ctrlaltdel - set the function of the Ctrl-Alt-Del combination
ctrlaltdel hard|soft
Based on examination of the linux/kernel/reboot.c code, it is clear that there are two supported functions that the <Ctrl-Alt-Del> sequence can perform.
hard
Immediately reboot the computer without calling sync(2) and without any other preparation. This is the default.
soft
Make the kernel send the SIGINT (interrupt) signal to the init process (this is always the process with PID 1). If this option is used, the init(8) program must support this feature. Since there are now several init(8) programs in the Linux community, please consult the documentation for the version that you are currently using.
When the command is run without any argument, it will display the current setting.
The function of ctrlaltdel is usually set in the /etc/rc.local file.
-V, --version
Display version information and exit.
-h, --help
Display help text and exit.
/etc/rc.local
init(8), systemd(1)
For bug reports, use the issue tracker at https://github.com/karelzak/util-linux/issues.
The ctrlaltdel command is part of the util-linux package which can be downloaded from Linux Kernel Archive https://www.kernel.org/pub/linux/utils/util-linux/.