What does the _NR number in the system call number mean? This is commonly used as a suffix.

Question

Can someone tell me what NR means? for example: #define _NR_exit

I look everywhere, but I could not find the answer.

Answer 1

This applies to Linux 0.01 (see include/unistd.h).

In kernel/system_call.sis the line:

nr_system_calls = 67

and include/linux/sched.hhas:

#define NR_TASKS 64

and include/linux/fs.hhas a whole bunch of other constants NR_xxx.

In all these cases, "nr" is explicitly used as an abbreviation for "number".

, , : " NumbeR?" .

Answer 2

_NR - .. :)