Re: [PATCH] mountlist/ptsname_r: leverage AC_HEADER_MAJOR

[Bruno Haible]

Hi Mike,

> These two modules use makedev/major/minor but don't have explicit
> checks for the functions.  Use the existing autoconf macro which
> will probe some headers for use and set up some defines.

Does this change fix a compilation problem? You did not say so.

Does this change make future maintenance easier? I don't think so.
mountlist.c and ptsname_r.c are quite special among Gnulib code:
they have #if sections for each particular platform. For example,
the ptsname_r.c file has
  - a code section for Solaris, that uses major, minor,
  - an #include section for Solaris, that includes the appropriate
    header,
  - a code section for AIX and OSF/1, that uses minor,
  - an #include section for AIX and OSF/1, that includes the appropriate
    header.
This is all consistent.

Solaris, AIX, OSF/1 won't change much in the future. I don't expect
that they will restructure their header files, in the way actively
developed platforms occasionally do.

There is also little chance that one will want to reuse the code for
Solaris, AIX, OSF/1 for any new platform. (GNU/Solaris? Not in
development.)

Similarly for mountlist.c.

So, all I can see is that your change will make configure times longer,
in particular on glibc and BSD systems, for no real purpose.

We have not split mountlist.c and ptsname_r.c into specific files, one
per platform:
  ptsname_r-solaris.c
  ptsname_r-aix-osf.c
  ptsname_r-generic.c
because we thought that maintenance is easier with a single file. Maybe
we should have done it?

Bruno