Re: ENOTSUP vs EOPNOTSUPP

[Scott Bambrough <scottb@corelcomputer.com>]

Roland McGrath wrote:
> 
> Please explain the following change:
> 
>     1999-01-22  Ulrich Drepper  <drepper@cygnus.com>
> 
>             * sysdeps/gnu/errlist.awk: Mark ENOTSUP as alias for EOPNOTSUPP.
> 
> I do not think it is correct.  Moreover, such a change should never be made
> without discussion, because it affects multiple platforms, and affects the
> universal glibc API.
> 
> I added ENOTSUP because it is a 1003.1-specified error and we did not have
> it before.  I considered for some time making it and EOPNOTSUPP two names
> for the same thing.  1003.1 does not specify EOPNOTSUPP, so it says nothing
> on the subject.  I do not have the draft for the 1003.1[a-z] sockets spec,
> so I don't know what it says.
> 
> I did look at the Unix98 spec, which specifies both ENOTSUP and EOPNOTSUPP.
> It furthermore specifies that all the error codes it specifies must be
> unique values, with the specific exception that EAGAIN might == EWOULDBLOCK.
> For that reason, I concluded ENOTSUP must be distinct from EOPNOTSUPP.

I ran into a problem building tcl with these two.  They were case entries in a
switch statement.
Just my two cents worth.

Scott