From: treese@crl.dec.com
Newsgroups: comp.unix.ultrix,news.answers
Subject: comp.unix.ultrix Frequently Asked Questions
Summary: This posting contains a list of Frequently Asked Questions
	(and their answers) about the ULTRIX operating system from
	Digital Equipment Corporation.
Date: 25 Jul 92 21:28:29 GMT
Expires: Mon, 7 Sep 1992 21:28:26 GMT
Followup-To: comp.unix.ultrix
Organization: DEC Cambridge Research Lab
Supersedes: <ultrix-faq_708150621@crl.dec.com>
Version: 1.3
Last-Modified: 6 May 1992
Archive-Name: ultrix-faq

This FAQ is available in the following archive sites, in the file
/pub/DEC/ultrix-faq.txt.

	gatekeeper.dec.com
	crl.dec.com
	decuac.dec.com

It can also be obtained by sending mail to ftpmail@pa.dec.com with the
following lines:
	connect
	get /pub/DEC/ultrix-faq.txt

If the location of a file in an archive is not specifically mentioned
below, it is in /pub/DEC on the above machines.

To make suggestions for changes or additions to this Frequently Asked
Questions list, send mail to ultrix-faq@crl.dec.com.  Answers are
especially appreciated.

An archive of recent postings to comp.unix.ultrix can be found via
anonymous FTP on ftp.cc.rochester.edu in /pub/usenet/comp.unix.ultrix.
Thanks to folks at the University of Rochester for providing this
service.

Some general notes:

When used alone, the word "DECstation" is used to mean any of the
DECstations or DECsystems that use MIPS RISC processors.

Unless otherwise specified, these answers refer to ULTRIX 4.2, which is
the current release of ULTRIX.

Many people have contributed to this list, directly or indirectly.  In
some cases, an answer has been adapted from one or more postings on the
comp.unix.ultrix newsgroup.  Our thanks to all of those who post answers.

This posting is not an official statement from Digital Equipment Corporation.


Software
======================================================
1. How do I play music CDs on DEC CD-ROM drives?
2. Why does dxpsview sometimes crash with an X error? **NEW**
3. How do I compile perl on RISC/ULTRIX?
4. Is it possible to run the newer 4.3 BSD syslogd on ULTRIX?
5. Where can I get a T-shell (tcsh) that works on ULTRIX 4.2? **CHANGED**
6. How do I build gdb on RISC/ULTRIX?
7. Why doesn't "talk" work between DECstations and other machines? **NEW**

Installation
======================================================
8. How do I copy a setld(8) tape?
9. How do I copy a CDROM installation kit to TK50?

Network
======================================================
10. What does the message "named: accept: Too many open files" in syslog mean,
	and how can I fix it?
11. Why don't packet-filter applications like "tcpdump" or CAP work? **CHANGED**
12. OK, I've done all that and CAP still doesn't run.
13. I want to run the "screend" program but I get "Operation not supported
	on socket".
14. I want to use screend but I'm not sure how to set up the
	/etc/screend.conf configuration file.
15. Why can't ULTRIX 4.2 mount NFS filesystems that could be mounted with
        ULTRIX 4.1?
16. How do I change the IP address of a diskless client?
17. Is ONC RPC (formerly "Sun RPC") supported under ULTRIX - and what should I
	do to port my existing applications that rely on it? **NEW**
18. How can I disable forwarding of IP packets on an ULTRIX system with two
	network interfaces? **NEW**

Disk
======================================================
19. Why doesn't ULTRIX 4.1 work with disks bigger than 1.2GBytes?
20. Where can I get a disktab entry for the XXX disk?

Programming
======================================================
21. What does "unaligned access" mean, and how can I fix it?

Printers
======================================================
22. Where can I get a printcap entry for the XXX printer?

Graphics
======================================================
23. Why does the X server use so much memory?
24. How can I build an X11R5 server for an ULTRIX 4.1 machine?
25. How do I change or get rid of the Digital logo on the login screen of 
	my workstation?
26. How do I run MIT X11 Software?
27. How do I build X software that I got from the net?
28. Why do some applications run slowly on the DECstation PX and PXG
	displays?

