Hi Denys ! On 19-02-2014 15:35 Denys Vlasenko <[email protected]> wrote: >On Wed, Feb 19, 2014 at 2:48 PM, Harald Becker <[email protected]> >wrote: >> On 19-02-2014 14:31 Denys Vlasenko <[email protected]> >> wrote: >>>> # Trap CTRL-ALT-DELETE >>>> null::ctrlaltdel:/sbin/reboot >> >>>Pressing CTRL-ALT-DEL sends SIGINT signal to process 1. >>>You want to make sure it reaches it. >> >> Don't forget to set /proc/sys/kernel/ctrl-alt-del to "0" (zero) >> to enable sending SIGINT to the init process. >> >> e.g.: echo "0" >/proc/sys/kernel/ctrl-alt-del >> >> Without this most Linux kernel try an immediate reboot without >> saving buffers etc., know to fail/hang on some emulators. > >init.c does that already: > > /* Turn off rebooting via CTL-ALT-DEL - we get a > * SIGINT on CAD so we can shut things down > gracefully... */ reboot(RB_DISABLE_CAD); /* misnomer */
Outch! ... if you do this before proc is mounted and system is prepared successfully, most emulators fail and many linux systems just hang when they receive a ctrl-alt-del. The command is right (same as writing to /proc/sys/kernel/ctrl-alt-del) but time to do this is wrong. Move that behind the initial system setup, then enable ctrl-alt-del. As I had several trouble with Busybox init, I dropped that and replaced it with my own programs, so I didn't note earlier the wrong time you enable ctrl-alt-del in BB init. I do not know what's the reason for this. I just found it necessary to enable ctrl-alt-del at the right time in system setup (and not earlier). Had several kinds of trouble on system startup, when ctrl-alt-del is enabled to early and one presses ctrl-alt-del. I did never look or try to analyze this. -- Harald _______________________________________________ busybox mailing list [email protected] http://lists.busybox.net/mailman/listinfo/busybox
