Upgrading UNIX Sixth Edition - Revision history

Jnc: /* External links */ +'run' shell command file

2023-03-04T11:02:21Z

‎External links: +'run' shell command file

Jnc: /* Building a /45 or /70 OS binary */ link /70

2019-11-14T02:34:27Z

‎Building a /45 or /70 OS binary: link /70

Jnc: /* See also */ +1

2019-03-03T01:13:30Z

‎See also: +1

Jnc: /* See also */ add some

2019-01-29T21:48:50Z

‎See also: add some

Jnc: tweaks

2019-01-08T13:08:43Z

tweaks

Jnc: A good start

2019-01-07T22:52:08Z

A good start

New page

[[UNIX Sixth Edition]] is distributed with [[binary]] (both [[user]] [[command]]s, and the [[operating system]]) for a [[PDP-11/40]].

This makes sense, from a distribution logistics perspective; the -11/40 binary will run on any PDP-11 available at the time which will support UNIX (i.e. [[PDP-11/45]], etc), and once UNIX is up and running, it is fairly easy to produce binaries of the OS and user commands which take advantage of the extra capabilities of the /45, etc - principally [[PDP-11 Memory Management|Split I+D space]].

The [[Setting up UNIX - Sixth Edition]] document is a little thin on details for how to do the upgraded OS, however; it just says:

<pre>
In the run Shell file, the 11/45 code is commented out.
...
Since the layout of addresses in the system is somewhat peculiar, and
not directly supported by the link-editor 'ld', the 'sysfix' program
has to be run before the loaded output file can be booted.
</pre>

Not very detailed (although, to be honest, there's not a great deal of complexity). More detailed instructions are below; and if you want to know more about that "somewhat peculiar .. layout of [[address]]es in the system", see [[Unix V6 kernel memory layout]].

==Building a /45 or /70 OS binary==

To start with, do read through the 'Setting up UNIX - Sixth Edition' document to make sure everything else in it is fresh in your memory.

The aforementioned 'run' [[shell]] command [[file]] (in /usr/sys) contains the following commented-out commands which need to be run to build a /45 or /70 system (the same OS binary can be run on either type of machine, and will automatically adapt):

: as m45.s
: mv a.out m45.o
: cc sysfix.c
: mv a.out sysfix
: as data.s l.s
: ld -x -r -d a.out m45.o c.o ../lib1 ../lib2
: nm -ug
: sysfix a.out x
: mv x a.out

And that's all you need to do to build the binary for a /45; none of the other object files (in the two [[library|libraries]]) need to be touched.

('''Note''': you may need to edit the m45.s file to turn the '[[floating point]] [[hardware]] present' flag off or on. If you intend to be turning it off and on a lot, it's probably best to move it into a separate file, and prepend that to the assembly command, viz.:

: as fpon.s m45.s

or

: as fpoff.s m45.s

so you'll never have to actually edit anything.)

Here is a brief commentary on what each one does:

* as m45.s - assemble the machine-language support module; all the other modules of the OS are written in C
* mv a.out m45.o - the assembler's output file is named 'a.out' for historical reasons
* cc sysfix.c - you'll need this command in a moment
* mv a.out sysfix - the C compiler ''also'' uses 'a.out'
* as data.s l.s - the l.s file contains configuration-specific material; see the explanation below - and the 'data.s' (the order ''is'' important) is to force the information in this to go in the 'data' section (see the memory layout article)
* ld -x -r -d a.out m45.o c.o ../lib1 ../lib2 - the command to actually build the OS binary, using the system's ordinary linker/loader; the -r flag says to save the [[relocation]] information in the output file ('sysfix' will need this), the -x flag says to discard [[local]] [[symbol]]s, and only retain [[global]]s, and the -d flag forces allocation of storage for common blocks
* nm -ug - list un-defined global symbols (AKA errors)
* sysfix a.out x - magic!
* mv x a.out - it's probably better to do something like 'mv x /45unix', or something like that; since the /45 version of the OS will then be in a different file (you'll type that name in the [[bootstrap]]ping process), if you make a mistake, the /40 version is still there, and can be booted.

The configuration of the system (in terms of what device it supports, etc) are specified in two files, c.c and l.s. For novice users, these are generated by the 'mkconf' utility, but after a while you may prefer to just edit them directly. (If you want to do anything that's not supported by 'mkconf', you will have no other choice, except modifying it.)