Hardware
======================================================
29. What are the pinouts of the MMJ jacks on the back of various DECstations
	and VAXstations?
30. How do I set the SCSI ID on an RZ25? 
31. How can I get detailed information on the TURBOchannel? **CHANGED**
32. Can I mix 8-Megabyte and 32-Megabyte boards in the DECstation 5000/xxx
	family? **NEW**
33. How can I find out which type of DECstation 5000 I have? **NEW**

Miscellaneous
======================================================
34. What is the floating-point number representation on ULTRIX?
35. If the console is a graphics device, can it be used as a terminal for
	full-screen applications?
36. How do I read a tar image from a TK50 tape if my only TK50 is on a VMS
	machine?
37. Where can I get free source code for interesting programs on ULTRIX?
38. Where can I get technical information on the DECstation family of machines?
39. Where can I get performance information about DECstations? **CHANGED**
40. Why can't I submit a bug report by electronic mail?
41. How do I send mail to Digital employees?
42. How do I get a list of available patches for my release of Ultrix?
43. How can I get files available by anonymous FTP if I'm not connected
	to the Internet?

==============================================
1. How do I play music CDs on DEC CD-ROM drives?

Music CDs can be played through a speaker jack on RRD42 CD-ROM drives,
which is the one contained in the DECstation 5000/{120,125} box.

There are two different programs: A command line version and a
Motif-based version. Both can be found in:

	gatekeeper.dec.com or decuac.dec.com
	in /pub/DEC:
			cdp.c[.Z]		/* command line version */
			xcd_source.tar.Z	/* Motif version. */

Neither of these programs is supported by Digital.

==============================================
2. Why does dxpsview sometimes crash with an X error? **NEW**

dxpsview will often behave better if the "Watch Progress" item is selected
from the Options menu.  You can use the following resource in your
.Xdefaults file:

DPSViewer*watchProgress:		om

to make this the default behavior.

Some have reported that disabling the use of PostScript comments also helps:

DPSViewer*useComments:			off


==============================================
3. How do I compile perl on RISC/ULTRIX?

The following is valid for perl 4.0, patchlevel 10.  They will probably
change in patchlevel 19.

The biggest trick in compiling perl on RISC/ULTRIX is fixing its
notion of "volatile".  To do this, when Configure stops and asks you
if you want to edit config.sh, do so. Search for the word "volatile"
and change the "define" on that line to "undef".

On machines with a relatively small amount of memory, you may not want
to use -O on eval.c, since the compiler can end up taking a long time
to compile that file.

If the source directory is NFS-mounted, it is usually the case that you
will see the message

   io/fs..........FAILED on test 18

This is harmless and can be ignored.

For patchlevel 19, you can ignore the comments above about "volatile".

==============================================
4. Is it possible to run the newer 4.3 BSD syslogd on ULTRIX?

A version of the 4.3BSD syslog library and daemon that detects either
4.2bsd-compatible clients (which is what the Ultrix libc.a will help
you create) or 4.3bsd-compatible clients, which are more flexible, is
available by anonymous FTP from gatekeeper.dec.com in
/pub/DEC/jtkohl-syslog.shar.

Another version that supports regular expressions in syslog.conf is available
from decuac.dec.com, in /pub/DEC/syslog43.urc.tar.Z

==============================================
5. Where can I get a T-shell (tcsh) that works on ULTRIX 4.2? **CHANGED**

Versions of tcsh later than 6.01 run on ULTRIX 4.2.  The latest
version the FAQ editor knows is 6.02, available by anonymous FTP from
tesla.ee.cornell.edu. You do not need csh sources for this version of
tcsh.

==============================================
6. How do I build gdb on RISC/ULTRIX?

To build gdb, you will also need to install the GNU make.

