Program communicating with itself between executions

Question

I want to write a C program that will sample something every second (an extension to screen). I can't do it in a loop since screen waits for the program to terminate every time, and I have to access the previous sample in every execution. Is saving the value in a file really my best bet?

Answer 1

Is saving the value in a file really my best bet?

Unless you want to write some complicated client/server model communicating with another instance of the program just for the heck of it. Reading and writing a file is the preferred method.

Answer 2

You could use a named pipe (if available), which might allow the data to remain "in flight", i.e. not actually hit disk. Still, the code isn't any simpler, and hitting disk twice a second won't break the bank.

You could also use a named shared memory region (again, if available). That might result in simpler code.

You're losing some portability either way.