Re: Appendix: multithreating HOWTO ? :)
Frank Kotler <fbkotler <at> zytor.com>
2009-08-23 19:18:48 GMT
> thanks for answer, im experiment with system clone ( actualy fork i found in many manuals ) but i dont
understand Frakns last sentence
> "Well, they *told* us not to do it that way. :)", to program multiproceses with fork ? Any way is there any way
to make share memory for proceses ?
Just a "joke". I meant, using the int 80h (or syscall) interface. We're
"supposed" to use the C interface.
Like Claudio, I'm a "32-bit guy" - and I don't know how to do
multithreading even on 32-bit. But I think if you're going to use 64-bit
registers, you'll have to use 64-bit sys_call numbers, put the
parameters in regs compatible with the 64-bit ABI, and use "syscall"
instead of "int 0x80". I don't think what you're doing will work, but
I'm not equipped to try it.
You can share memory between processes by memmapping a region and
flagging it MAP_SHARED (sys_fork or even separate executables). I
*think* for threads, you'd want sys_clone, and all memory would be
shared(?). I think your issue is going to be keeping your threads from
read/writing the same memory at the same time. I'm a "single CPU guy",
too, but I think multi-CPU is going to be "even worse".
I made an example using pthread_create - not that I want to use it
either, but to see what it does for us. Easier to read the source, I'm
sure, but no, I ran it in strace. Doing a bunch of "signal related"
stuff I don't understand. I'm afraid I'm going to have to learn more
about "signals" before I can proceed with this...
For those of us who need to learn about 64-bit programming, there's a