For gdb 4.0 and later: 
- unpack the tar file
- cd <tar-root>
- ./configure +subdirs decstation
- cd H-decstation/T-decstation
- gnumake

This will build the gdb binary in
<tar-root>/gdb/H-decstation/T-decstation/gdb

Install this binary in the location of your choice (e.g. /usr/local/bin)

==============================================
7. Why doesn't "talk" work between DECstations and other machines? **NEW**

The original Berkeley talk protocol did not use network byte order, so
machines with different byte order could not talk to each other.  This
was fixed in 4.3BSD, and in recent versions of ULTRIX.  Some vendors
have not fixed their software.  The 4.3BSD talk software is available
from many FTP archive sites.



==============================================
8. How do I copy a setld(8) tape?

First, a few words about the format of a setld tape.

Tapes used by setld(8) consist of a number of tape files that contain the
product subsets, installation control files and other stuff.  The fourth
file on the tape is an uncompressed tar(1) archive of the inventory files
(.inv), subset control programs (.scp) and control information (.ctrl).
There is also a file that lists the subsets, their sizes and checksums
(.image).  The tapes files after the 4th are the subset files.  They may or
may not be compressed.  They will have a block size of 10 KB.  The order of
lines in the .image file is the order of subset on the tape, with the
classic exception.

There are two flavors of tapes; Layered product tapes and ULTRIX
distribution tapes.  The first three files on layered product tapes will
typically be space holders and only one 10 KB file.  Distribution tapes use
the first three files for other things.  The 3rd of these files is dump(8)
image of the root file system.  The block size of this file will be 10 KB.
In the .image file for the distribution it would be listed ROOT:

	44419 12720 ROOT
	01690 12080 UDTBASE420
	47187 14340 UDTBIN420
	etc...

So, on this distribution tape ROOT is 3rd, the installation control
archive (INSTCTRL) is 4th, UDTBASE420 is 5th and so on.

The first two files are a primary and secondary boot program.  Whether
the 2nd is necessary depends on system architecture.  The MIPS-based
systems typically only use the first boot file; the VAX uses both.
The block size of the first boot program is 512 bytes.

Copying a setld tape

Use dd(1) to copy each tape file using the appropriate block size.  When you
run out of tape input files you're done.  For example, if you are using
two tape drives:

	   dd bs=512   if=/dev/nrmt0h of=/dev/nrmt1h
	   dd bs=10240 if=/dev/nrmt0h of=/dev/nrmt1h
	   dd bs=10240 if=/dev/nrmt0h of=/dev/nrmt1h
	   ...
	   mt -f /dev/nrmt0h rew
	   mt -f /dev/nrmt1h rew

==============================================
9. How do I copy a CDROM installation kit to TK50?

The two shell shell scripts below can be used to duplicate CDROM or disk
layered product distributions (note: not the base system) onto a TK50.
They are not supported by Digital.

--------------------------cut here--------------------------------------------
#!/bin/sh5
# cdrom_kitcap
# This script is based on one from "Guide for Preparing Software for
# Distribution" (but this one really works).  This script prepares the
# /etc/kitcap file which is needed by the gentapes script to create,
# in this specific case, a copy of cdrom software (layered product only)
# to TK50...
# note: this script uses tmp space, insure $TMPDIR is pointing to a file
# system with enough space to copy files...
# Original author:   John R. Frandsen, Digital Equipment Corporation

TMPDIR=/usr/tmp
KITCAP=$TMPDIR/kitcap
CURVOL=1

BINDIR=`pwd`

touch $TMPDIR/space
tar cf $TMPDIR/SPACE $TMPDIR/space

cd instctrl

I=`expr *.image : '\(.*\).image'`
echo "Your product code is $I"

tar cf $TMPDIR/INSTCTRL *

echo "${I}TK:$TMPDIR:SPACE:SPACE:SPACE:INSTCTRL:\\" >> $KITCAP

for S in `awk '{print $3}' *.image`
do
	[ $S = ROOT ] && continue
	. $S.ctrl
	set -- `(IFS=:;echo $MTLOC)`
	VOL=$1
	LOC=$2
	[ $VOL -ne $CURVOL ] &&
	{
		echo ":%%$VOL		CURVOL=$VOL" >> $KITCAP
	}
	echo ":$S\\" >> $KITCAP
	cp $BINDIR/$S $TMPDIR
done
echo >> $KITCAP

