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Re: possible code error at run_command.c

From
Johannes Sixt <j.sixt@viscovery.net>
Date
Dec 21, 2009, 07:18 UTC
Message-ID
<4B2F214D.2020905@viscovery.net>
In-Reply-To
<1976ea660912202246k45732bf2p111bbeb78047693e@mail.gmail.com>
Frank Li schrieb:
Show 8 quoted lines
> int start_command(struct child_process *cmd)
> {
> 	int need_in, need_out, need_err;
> 	int fdin[2], fdout[2], fderr[2];
> 	int failed_errno = failed_errno;
> 
> I have not found failed_errno as global variable.
> failed_errno = failed_errno means nothing.

This is a commonly used idiom to avoid an (incorrect) compiler warning about an uninitialized variable.

Strictly speaking, I think that you are right by saying "means nothing" because the use of the uninitialized variable invokes undefined behavior (and for this reason, I dislike this construct), but in practice it will not make a difference.

-- Hannes
Previous: Wincent ColaiutaNext: Frank Li
Message 3 of 11 in “possible code error at run_command.c”
  1. Frank LiDec 21, 2009
  2. Wincent ColaiutaDec 21, 2009
  3. Johannes SixtDec 21, 2009
  4. Frank LiDec 21, 2009
  5. Johannes SixtDec 21, 2009
  6. Frank LiDec 21, 2009
  7. Johannes SixtDec 21, 2009
  8. Erik Faye-LundDec 21, 2009
  9. Johannes SixtDec 21, 2009
  10. Erik Faye-LundDec 21, 2009
  11. Frank LiDec 21, 2009

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