Device Drivers in perl?

deprecated has asked for the wisdom of the Perl Monks concerning the following question:

Well, after a brief but mostly thorough search of the monastery, I have found one other attempt at writing a device driver in perl.

Before I can ask for help with this, I need to give a brief explanation and perhaps some background.

Im using SunOS 5.8 ("Solaris 8") on a Sony VAIO subnote. It has a USB floppy drive which isnt quite supported by solaris, and a PCMCIA CD-ROM drive which is also not quite supported by solaris. Its onboard networking is fried, as the previous owner plugged a digital (high current) line into it and literally zapped the circuit traces on the board. So, while this is a great little critter for developing, it is 100% impossible to get data off of it (and I'm trying to use it to write a server in perl).

So the start of the solution here is a 3Com 'Megahertz' 10/100 network card, which is PCMCIA. Sun has excellent manpages and stuff, so writing the driver will be a bitch, but its not going to be fun because its C. I got to thinking last night that it might be possible to write a driver in perl, but it would have to call the C functions somewhere. Would this process be similar to the process people use to write C code for perl modules? It would be possible to extrapolate simple driver modules for perl using the manpages and whatnot. Has anyone done anything like this?

thanks
brother dep.

--
transcending "coolness" is what makes us cool.

Comment on Device Drivers in perl?

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Re: Device Drivers in perl? by Jouke (Curate) on Mar 05, 2001 at 18:11 UTC
I guess everything is possible, for example by using Inline::C. But the first thing that comes to mind is use the right tools for the job you have to do. Jouke Visser, Perl 'Adept'	[reply]
Re: Device Drivers in perl? by Malkavian (Friar) on Mar 05, 2001 at 18:17 UTC
The previous example you have seems to deal in a more 'high level' driver. In that you're dealing with an abstraction layer already (talking through other low level devices and using a protocol). Writing a device driver requires some pretty hefty usage of registers, IO addresses and interrupt control. Easy in C (well, sorta), but (as far as I know, and I'm far from a guru), a bit of a nightmare in Perl. Also, a low level device driver is a real time system, and with all the best will in the world, I'd really break a heavy sweat if anyone asked me to code true real time systems in Perl. It's just not designed for the task. Just my tuppence worth, Malk	[reply]
Re (tilly) 1: Device Drivers in perl? by tilly (Archbishop) on Mar 05, 2001 at 20:04 UTC
It is likely that your device driver will need to operate in a hard limit of a few hundred K or so of memory. In which case Perl would be simply undoable. OTOH it might be possible to call out to user space. In that case amusing things are possible. But don't count on it.	[reply]
Re: Device Drivers in perl? by deprecated (Priest) on Mar 05, 2001 at 21:29 UTC
Actually, now that I think about it, writing a device driver library for perl would be exceptionally useful for people actually having to do this horrid task in C. Imagine, being able to whip up one-liner solutions so that you could use Sun's `poke, peek,`and`probe` functions without having to write a whole damn C program. for example: `root@brak# perl -MSun::DDI -e 'probe /dev/pcmcia/*' # is muuuuuuch easier than: #include <stdio.h> #include <sunddi.h> #include <thatotherannoyingsunheaderfile.h> int main (void) { int i_will_save_you_the_agony_of_reading_c_code = 0; // ... }` [download] I'll let everyone know what I come up with after I read Sun's Writing Device Drivers today. This could be exceptionally useful. party on, brother dep. -- transcending "coolness" is what makes us cool.	[reply] [d/l] [select]
Re: Device Drivers in perl? by strredwolf (Chaplain) on Mar 06, 2001 at 03:25 UTC
Definetly possible. Heck, they have the Perl File System modules for Linux, so you can program up your own filesystem. -- $Stalag99{"URL"}="http://stalag99.keenspace.com";	[reply]