mv $TMPDIR/kitcap /etc
cd $BINDIR

--------------------------cut here--------------------------------------------
#!/bin/sh5
# disk_kitcap
# This script is based on one from "Guide for Preparing Software for
# Distribution" (but this one really works).  This script prepares the
# /etc/kitcap file which is needed by the gentapes script to create,
# in this specific case, a copy of disk software (layered product only)
# to TK50...
# Original author:   John R. Frandsen, Digital Equipment Corporation
 

KITCAP=/tmp/kitcap
CURVOL=1

touch space
tar cf SPACE space

cd instctrl

I=`expr *.image : '\(.*\).image'`
echo "Your product code is $I"
cp $I.image ..

tar cf ../INSTCTRL *

cd ..

echo "${I}TK:`pwd`:SPACE:SPACE:SPACE:INSTCTRL:\\" >> $KITCAP

cd instctrl

for S in `awk '{print $3}' *.image`
do
	[ $S = ROOT ] && continue
	. $S.ctrl
	set -- `(IFS=:;echo $MTLOC)`
	VOL=$1
	LOC=$2
	[ $VOL -ne $CURVOL ] &&
	{
		echo ":%%$VOL		CURVOL=$VOL" >> $KITCAP
	}
	echo ":$S\\" >> $KITCAP
done
echo >> $KITCAP

mv /tmp/kitcap /etc
    
#----------------------------------------------------------------------------


==============================================
10. What does the message "named: accept: Too many open files" in syslog mean,
	and how can I fix it?

There is a bug in the ULTRIX version of named that causes it to run
out of file descriptors when it does too many zone transfers.  A
somewhat different version of named that does not have this problem
can be found in cra-bind.tar.Z.  This version cannot use Kerberos for
server-server authentication, as the ULTRIX version can.  It does
support Hesiod data and queries.  It is not supported by Digital,
although it is in active use on Digital's Internet machines.



==============================================
11. Why don't packet-filter applications like "tcpdump" or CAP work? **CHANGED**

Probably because you have not configured the packet filter into
the kernel.  The default kernel configurations do NOT include the
packet filter.  See "man 4 packetfilter" for full details, but basically
the process involves

	editing your kernel configuration file
		add "options PACKETFILTER"
		add "pseudo-device packetfilter"
	rebuilding your kernel
	installing the new kernel
	booting the new kernel
	"cd /dev; MAKEDEV pfilt" to create the required entries

You might also want to add the following lines to /etc/rc.local:
[ -f /usr/etc/pfconfig ] && {
        /usr/etc/pfconfig +p +c -a 2>&1 & echo -n ' pfconfig'   >/dev/console
}

This allows you to use promiscuous-mode applications, such as "tcpdump"
or "nfswatch".  Note that the '-a' option to pfconfig allows any user to
spy on the network.  If it is omitted, only root may do so.

There are also some patches for ULTRIX 4.2 and 4.2A for the
packetfilter code.  Call Digital's Customer Support if you need them.
The official description of the patches is below; here is some
background information.

Although not mentioned in the description, these patches should also
make Ultrix more forgiving of certain incorrect 802.3 packets.  Such
packets are sent by some 3rd-party implementations.  I don't think
this will fix the problem in every case, since some Digital Ethernet
interfaces filter out "bad" 802.3 packets in hardware.  The patches
should work for DECstations and most DECsystems.

Note that if you install these patches and you have been running CAP,
you should recompile CAP after removing the definition for ULT42PFBUG
from the Configure script.  The ULT42PFBUG patch to CAP will not work
once the kernel has been patched.  You should also *stop* doing

	ifconfig ln0 copyall

once you install the patches.

