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What do you mean by operating architecture?

    

What do you mean by operating architecture?

SYSTEM CALLS

·                                                          


           System calls provide the interface between a process and the operating system.

 

·         The purpose of system call is to request the operating system to perform some activity.

 The execution of a system call require the user process to save its current state and pass the control of the CPU to the operating system to perform some function.

 There are different system calls for performing different kinds of tasks:

 

1.       FILE MANIPULATION SYSTEM CALLS, for example: open, close, read, write, reposition etc.

2.       PROCESS CONTROL SYSTEM CALLS. For example : end, abort, load, execute, create process, terminate process, allocate and free memory, wait event, signal event.

3.       DEVICE MANAGEMENT SYSTEM CALLS . for example: read write, reposition, request device, release device attributes, set device attributes etc.

4.       INFORMATION MAINTENANCE SYSTEM CALLS. For example :get time or date, set time or date time or, get system data, set system data, get process attributes, file attributes, get device attributes etc.

5.       COMMUNICATION SYSTEM CALLS. For example :send message, receive message, create communication connection, delete communication connection, transfer status information etc.

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