13: System Services
- Page ID
- 19945
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There are many operations that an application program must use the operating system to perform. Such operations include console output, keyboard input, file services (open, read, write, close, etc.), obtaining the time or date, requesting memory allocation, and many others.
Accessing system services is how the application requests that the operating system perform some specific operation (on behalf of the process). More specifically, the system call is the interface between an executing process and the operating system.
This section provides an explanation of how to use some basic system service calls. More information on additional system service calls is located in Appendix C, System Service Calls.