Re: who(1) exit status

[Andreas Schwab]

Eric Blake <address@hidden> writes:

> According to Shal-Linux-Ind on 6/23/2008 4:05 AM:
> | Hi,
> |
> | who(1) exit status is always 0.
> |
> | $ who --v
> | who (coreutils) 5.2.1
>
> Thanks for the report.  Consider upgrading - that is several years old,
> and the latest stable version is 6.12.  But I have confirmed that the
> issue still exists in git beyond 6.12:
>
> $ who /nosuch/file; echo $?
> 0

See the comment in read_utmp:

  /* Ignore the return value for now.
     Solaris' utmpname returns 1 upon success -- which is contrary
     to what the GNU libc version does.  In addition, older GNU libc
     versions are actually void.   */
  UTMP_NAME_FUNCTION (file);

When using the utmpname/setutent/getutmp family of functions there
really is no way to check for errors reading the file, since utmpname
does not actually try to open it, and setutent has no return value.

Andreas.

-- 
Andreas Schwab, SuSE Labs, address@hidden
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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