From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: fd705,41969c265865be87 X-Google-Attributes: gidfd705,public X-Google-Thread: 102b75,660f5ccab731a5a3 X-Google-Attributes: gid102b75,public X-Google-Thread: 103376,9cccf6ef6149fdaa X-Google-Attributes: gid103376,public X-Google-Thread: ff68d,660f5ccab731a5a3 X-Google-Attributes: gidff68d,public From: Chris Morgan Subject: Re: Ada Date: 2000/01/14 Message-ID: <87iu0wf2pd.fsf@think.mihalis.net>#1/1 X-Deja-AN: 572838507 Sender: cm@think.mihalis.net References: <83reu2$2soi$1@msunews.cl.msu.edu> <38615cc4.22862595@news.shuswap.net> <84dnsu$g69@nnrp1.farm.idt.net> <84drm7$ss8$1@news.rchland.ibm.com> <855lqp$t2@nnrp4.farm.idt.net> <85l4kt$e9q@nnrp1.farm.idt.net> <85nohj$n25@spool.cs.wisc.edu> Organization: Linux Hackers Unlimited X-Server-Date: 15 Jan 2000 03:12:17 GMT Newsgroups: alt.folklore.computers,comp.arch,comp.sys.unisys,comp.lang.ada Date: 2000-01-15T03:12:17+00:00 List-Id: "Andy Glew" writes: > > > If you can get C and Unix for free why do you need Ada and Ada-OS? > > Just for my own knowledge: does GNU Ada (GNATS) support a full > Ada-OS, including the real-time and multithreading constructs like > rendezvous? Do these run on stock hardware? On LINUX? Full (i.e. strict) compliance with Ada semantics needs root privilege on some OSs (e.g. Solaris last time I checked) so that your threads can get true pre-emptive multi-threading (e.g. by running in the real-time rather than time-sharing scheduling priority class). Otherwise (again on Solaris, last time I checked) there are things like threads going to the back of their queue after being pre-empted by a higher priority thread, which is incorrect for true pre-emption (it looks to the thread like it got preempted by a "sibling"). On the other hand you can even chose user-space or kernel threads. There is some advanced work on this stuff going on at FSU e.g. to make user-space threads more useful by letting another thread work when one blocks on I/O. Additionally the GNAT compiler has lots of other goodies. Check out www.gnat.com and www.gnuada.org for some nice starting points. Markus Kuhn at Cambridge has implemented a candidate Serpent (some crypto scheme) implementation in Ada, don't know how it did. The above is probably garbled (long day) hope it give you some idea. Chris -- Chris Morgan http://mihalis.net