Unix/C program modularity

[Heiby]

In article <2474 at brl-tgr.ARPA> jss at UCB-VAX.Berkeley.EDU writes:
>A question about database systems, however.  Unix provides fixed length record
>access, but not locking.  While I agree that a database library should be
>external to the kernel (sp?), I think that named and unnamed semaphores and
>file byterange locking should be added to the kernel, as these would provide
>the basis for a great deal of flexibility not presently available.

I'm afraid that jss shows his UCB orientation in the above.  UNIX does have
file and record locking (byterange) in the kernel.  References are the
1984 /usr/group Standard prepared by the /usr/group Standards Committee
November 14, 1984 and the System V Interface Definition, Issue 1, Spring 1985.
The former is available from /usr/group, the latter from AT&T (select code
is 307-127).  What jss probably meant to say was that these features should
be incorporated into 4bsd, with which I tend to agree.  (I know that there
are no named semaphores in UNIX.  It sounds like an interesting idea.)
-- 
Ron Heiby {NAC|ihnp4}!cuae2!heiby   Moderator: mod.newprod & mod.unix
AT&T-IS, /app/eng, Lisle, IL	(312) 810-6109
"I am not a number!  I am a free man!" (#6)