Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!ukc!stl!robobar!ronald From: ronald@robobar.co.uk (Ronald S H Khoo) Newsgroups: comp.lang.perl Subject: Re: While learning PERL... a suggestion Message-ID: <1991Jan20.114635.11547@robobar.co.uk> Date: 20 Jan 91 11:46:35 GMT References: <1991Jan19.003519.23569@ux1.cso.uiuc.edu> <11115@jpl-devvax.JPL.NASA.GOV> <118879@uunet.UU.NET> Organization: Robobar Ltd., Perivale, Middx., ENGLAND. Lines: 44 rbj@uunet.UU.NET (Root Boy Jim) writes: > An easier question might be "What's missing, compared to C?" Seems like a reasonable question to me :-) > Going thru the syscalls I see trivial omissions, such as `mknod' > or `reboot' that can best be done by invoking "system", without > resorting to using syscall. One function that I need, which *can't* be gotten through either syscall or system is sbrk(0) -- especially necessary if you're running on a System V based PC Unix where the performance hits the floor as soon as you run out of real core, so it is (sigh) necessary to tune one's programs not to. [ I guess lousy VM is better than no VM at all, though. ] So guess what's the current only member of my usersub.c :-) > It is unclear whether signals are reset upon being being caught > and whether it is blocked during signal handler execution. I > believe Larry deliberately avoided answering these questions > in order to avoid system dependencies. It's the usual trade between portability of the perl script vs. more accurate access to the underlying OS I suppose ? Both aspects of perl are important. How *do* you determine which road to follow where they conflict ? > along with finer resolution alarm timers. If this is done, I hope that someone will do emulation modules for systems without it. I guess that I rate perl script portability slightly more highly. It would really get on my wick if I had to mod a perl script just because someone gratuitouly used [gs]etitimer in a program that didn't actually need it... An emulation for System V that didn't actually give you the finer resolution would save the day there. Obviously it doesn't help the apps that actually need the resolution, but there's nothing you can do about that (is there ?) [ PS Actually, I need that [gs]etitimer emulator -- does anyone have one ? I can't write it cos I ain't got BSD manuals :-( ] -- Ronald Khoo +44 81 991 1142 (O) +44 71 229 7741 (H)