cluts: Incorrect test expectations in buf module (errno)

cluts: Incorrect test expectations in buf module (errno)

[Rich Felker]

Hi,
It seems cluts' buf module is surprised that strerror_r and ttyname_r
did not set errno to ERANGE. However these functions are not specified
to report anything in errno. Instead they return the error code
directly. This is an unfortunate inconsistency created in the early
days of "reentrant" (_r) functions due to confusion over whether errno
could be safely used in multithreaded programs. Note that some other
functions which return error codes directly are:

posix_* (posix_memalign etc.)
pthread_*

Rich

Re: cluts: Incorrect test expectations in buf module (errno)

[Luka Marčetić]

On 07/13/2011 03:51 PM, Rich Felker wrote:
> Hi,
> It seems cluts' buf module is surprised that strerror_r and ttyname_r
> did not set errno to ERANGE. However these functions are not specified
> to report anything in errno. Instead they return the error code
> directly. This is an unfortunate inconsistency created in the early
> days of "reentrant" (_r) functions due to confusion over whether errno
> could be safely used in multithreaded programs. Note that some other
> functions which return error codes directly are:
>
> posix_* (posix_memalign etc.)
> pthread_*
>
> Rich

Thanks, fixed (will push changes when I hear about SA_NODEFER).
I guess when you write your own implementation of those, you get to know 
them intimately ;-)
Luka.