[Info-vax] The (now lost) future of Alpha.

[Craig A. Berry]

On 8/5/18 8:07 PM, Bill Gunshannon wrote:
> On 08/05/2018 08:55 PM, John Reagan wrote:
>> Read, write, etc. are not in a C standard. They are in POSIX.

Exactly, and on unixy systems they are native services (syscalls), not C
library functions.

> That's true, but the claim was that IBM Mainframes didn't
> have them and, obviously, they do.

No, the suggestion was that maybe on IBM mainframes they aren't
syscalls. They may be implemented in some other library, maybe even the
C library.

My point was that a compiler may well make use of various kinds of
native services as well as C library functions, and the C library
functions will themselves in many cases be implemented in terms of
native services. I'm sure various of the VMS compilers make use of OTS$
and STR$ and LIB$ and SYS$ routines in places even if they are written in C.

So I fully agree with Arne that there is no reason a compiler should
need to be written in assembler, but just had the minor quibble that it
may not always be desirable or possible to get by with only the C
library either.