How is the system call in Linux implemented?

Question

When I invoke a system call in user mode,how did the call get processed in OS?

Does it invoke some some executable binary or some standard library?

If yes,wh

Answer 1

A syscall is made of a special trap instruction, a syscall number and arguments.

1. The special trap instruction is used to switch from user mode to kernel mode which has unlimited privilege.
2. The syscall number and arguments are passed by register.