From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.5-pre1 (2020-06-20) on ip-172-31-74-118.ec2.internal X-Spam-Level: X-Spam-Status: No, score=-0.5 required=3.0 tests=BAYES_05 autolearn=ham autolearn_force=no version=3.4.5-pre1 Date: 7 Aug 91 01:35:50 GMT From: telesoft!rlk@uunet.uu.net (Bob Kitzberger @midnight) Subject: Re: Ada and Unix--Blocked Tasks Message-ID: <1991Aug7.013550.13121@telesoft.com> List-Id: Many excellent points have been made on this thread in support of the de facto practice of mapping multiple Ada tasks onto a single Unix process -- increased efficiency, necessity due to the shared- memory model of Ada task hierarchies, etc. Of course, any serious software system must make numerous tradeoffs, and I believe that we've made the right ones. The majority of developers would scream bloody murder if a rendezvous took as long as a Unix context switch, which is only one of the implications of a one-to-one mapping of Ada tasks to Unix processes. When Unix supports threads/lightweight processes (ref. current POSIX work), rest assured that you'll see Ada implementations taking full advantage of them. Ada has just beaten Unix to the punch by five or ten years ;-) As further data points, TeleSoft's MVS development system supports the ability to map M tasks to N MVS processes. Our Sun 3 and Sun 4 development systems map all of the Ada tasks (within a single Ada program) onto a single Unix process. Non-blocking I/O is provided for Text_IO. Other than Text_IO, I recommend using an earlier poster's fcntl() and SIGIO/Interrupt entry solution. Thanks for the feedback indicating how strongly people desire a stronger cooperation between Unix and Ada tasking. if you have specific requirements, I suggest that you contact your vendor's marketing department... we honestly want to develop the tools that engineers want, rather than take the moral high ground and put forth edicts about how people must develop systems. .Bob. Software Engineer, Ada tasking -- Bob Kitzberger Internet : rlk@telesoft.com TeleSoft uucp : ...!ucsd.ucsd.edu!telesoft!rlk 5959 Cornerstone Court West, San Diego, CA 92121-9891 (619) 457-2700 x163 ------------------------------------------------------------------------------ package body Disclaimer is separate;