In modern
computer operating systems, a
process (or
task) may
wait on another process to complete its execution. In most systems, a
parent process can create an independently executing
child process. The parent process may then issue a
wait system call, which suspends the execution of the parent process while the child executes. When the child process terminates, it returns an
exit status to the operating system, which is then returned to the waiting parent process. The parent process then resumes execution.