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- Date: Thu, 21 Oct 93 19:32:12 -0400
- From: "Nicholas S Castellano" <entropy@terminator.rs.itd.umich.edu>
- To: sjg
- In-Reply-To: sjg@phlem.ph.kcl.ac.uk's message of Thu, 21 Oct 93 16:17:44 +0100 <9310211517.AA10128@phlem.ph.kcl.ac.uk>
- Subject: It's feedback time!
-
-
- >Ah well. Looks like there's a reason all those unix workstations have R4000
- >or Alpha processors in them then :-). I'll let you know how it works on an
- >040 early next year.
-
- Heh...well on UNIX it's a lot simpler, all the library read() does is
- call the operating system, which then does the right thing...of course
- the internals of the read() call in UNIX are probably pretty hairy
- too..
-
- Of course a faster processor doesn't hurt...but from what I hear the
- overhead difference in millions of single-byte reads() between a 68000
- and an '03 isn't as much as one would hope...
-
- >Yes, I've heard of that. Doesn't it do things like bcopy the entire
- >execution space every timeslice though. It sounds *incredibly* slow. At
- >least, there ought to be an option for >020 processors.
-
- Exactly. Sounds slow to me too. I agree, on processors where it
- isn't necessary to fake it it should be done properly.
-
- Just a guess here, but it may be possible to do a non-blocking fork on
- a 68000 for shared-text programs without copying the whole thing in
- and out. Whether anyone ever gets around to implementing any of this
- is of course still an open question ...
-
- >> What problems have you had with signals?
- >
- >The error numbers were the annoying ones. There's a list below of what
- >Ultrix defines and what MiNT defines. There's a fair amount of common
- >ground, but MiNT appears to 'double-up' its errors, ie: where Ultrix will
- >have 2 or 3 errors, MiNT has only the one, which is returned for all 2 or 3
- >cases.
- >
- >The signals are (mainly) annoying because I have problems understanding
- >the function prototype definitions in the header files :-). I think they
- >actually map quite well across to unix.
-
- Yeah they are kinda hairy...too bad cdecl doesn't decode ansi
- declarations (at least the version I have) and doesn't really deal
- with typedefs either...
-
- >The following are defined by Ultrix. I've put the MiNT error numbers in
- >brackets after the Ultrix ones. There are other MiNT codes unsupported by
- >Ultrix after this list...
- >
- >
-
- Thanks for the errno list.
-
- >(1) Should be EBUSY ?
- >(2) Should be ESPIPE ? (why PIPE ?)
- >(3) MiNT defines it to be /* invalid function number */
-
- I'll look into these, i'm not sure offhand...
-
- --entropy
-
- --
- entropy -- it's not just a good idea, it's the second law.
- Personal mail: entropy@gnu.ai.mit.edu
- MiNT library mail: entropy@terminator.rs.itd.umich.edu
-
-
-