The former provides the table which converts device numbers to the appropriate [[subroutine]]s for the OS to open, read, write etc on that [[peripheral]]. It also contains a few parameters; e.g. what device the root of the [[file system]] is on, and which device is used for [[swapping]], and where on it the swap partition is.

The latter contains [[trap]] and [[interrupt vector]]s, and an [[instruction]] to help link them to the [[device driver]] code (via an intermediary in m40.s/m45.s).

It might be a good idea to practice all the above on a UNIX V6 system running under an emulator.

==Building a /45 or /70 user command binary==

On a /45 or /70, UNIX V6 supports the use of split-I+D for user commands. The '-i' flag to the linker/loader ('ld') tells it to produce an output binary which runs in this mode. Very few commands will need this; only those that use large amounts of memory.

Also, see the commentary in the 'Setting up UNIX - Sixth Edition' regarding floating point emulation (for machines that don't have floating point hardware).

==See also==

* [[Installing UNIX Sixth Edition]]
* [[Running UNIX V6 on an -11/23]]
* [[Installing Unix v6 (PDP-11) on SIMH]]
** [[Running Unix v6 in SIMH]]
* [[Installing UNIX Sixth Edition on Ersatz-11]]

{{Nav Unix}}

[[Category: UNIX Practical Guides]]

@@ Line 71: / Line 71: @@
 ==See also==
 * [[Unix V6 kernel memory layout]]
 ** [[Unix V6 dump analysis]]

@@ Line 80: / Line 80: @@
 ** [[Running Unix v6 in SIMH]]
 * [[Installing UNIX Sixth Edition on Ersatz-11]]
 {{Nav Unix}}
 [[Category: UNIX Practical Guides]]

@@ Line 19: / Line 19: @@
 To start with, do read through the 'Setting up UNIX - Sixth Edition' document to make sure everything else in it is fresh in your memory.
-The aforementioned 'run' [[shell]] command [[file]] (in /usr/sys) contains the following commented-out commands which need to be run to build a /45 or /70 system (the same OS binary can be run on either type of machine, and will automatically adapt):
+The aforementioned 'run' [[shell]] command [[file]] (in /usr/sys) contains the following commented-out commands which need to be run to build a /45 or [[PDP-11/70|/70]] system (the same OS binary can be run on either type of machine, and will automatically adapt):
 : as m45.s

@@ Line 71: / Line 71: @@
 ==See also==
 * [[Installing UNIX Sixth Edition]]
 * [[Running UNIX V6 on an -11/23]]
 * [[Installing Unix v6 (PDP-11) on SIMH]]

