System Calls: The OS API
A system call is a programmatic way for a program to request a service from the kernel.
Types of System Calls
| Category | Examples | Purpose |
|---|---|---|
| Process Control | fork(), exec(), exit() | Create, run, terminate processes |
| File Management | open(), read(), write(), close() | File operations |
| Device Management | ioctl(), read(), write() | Device I/O |
| Information | getpid(), alarm(), sleep() | System information |
| Communication | pipe(), shmget(), mmap() | Inter-process communication |