*FUNCTIONS

• open()

• close()

• write()

• read()

• malloc()

• free()

• free()

• perror()

• strerror()

• access()

• dup()

• dup2()

• execve()

• exit()

• fork()

• pipe()

• unlink()

• wait()

• waitpid()

*process

• When a program is under execution, then it is known as a process. Basically, a process allows you to execute all the relevant tasks in a program. In this, the operating system helps you to design, plan, schedule, and terminate the processes used by the CPU.

*Differences Between Process and Thread

• **Process means a program is in execution, whereas thread means a segment of a process.**
• **A Process is not Lightweight, whereas Threads are Lightweight.**
• **A Process takes more time to terminate, and the thread takes less time to terminate.**
• **Process takes more time for creation, whereas Thread takes less time for creation.**
• **Process likely takes more time for context switching whereas as Threads takes less time for context switching.**
• **A Process is mostly isolated, whereas Threads share memory.**
• **Process does not share data, and Threads share data with each other.**