System calls Description
fork() To create a new process.
exec() To execute a new program in a process.
wait() To wait until a created process completes its execution.
exit() To exit from a process execution.
getpid() To get a process identifier of the current process.
getppid() To get parent process identifier.
nice() To bias the existing priority of a process.
brk() To increase/decrease the data segment size of a process.