COMPUTER SCIENCE AND ENGINEERING
UNIX
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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kernel mode
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superuser mode
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privileged mode
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user mode
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Detailed explanation-1: -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.
Detailed explanation-2: -The Linux kernel can send signals, for instance, when a process attempts to divide by zero it receives the SIGFPE signal. Alternatively, we can send signals in a terminal using key combinations. For instance, Ctrl+C sends SIGINT, Ctrl+S sends SIGSTOP, and Ctrl+Q sends SIGCONT.
Detailed explanation-3: -Ctrl-C (in older Unixes, DEL) sends an INT signal ("interrupt", SIGINT); by default, this causes the process to terminate. Ctrl-Z sends a TSTP signal ("terminal stop", SIGTSTP); by default, this causes the process to suspend execution.
Detailed explanation-4: -The CTRL + C is one signal in C or C++. So we can catch by signal catching technique. For this signal, the code is SIGINT (Signal for Interrupt). Here the signal is caught by signal() function.