Re: Linux-asm (was A patch for linux 2.1.127)

Richard B. Johnson (root@chaos.analogic.com)
Wed, 18 Nov 1998 08:48:45 -0500 (EST)


On Tue, 17 Nov 1998, Manuel J. Galan wrote:

> Some common places and/or common sense:
>
> * UNIX was built on C and C was built for UNIX.
>

Unix was built on a Digital PDP-11/34, using tools available
in the RSX-11 Digital Operation system. Most of the 'hardware stuff'
was done in DEC MACRO Assembly under RSX-11.

'C' came later.

> * UNIX/C were devised with portability in mind.
>

Unix and C are not the same thing. Once Unix was running, a
'C' compiler was built (from the ideas of 'B') so that the
machine would not have to be rebooted to get at the DEC tools
to continue development.

> * To speed up your programs, improve your algorithms.
> ( i.e. see last posting by Benoit Poulot-Cazajous)
>

'C' is a tool. That's all. There are other tools available
which, combined, are known as a 'programming environment'.


> * Linus himself seems to be quite a good assembler
> programmer but he made Linux kernel in C, (hint, hint...)
>

Using Linus' name is a usual trick. He did not make the kernel
in 'C'. It was made using various tools including assembler and
GNU extensions that are implemented within the GNU Compiler.
Check the ../linux/arch/.. directories and the ../linux/include/asm
directories before you leap to such a conclusion.

Further, much of the new 'C' libraries are written in assembly.
Basically, the hard stuff is written in assembly so you can make
portable code that runs reasonably well.

Cheers,
Dick Johnson
***** FILE SYSTEM WAS MODIFIED *****
Penguin : Linux version 2.1.127 on an i686 machine (400.59 BogoMips).
Warning : It's hard to remain at the trailing edge of technology.

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