Difference Between fork() and vfork()

In this post, we will understand the difference between system calls fork and vfork −

The ‘fork’ system call

• In this system call, the child and parent process have separate memory spaces.

• The child and parent process are executed simultaneously.

• This call uses the copy-on-write as alternative.

• Child process doesn’t have the ability to suspend execution of the parent process in this system call.

• The page of one process doesn’t get affected by the page of other process.

• It is more frequently used.

• No address space is wasted.

• If the child process alters the page in the address space, it is not visible to the parent process.

The ‘vfork’ system call

• In this system call, the parent process and child process share the same address space.

• Once the child process has been executed, the parent process begins the execution.

• This system call doesn’t use copy-on-write technique.

• The child process suspends the execution of the parent process in this system call.

• The page of one process gets affected by the page of another process.

• It is less frequently used.

• No address space is wasted.

• If the child process alters the page in the address space, it can be seen by the parent process.