System Programming

A few illustrated reminds about linux system programming.
For complete explanations, please have a look at : https://www.enib.fr/~harrouet

Every following examples can be downloaded here :

CODE

just write ‘make’ in a terminal to compile all of them.

Hello World

Repeat

Calculate Average

Using Files ( Low Level)

Using Files ( High Level)

Exec Function

Redirections

Process and Fork

A process is a running program.
If you want to launch another process ( child ) in a running process ( parent ),
you have to use the FORK() function.
Both of them share the same code, but the memory allowed is different.
You can distinguish them with their PID ( Process ID ).

Process Dialog : Pipes

Since processes don’t share the same memory, you can use pipes to exchange datas.

Process Dialog : Socket

Sockets can be used as pipes as well.

Process Dialog : Tubes and Redirection

Threads

Threads can be seen as ‘light’ processes. Threads created in a process share the same memory.

Calc with threads