Re: [ECOS] Re: Bug in sem_getvalue

[Jonathan Larmour <jlarmour at redhat dot com>]

"Woller, Thomas" wrote:
> 
> The sem_getvalue() function shall update the location referenced
> by the sval argument to have the value of the semaphore
> referenced by sem without affecting the state of the semaphore.
> The updated value represents an actual semaphore value that
> occurred at some unspecified time during the call, but it need
> not be the actual value of the semaphore when it is returned to
> the calling process.
> If sem is locked, then the value returned by sem_getvalue() is
> either zero or a negative number whose absolute value represents
> the number of processes waiting for the semaphore at some
> unspecified time during the call.
> RETURN VALUE
> Upon successful completion, the sem_getvalue() function shall
> return a value of zero. Otherwise, it shall return a value of -1
> and set errno to indicate the error.
> since there is only one (1) process in eCos (only threads), does
> this mean that no matter how many threads are waiting on the
> semaphore that the value returned in the sval argument will be
> never be <-1 (e.g., -2, -3,...)?

Strictly yes. Although the change I made to eCos was to just return 0
always.

Jifl
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