GATE PYQ

System Call

Q21.
Fork is

Q22.
Which of the following commands or sequences of commands will rename a file x to file y in a Unix system ? I. mv y, x II. mv x, y III. cp y, x (rm x) IV. cp x, y (rm x)

Q23.
When an interrupt occurs, an operating system

Q24.
System calls are usually invoked by using

Q25.
A user level process in Unix traps the signal sent on a Ctrl-C input, and has a signal handling routine that saves appropriate files before terminating the process. When a Ctrl-C input is given to this process, what is the mode in which the signal handling routine executes?