Re: PATCH: access to names of errors

[Oliver Kiddle <okiddle@yahoo.co.uk>]

Peter wrote:
> This patches the parameter module to add $sys_errnos, which turns $ERRNO
> into the name of the error --- not the error text you would get with
> strerror(), the standard name.  This is more useful for programming,
> since if you know you can test for
> 
> [[ $sys_errnos[$ERRNO] = EINTR ]]
> 
> and so on.  It's also more difficult, but I simply copied the code for
> signal names.
> 
> I'd appreciate comments on
> - where this should appear; I'm planning on an interface to the system
>   read function and it could go there instead.  This might be
>   better since the parameter module usually provides shell rather
>   than system information and the new array bloats it somewhat.
>   The new module could be a generic zsystem module.

I'd say it shouldn't be in the parameter module because as you say, that
interfaces to shell rather than system information. I'd just call the
module `system'. The `z' seems a bit redundant especially as it is
effectively zsh/system with the namespace.

> - what it should be called; the current name at least paves the way
>   for a move into a different namespace such as $sys.errnos, should
>   anybody ever have the time to rewrite the parameter code completely

I'd have thought just $errnos would be fine. Especially if it can be in
a system namespace in the long term.

> - what else we should provide; strerror() would be fairly easy, but
>   an array would probably have to be generated specially during
>   configuration, because the internal system array seems to be
>   non-standard.  We can check for _sys_errlist and _sys_nerr first,
>   perhaps.

By during configuration, do you mean by autoconf? When the module is
loaded would be better. If it's in an out of the way module that isn't
loaded by default, I don't think it matters. That long over due parameter
code rewrite will have to allow individual array elements to be generated
on demand.

Oliver

________________________________________________________________________
This email has been scanned for all viruses by the MessageLabs Email
Security System. For more information on a proactive email security
service working around the clock, around the globe, visit
http://www.messagelabs.com
________________________________________________________________________