@@ Line 1: / Line 1: @@
 [[UNIX Sixth Edition]] is distributed with [[binary]] (both [[user]] [[command]]s, and the [[operating system]]) for a [[PDP-11/40]].
-This makes sense, from a distribution logistics perspective; the -11/40 binary will run on any PDP-11 available at the time which will support UNIX (i.e. [[PDP-11/45]], etc), and once UNIX is up and running, it is fairly easy to produce binaries of the OS and user commands which take advantage of the extra capabilities of the /45, etc - principally [[PDP-11 Memory Management|Split I+D space]].
+This makes sense, from a distribution logistics perspective; the -11/40 binaries will run on any PDP-11 available at the time which would support UNIX (i.e. [[PDP-11/45]], etc), and once UNIX is up and running, it is fairly easy to produce binaries of the OS and user commands which take advantage of the extra capabilities of the /45, etc - principally [[PDP-11 Memory Management|Split I+D space]].
 The [[Setting up UNIX - Sixth Edition]] document is a little thin on details for how to do the upgraded OS, however; it just says:
@@ Line 13: / Line 13: @@
 </pre>
-Not very detailed (although, to be honest, there's not a great deal of complexity). More detailed instructions are below; and if you want to know more about that "somewhat peculiar .. layout of [[address]]es in the system", see [[Unix V6 kernel memory layout]].
+Not very detailed (although, to be honest, there's not a great deal of complexity). More detailed instructions are below; and if you want to know more about that "somewhat peculiar .. layout of [[address]]es in the system", see the page [[Unix V6 kernel memory layout]].
 ==Building a /45 or /70 OS binary==
@@ Line 31: / Line 31: @@
 : mv x a.out
-And that's all you need to do to build the binary for a /45; none of the other object files (in the two [[library|libraries]]) need to be touched.
+And that's all you need to do to build the OS binary for a /45; none of the other object files (in the two [[library|libraries]]) need to be touched.
-('''Note''': you may need to edit the m45.s file to turn the '[[floating point]] [[hardware]] present' flag off or on. If you intend to be turning it off and on a lot, it's probably best to move it into a separate file, and prepend that to the assembly command, viz.:
+('''Note''': you may need to edit the m45.s file to turn the '[[floating point]] [[hardware]] present' flag off or on. If you intend to be turning it off and on a lot, it's probably best to move it into a separate file, and prepend that to m45.s in the assembly command, viz.:
 : as fpon.s m45.s
@@ Line 43: / Line 43: @@
 so you'll never have to actually edit anything.)
-Here is a brief commentary on what each one does:
+Here is a brief commentary on what each command does:
-* as m45.s - assemble the machine-language support module; all the other modules of the OS are written in C
+* as m45.s - assemble the machine-language support module; all the other modules of the OS are written in [[C programming language|C]]
 * mv a.out m45.o - the assembler's output file is named 'a.out' for historical reasons
 * cc sysfix.c - you'll need this command in a moment
 * mv a.out sysfix - the C compiler ''also'' uses 'a.out'
 * as data.s l.s - the l.s file contains configuration-specific material; see the explanation below - and the 'data.s' (the order ''is'' important) is to force the information in this to go in the 'data' section (see the memory layout article)
-* ld -x -r -d a.out m45.o c.o ../lib1 ../lib2 - the command to actually build the OS binary, using the system's ordinary linker/loader; the -r flag says to save the [[relocation]] information in the output file ('sysfix' will need this), the -x flag says to discard [[local]] [[symbol]]s, and only retain [[global]]s, and the -d flag forces allocation of storage for common blocks
+* ld -x -r -d a.out m45.o c.o ../lib1 ../lib2 - the command to actually build the OS binary, using the system's ordinary linker/loader; the -r flag says to save the [[relocation]] information in the output file ('sysfix' will need this), the -x flag says to discard [[local]] [[symbol]]s, and only retain [[global]]s, and the -d flag forces allocation of storage for [[common block]]s
 * nm -ug - list un-defined global symbols (AKA errors)
 * sysfix a.out x - magic!
-* mv x a.out - it's probably better to do something like 'mv x /45unix', or something like that; since the /45 version of the OS will then be in a different file (you'll type that name in the [[bootstrap]]ping process), if you make a mistake, the /40 version is still there, and can be booted.
+* mv x a.out - it's probably better to do something like 'mv x /45unix', or something like that; since the /45 version of the OS will then be in a different file (you'll type that name in the [[bootstrap]]ping process), if you make a mistake, the /40 version is still there, and can be booted
-The configuration of the system (in terms of what device it supports, etc) are specified in two files, c.c and l.s. For novice users, these are generated by the 'mkconf' utility, but after a while you may prefer to just edit them directly. (If you want to do anything that's not supported by 'mkconf', you will have no other choice, except modifying it.)
+The configuration of the system (in terms of what [[peripheral|devices]] it supports, etc) are specified in two files, 'c.c' and 'l.s'. For novice users, these are generated by the 'mkconf' utility, but after a while you may prefer to just edit them directly. (If you want to do anything that's not supported by 'mkconf', you will have no other choice, other than modifying it.)
-The former provides the table which converts device numbers to the appropriate [[subroutine]]s for the OS to open, read, write etc on that [[peripheral]]. It also contains a few parameters; e.g. what device the root of the [[file system]] is on, and which device is used for [[swapping]], and where on it the swap partition is.
+The former provides the table which converts device numbers to the appropriate [[subroutine]]s for the OS to open, read, write etc on that device. It also contains a few parameters; e.g. what device the root of the [[file system]] is on, and which device is used for [[swapping]], and where on it the swap partition is.
-The latter contains [[trap]] and [[interrupt vector]]s, and an [[instruction]] to help link them to the [[device driver]] code (via an intermediary in m40.s/m45.s).
+The latter contains [[trap]] and [[interrupt vector]]s, and an [[instruction]] (per vector) to help link them to the [[device driver]] code (via some intermediary code in m40.s/m45.s).
 It might be a good idea to practice all the above on a UNIX V6 system running under an emulator.