process communication

andyar85 · 01-12-2008, 02:29 PM

Hy

I have a situation, meaning I have 2 processes going on and I want the two to communicate between each other.
the thing is in the first one I have an array like int r[100], and i want to use this variable in the second process. I thought pipe is simple but it seems I got something wrong, cause I get a lot of errors. probably is my mistake. Also I have to syncronize them with semaphores,and that's a little tricky

Anyway if someone can help me and give me a hint on how to do this I'd be very graceful

Uncle_Theodore · 01-12-2008, 02:43 PM

There are scores of excellent IPC tutorials on the web. To name a few
http://www.ecst.csuchico.edu/~beej/guide/ipc/ Beej's Guide
http://www.tldp.org/LDP/lpg/node21.h...00000000000000 Linux Programmer's Guide
http://www.cs.cf.ac.uk/Dave/C/node27.html Some dude's course notes...

andyar85 · 01-13-2008, 03:48 AM

the thing is I have 2 separate child processes,not a child parent issue and I want to send form the first process an array that the second can use

Uncle_Theodore · 01-13-2008, 08:07 AM

You don't need any parental relationships between processes to use the IPC mechanisms. If it's so in the examples above, it was done just to simplify explanations. Both processes should know the same key, then they can share memory, use message queues and semaphores. You just need to figure out a way for your processes to know the same key (pass it as a command-line argument or just use ftok on the same directory/file). Or, just get your shared memory and stuff in the common parent. IPC things are fork()-safe, you might say...

sundialsvcs · 01-13-2008, 07:02 PM

Please, start by reading the IPC-tutorials listed. Much will become clear.