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- An Update on UNIX* and C Standards Activities
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- August 1989
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- Jeffrey S. Haemer, Report Editor
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- USENIX Standards Watchdog Committee
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- IEEE 1003.5 Ada Language Update
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- Ted Baker (tbaker@ajpo.sei.cmu.edu) reports of the April 1989 meeting:
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- The Minneapolis meeting started off poorly. The chairman, co-
- chairman, and technical editor were absent, though each for good
- reasons. ("Co-chairman" is POSIX for vice-chairman.) Only one of the
- members present had received a copy of the latest draft (2.0). Many
- of the changes agreed upon at the last meeting (Fort Lauderdale) were
- not yet reflected in this draft. There was no agenda.
-
- Despite these handicaps, the group made considerable progress. Steve
- Deller acted as chair, working up an agenda and holding the group
- fairly closely to it. (Indeed, Steve Deller has now become an
- official co-chair, but is still doing a good job.)
-
- By the second day copies of Draft 2.0 had been made. This draft was
- reviewed completely, and several changes were approved. The hottest
- issue was how signals would be mapped to Ada task entries. Several
- semantic gaps in the P1003.1 C-language binding were discovered, and
- passed on to the P1003.1 working group.
-
- Most major semantic issues were, at this point, resolved.
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- 1. Each Ada program consists of a single POSIX process, or at least
- appears to be so through the POSIX/Ada interface.
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- 2. POSIX signals are handled by Ada tasks via the same mechanism as
- hardware interrupts, as logical entry calls.
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- 3. POSIX character and string types are distinct from the standard
- Ada character and string types.
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- 4. The C-binding's "errno" values are translated into distinct Ada
- exceptions.
-
- __________
-
- * UNIX is a registered trademark of AT&T in the U.S. and other
- countries.
-
- Jeffrey S. Haemer, Editor USENIX Standards Watchdog Committee
-
-
- August 1989 Standards Update - 2 - IEEE 1003.5 Ada Language
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- 5. The Ada-binding need not follow the organizational and naming
- conventions of the C-binding, especially where they violate
- principles of data abstraction.
-
- What remains is filling in a lot of details, including most of the
- text of the document, and making it stylistically consistent.
-
- Group members volunteered to edit the agreed-upon changes into the
- draft document, while filling in missing text. This work was to be
- completed before May 10-12, at which time a subset of the working
- group would meet in Bedford Mass. for a "writing party". The goal of
- this party would be to catch up, completing all missing portions of
- the draft, so that it could be submitted for mock ballot before the
- July P1003 meeting. There was some question whether this goal would
- be met. (The mock ballot date was missed, so it appears 1003.5 won't
- have an official Ada language binding that corresponds to 1003.1 by
- end-of-year 1989.)
-
- There were also coordination meetings (BOFs) with the groups working
- on language-independent specifications (P1003.1) and threads
- (P1003.4). The Ada group seemed generally pleased with progress on
- the language-independent specification, and hopes that the draft Ada-
- binding will provide some guidance to that activity. The group is
- less pleased with the tendency of other groups (e.g. P1003.2 and
- P1003.4) to aggravate the problem of C-dependencies in their draft
- documents.
-
- The Ada group is very interested in having the 1003.4 standard include
- multi-threaded processes, but is very concerned that any such standard
- be compatible with the semantics of Ada tasks. Some of the preliminary
- proposals coming out of the threads working group do not seem to be
- compatible with this goal.
-
- Jeffrey S. Haemer, Editor USENIX Standards Watchdog Committee
-
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-