>>> The call to call_onauth should probably return the exit status of the
>>> onauth script, which can be gotten after the wait(&pid) call
>>> returns.  And
>>> instead of returning 0 for a failed call, return -1.  I'm not sure
>>> if we
>>> care about that, but it's information that might be useful later on.
>> personally i would go with "1" for good and "0" for bad, but i can
>> see the logic here as well- just return the exit status code from wait
>> () or waitpid(). as long as it's clearly documented, i can go either
>> way.
> Well, we run into a minor issue, but I think I can resolve it fairly
> simply.    We need to return "internal" error codes if we have problems
> running the script, but we need to return "external" error codes if the
> script returns non-zero.  I propose that we return codes >= 256 for
> "internal" errors (in the case of ENOENT or EACCES, either bit-shift them
> or add 256 (probably simpler to add 256), and return "external" error
> codes as-is.  Either way, 0 is a success.  What do you think?  I'd like to
> keep our APIs consistant in this manner.

>> also, the parameter to wait() is not the address of "pid"... it's the
>> address of the integer where the exit status will be stored. it
>> doesn't matter right now, but after your discussion about returning
>> the exit code, that makes sense- so i've added that.
> I thought about that and figured why not reuse the existing variable, but
> there's no reason not to use another one either (4 bytes of memory is
> pretty cheap these days :)).
In looking at the man page for wait(), the value returned in rv is NOT the
actual return code, it's bit-shifted by 256.  You need to use the macro
WEXITSTATUS(rv) to get the actual exit code.  So we can return rv directly
or unmodified E{NOENT|ACCES}, and just know that if the return value is >
256 that we have to bit-shift it back to get the actual exit code...  I
think that works just fine.

Joshua Megerman
SJGames MIB #5273 - OGRE AI Testing Division
You can't win; You can't break even; You can't even quit the game.
  - Layman's translation of the Laws of Thermodynamics

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