
  4. Junio C HamanoJan 5, 2013
  5. Duy NguyenJan 5, 2013
  6. Junio C HamanoJan 5, 2013
  7. Duy NguyenJan 5, 2013
  8. Junio C HamanoJan 5, 2013
  9. Add getenv.so for catching invalid getenv() use via LD_PRELOADNguyễn Thái Ngọc Duy, Jan 5, 2013
  10. Matt KraaiJan 5, 2013
  11. Duy NguyenJan 5, 2013
  12. Jonathan NiederJan 5, 2013
  13. David MichaelJan 7, 2013
  14. Erik Faye-LundJan 7, 2013

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