POSIX Capabilities Part 3 - CAP_SYS_BOOT - Allow Non-root user to reboot

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Linux provide 'reboot' api to allow user to perform a reboot from Linux Code.

#include <unistd.h>
#include <sys/reboot.h>

int reboot(int cmd);

reboot(RB_AUTOBOOT); will print the message "Restarting system." and reboot will be performed.

If a non-root user tries to perform this, it will fail with permission denied error.


Now, if we run cap_sys_boot_test, the system will reboot when run with non-root user.

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