> I'm quite sure that in original Berkeley Unix, as on the VAX 11/780, halt > was an immediate halt of the CPU without any process cleanup or file system > umounting or anything. Early SunOS (pre-Solaris) was like this, too. >The SunOS 4.1.2 man page for halt says NAME halt - stop the processor SYNOPSIS /usr/etc/halt [ -oqy ] DESCRIPTION halt writes out any information pending to the disks and then stops the processor. halt normally logs the system shutdown to the system log daemon, syslogd(8), and places a shutdown record in the login accounting file Ivar/admlwtmp. These actions are inhibited if the -0 or -q options are present. The BSD 4.3 (that ran on VAXen) man pages say largely similar things: https://www.freebsd.org/cgi/man.cgi?query=halt&apropos=0&sektion=0&manpath=4.3BSD+Reno&arch=default&format=html Everything is somewhere on the net :-) P.
On Sun, Jun 14, 2020 at 6:19 PM Pete Biggs <pete at biggs.org.uk> wrote:> > > I'm quite sure that in original Berkeley Unix, as on the VAX 11/780, halt > > was an immediate halt of the CPU without any process cleanup or file > system > > umounting or anything. Early SunOS (pre-Solaris) was like this, too. > > > The SunOS 4.1.2 man page for halt says > > NAME > halt - stop the processor > SYNOPSIS > /usr/etc/halt [ -oqy ] > DESCRIPTION > halt writes out any information pending to the disks and then > stops the processor. > halt normally logs the system shutdown to the system log > daemon, syslogd(8), and places a shutdown record in the > login accounting file Ivar/admlwtmp. > These actions are inhibited if the -0 or -q options are present. > > The BSD 4.3 (that ran on VAXen) man pages say largely similar things: > > > https://www.freebsd.org/cgi/man.cgi?query=halt&apropos=0&sektion=0&manpath=4.3BSD+Reno&arch=default&format=html > >ok, so it does a sync then hard halts, but it doesn't gracefully exit services, or unmount file systems. -- -john r pierce recycling used bits in santa cruz
Working with different Linux Distributions makes the life harder. So far I have found out that 'poweroff' & 'reboot' has the same behaviour on Linux/Unix/BSDs. Best Regards, Strahil Nikolov ?? 15 ??? 2020 ?. 5:22:28 GMT+03:00, John Pierce <jhn.pierce at gmail.com> ??????:>On Sun, Jun 14, 2020 at 6:19 PM Pete Biggs <pete at biggs.org.uk> wrote: > >> >> > I'm quite sure that in original Berkeley Unix, as on the VAX >11/780, halt >> > was an immediate halt of the CPU without any process cleanup or >file >> system >> > umounting or anything. Early SunOS (pre-Solaris) was like this, >too. >> > >> The SunOS 4.1.2 man page for halt says >> >> NAME >> halt - stop the processor >> SYNOPSIS >> /usr/etc/halt [ -oqy ] >> DESCRIPTION >> halt writes out any information pending to the disks and then >> stops the processor. >> halt normally logs the system shutdown to the system log >> daemon, syslogd(8), and places a shutdown record in the >> login accounting file Ivar/admlwtmp. >> These actions are inhibited if the -0 or -q options are >present. >> >> The BSD 4.3 (that ran on VAXen) man pages say largely similar things: >> >> >> >https://www.freebsd.org/cgi/man.cgi?query=halt&apropos=0&sektion=0&manpath=4.3BSD+Reno&arch=default&format=html >> >> >ok, so it does a sync then hard halts, but it doesn't gracefully exit >services, or unmount file systems.