What is the difference between system call and library call?

linux operating-system system-calls libraries terminology
drdot picture drdot · Apr 23, 2015 · Viewed 29k times · Source

Can someone explain the differences for these two in linux? Please go as deep as possible into each step the operating system takes.

Answer

Rahul Tripathi picture Rahul Tripathi · Apr 23, 2015

Low level kernel calls which are handled by the kernel are the system calls.

The man page says:

2 System calls (functions provided by the kernel)

3 Library calls (functions within program libraries)

A pictorial image can make it clear:

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and

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