[comp.misc] POSIX

tantuico@andromeda.rutgers.edu.rutgers.edu (Samuel B Tantuico) (02/15/89)

What is POSIX?  I've heard it before in a conversation, but I don't know
what it is?

Thanks, in advance!

sAm

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 Rutgers-Newark COSII   ||   tantuico@andromeda.rutgers.edu 
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boykin@calliope.Encore.COM (Joe Boykin) (02/17/89)

In article <2393@galaxy> tantuico@andromeda (Samuel B Tantuico) writes:
>What is POSIX?  I've heard it before in a conversation, but I don't know
>what it is?


POSIX is a set of application portability standards.  The group is
sponsored by the IEEE Computer Societies Technical Committee on Operating
Systems, and has been for the past 5 years or so.  While based on
UNIX(tm), there is nothing which says a POSIX compliant system needs to
be based on UNIX.  In fact, a number of vendors are looking to
provide POSIX compliance on non-UNIX systems.

The goal of the standards committees is to develop a set of standards
which will provide application portability at the source code level.
If you are given a POSIX compliant system, and only write code which
conforms to the POSIX standard (rather than extensions which a vendor
might also include), you should be able to take your program to another
POSIX compliant system, compile and run it with the same results.

POSIX is also a "philosophy".  The effort is certainly not complete,
nor will it be complete for many years.  It typically takes a minimum
of three years for a document to be produced and balloted.  The goal
of those working on POSIX is to continue defining standards until
a "complete" environment is present.  We have one piece now (see
below), others are being balloted now or are about to be, and more
will be balloted in the months and years to come.

POSIX is divided into a number of different areas.  1003.1 comprises
the "system interface" definition; i.e. the system call interface.  
This is the only document which has been balloted and approved as
an ANSI (American National Standards Institute) standard.  It is
currently being worked on for ISO (International Standards Organization)
approval.  While this is an approved standard, it is not static.
Additions and clarifications are already being worked on for
balloting at a future date.

P1003.2 is the "user interface" i.e. Shell command level.  The first
ballot for this went out about two months ago.  It generally takes
anywhere from a few months to a year from this point for an approved
standard to emerge.

P1003.3 is test methods, i.e. how do you validate that you have a standard
conforming system.

P1003.4 is "real-time" extensions (although the group has taken on quite
a bit of other work as well).


P1003.5 is language bindings.  P1003.1 is C language specific.  We are
currently working on both Ada and Fortran bindings.

P1003.6: Security.

P1003.7: System Administration

P1003.8: Networking

We also have study groups looking at Supercomputing and Transaction
processing issues.  These may develop into a "dot" group.

If you would like to get involved you should contact:

	Jim Isaak
	DEC, MSZK03-3/Y25
	110 Spit Brook Road
	Nashua, NH   03062
	603-881-0480


Hope this helps.

----

Joe Boykin
Encore Computer Corp
Past-Chairman, IEEE Computer Societies'
    Technical Committee on Operating Systems

UUCP: encore!boykin
ARPA: boykin@encore.com