Re: baffled by glibc

Bernhard Rosenkraenzer (bero@glibc.ml.org)
Sun, 18 Jan 1998 19:15:30 +0000 (GMT)




On Sun, 18 Jan 1998, Michal Jaegermann wrote:

> Can somebody explain why this header separation between glibc and kernel,
> touted as "the best thing from a sliced bread", is really such a good
> thing? The only answer I have seen so far is that this will allow
> independent changes of various structures and definitions in kernel
> headers.

Also, it allows you to write a program once, and run it on tons of
different operating systems without making any changes.
If you rely on kernel includes, you have to make tons of changes to port a
program from, for example, FreeBSD to Linux or vice versa.
With glibc, you simply recompile it, and you have a working Linux version
of the program.

> That is the point! A lot of system utilities **has** to know these sizes.
> So far I have seen on this list a breakage in NFS, ncpfs, smbfs caused
> by a mismatch in definitions between these two sets of headers

Necessary in the switch - once every application is ported to work with
glibc (most of the important ones are, by now), it's ok - and you won't
have to rewrite NFS etc. every time the kernel is updated.

LLaP
bero

-- bero@bero-online.ml.org - ICQ/UIN 6545964 - http://www.star-trek.ml.org/ --

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-- logical conclusion