3 ms·

So this is pretty neat. From the code we can see that: If you set the console switches of the PDP-11 to the magic number 173030 init executes "/bin/sh -" on t

So this is pretty neat. From the code we can see that: If you set the console switches of the PDP-11 to the magic number 173030 init executes "/bin/sh -" on the console tty (probably a decwriter). Otherwise it starts /etc/getty on /dev/tty0 - tty8, ttya, and ttyb. It also starts /etc/dpd ("Dpd is the 201 data phone daemon. It is designed to submit jobs to the Honeywell 6070 computer via the GRTS interface."), /usr/mel/da (???) and /usr/demo/dds (???). When user logs out it's copying the utmp entry to wtmp. I can see that the init binary is 456 bytes. It's mounting hard drives /dev/rk1-rk3 on /usr, /sys and /crp. Maybe no /etc/fstab yet. I guess /dev/rk0 had root.

voltagex_ 11y ago
>maybe no /etc/fstab yet Not in that repo https://github.com/DoctorWkt/unix-jun72/search?utf8=%E2%9C%93&q=fstab https://github.com/DoctorWkt/unix-jun72/search?utf8=%E2%9C%9... (github mirror picked at random). I'm not sure what the easiest way to find out when fstab was added would be.
- cremno 11y ago
  Reading man pages and hoping they're correct: http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/fstab.5 http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/... >The fstab file format appeared in 4.0BSD.
  - Someone 11y ago
    I would look in the git repository for Unix: https://github.com/dspinellis/unix-history-repo https://github.com/dspinellis/unix-history-repo. It isn't guaranteed to be correct, either, but should have a commit describing its addition that can be trusted slightly more. The earlier i can find there without digging deep is BSD 4.4 Lite, a mega-commit by Rodney Grimes (https://github.com/dspinellis/unix-history-repo/commit/d22731cac9fabe420b069774896e5e0ba30ee1e5#diff-ca903a47e79e99bcc3c07fbe0612f1ec https://github.com/dspinellis/unix-history-repo/commit/d2273...) Being an enormous commit, changes are that it merged in existing stuff.
    - cremno 11y ago
      The history section in this man page is correct. Relevant commits in chronological order: usr/include/fstab.h: https://github.com/dspinellis/unix-history-repo/commit/fd4f9090882927a06d5b372bd129450058f4e346 https://github.com/dspinellis/unix-history-repo/commit/fd4f9... usr/skel/etc/fstab: https://github.com/dspinellis/unix-history-repo/commit/fd4f9090882927a06d5b372bd129450058f4e346 https://github.com/dspinellis/unix-history-repo/commit/fd4f9... usr/man/man5/fstab.5: https://github.com/dspinellis/unix-history-repo/commit/8591f4b1700e44c73ec2359af971421ce0106f76 https://github.com/dspinellis/unix-history-repo/commit/8591f...
JdeBP 11y ago
It's not that magic. It's the address of the (RF disc) IPL in the "UNIX ROM". It allows the operator to bootstrap Warm UNIX into single-user mode by just pressing LOAD then START without adjusting the front panel switches. Bootstrapping Warm UNIX into multi-user mode is achieved by just toggling one front panel switch (#15) in between LOAD and START. It's all described in the accompanying boot(7) manual page.

voltagex_ 11y ago

>maybe no /etc/fstab yet Not in that repo https://github.com/DoctorWkt/unix-jun72/search?utf8=%E2%9C%93&q=fstab https://github.com/DoctorWkt/unix-jun72/search?utf8=%E2%9C%9... (github mirror picked at random). I'm not sure what the easiest way to find out when fstab was added would be.

cremno 11y ago
Reading man pages and hoping they're correct: http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/fstab.5 http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/... >The fstab file format appeared in 4.0BSD.
- Someone 11y ago
  I would look in the git repository for Unix: https://github.com/dspinellis/unix-history-repo https://github.com/dspinellis/unix-history-repo. It isn't guaranteed to be correct, either, but should have a commit describing its addition that can be trusted slightly more. The earlier i can find there without digging deep is BSD 4.4 Lite, a mega-commit by Rodney Grimes (https://github.com/dspinellis/unix-history-repo/commit/d22731cac9fabe420b069774896e5e0ba30ee1e5#diff-ca903a47e79e99bcc3c07fbe0612f1ec https://github.com/dspinellis/unix-history-repo/commit/d2273...) Being an enormous commit, changes are that it merged in existing stuff.
  - cremno 11y ago
    The history section in this man page is correct. Relevant commits in chronological order: usr/include/fstab.h: https://github.com/dspinellis/unix-history-repo/commit/fd4f9090882927a06d5b372bd129450058f4e346 https://github.com/dspinellis/unix-history-repo/commit/fd4f9... usr/skel/etc/fstab: https://github.com/dspinellis/unix-history-repo/commit/fd4f9090882927a06d5b372bd129450058f4e346 https://github.com/dspinellis/unix-history-repo/commit/fd4f9... usr/man/man5/fstab.5: https://github.com/dspinellis/unix-history-repo/commit/8591f4b1700e44c73ec2359af971421ce0106f76 https://github.com/dspinellis/unix-history-repo/commit/8591f...

JdeBP 11y ago

It's not that magic. It's the address of the (RF disc) IPL in the "UNIX ROM". It allows the operator to bootstrap Warm UNIX into single-user mode by just pressing LOAD then START without adjusting the front panel switches. Bootstrapping Warm UNIX into multi-user mode is achieved by just toggling one front panel switch (#15) in between LOAD and START. It's all described in the accompanying boot(7) manual page.