[RESOLVED] How can I implement bidirectional communication between two processes?

[vincegata]

Hello,

I have two command line apps, one of them is multithreaded. I need to implement a bidirectional communication between them. Currently I can do

ProgramA 1> ProgramB

for the first programA to direct output into ProgramB, however I also need ProgramB to send messages to ProgramA.

Can you give me ideas, maybe samples, how to implement it in a easiest way. Thank you!

btw, I am on Ubuntu.

EDIT: I'd rather not to use third party libraries, Boost, etc.

[vincegata]

So, there are pipes, FIFOs, message queues, semaphores, and shared memory.

Semaphores and shared memory are probably an overkill. Pipes are unidirectional so I'd need two of those, then I can use also use FIFO or message queues. I do not have experience with any of those. What would be an easiest way? I just need two apps to exchange text messages. I would also like for debugging purposes for a program to spit the output into stdout and read from stdin if I run any of the two programs on their own.

Thank you.

[ninja9578]

I tend to use sockets.

[vincegata]

Right, also sockets. Would it be the easiest way comparing to other methods, the easiest for debugging messages and easiest for implementing?

[mlgoff]

a semaphore is not going to pass a message. It's only going to let you know the availability of a resource.

I usually use shared memory. It may be overkill in your instance (I don't know but you said it was), but it does give you flexibility should you requirements change.

[vincegata]

Shared memory & semaphores are probably the most difficult to implement, I want to use pipes or FIFO.

[treuss]

Check this post (from a long time ago). The example assumes though that your first program spawns the second one.

[vincegata]

Check this post (from a long time ago). The example assumes though that your first program spawns the second one.

thanks for the link.