If you have been using tcpdump, nfswatch, or a similar monitoring
program on an FDDI network, installing these patches will probably
make that not work.  You will still be able to use tcpdump on an
Ethernet, of course.  The reason for this is that tcpdump only worked
on FDDI networks because of the bug that is fixed by these patches.

These patches are available for Ultrix 4.2 and 4.2A, and for both RISC
and VAX.  They must not be applied to previous versions of Ultrix.

Finally, note you must install new versions of BOTH net_common.o
and pfilt.o; you cannot just install one of the files.

/sys/{MIPS,VAX}/BINARY/net_common.o      
/sys/{MIPS,VAX}/BINARY/pfilt.o
-----------------------------------          
			              (v4.2 RISC & VAX, v4.2a RISC)

Listed are problem resolved by these 2 patches:

1. PACKET FILTER FAILS TO RECEIVE UNICASTS TO LOCAL HOST

The packet filter mechanism is supposed to allow a user application
to receive packets that are sent to the local host, if no other
protocol in the kernel wants to use the packet.  This worked fine
in Ultrix 4.0 and 4.1, but in Ultrix 4.2 it is broken.

Apparently, setting "copyall" with ifconfig is a workaround, but
this is an EXTREMELY inefficient workaround, and requires users
to reconfigure their systems as super-user.

2. PACKET FILTER IOCTL EIOCDEVP RETURNS WRONG MTU VALUE

A change was made to increase the size for ethernet packets
from 1500 bytes to 1514 bytes which is the MAX size for the ethernet.
This will allow 1500 bytes for the message and 14 bytes for the header.

Also corrected the value returned in endevp.end_MTU by the EIOCDEVP ioctl.

3. 802.3/802.2 PACKETS NOT PROPERLY DELIVERED TO PACKET FILTER

The packet filter is defined, in its manual page, to provide packets
to user applications exactly as those packets appear on the network.
The current kernel code mangles the headers of 802.2 encapsulations
of Ethernet packets, causing several popular applications to fail.


==============================================
12. OK, I've done all that and CAP still doesn't run.

[See the previous topic for information on relevant patches for ULTRIX.]

There are several bugs in the Ultrix 4.2 packet filter mechanism, both
of which affect CAP.  The details are complex, but you can solve one
of them by doing (as super-user, probably from /etc/rc.local)

	/etc/ifconfig ln0 copyall

(substitute whatever interface type you are using for "ln0").  The
other bug, which apparently only affects CAP when "Phase 2" is in use,
requires a patch to CAP.  CAP patches are available from a number of
archive sites, including gatekeeper.dec.com: in the directory named

	/pub/net/appletalk/cap/cap.patches

Another problem you may have is that some Ethernet interfaces sold for
the Macintosh occasionally send incorrect 802.3 packet headers.  (The
bug is that they send a packet whose length does not match the value
provided in the 802.3 header's length field.  Ultrix 4.2, as well as
some of Digital's Ethernet interface hardware, is strict about
checking 802.3 header, and does not accept these packets.)  As of this
writing, a patch is not yet available and there is no workaround.  If
you can, you should try to get the vendor of the nonconforming
interface to provide a solution.

Once you have obtained an up-to-date, fully patched copy of CAP 6.0,
the Configure script does not automatically switch on the workaround
code; you must manually edit the m4.setup file to turn the workaround
code on.


==============================================
13. I want to run the "screend" program but I get "Operation not supported
	on socket".

By default, support for screend is not configured into the Ultrix 4.2
kernel, and the documentation for this is missing.  Edit your kernel
configuration file to include the line:

	pseudo-device   gwscreen

and rebuild your kernel (i.e., run /etc/config, then change to the
right directory and do "make depend" and then "make").  Install the
new kernel and reboot the system.

==============================================
14. I want to use screend but I'm not sure how to set up the
	/etc/screend.conf configuration file.

Get a copy of NSL Network Note NN-16, "Using screend to Implement
IP/TCP Security Policies".  Send mail with "Subject: help" for
information on how to order this, or just "Subject: send postscript
nn-16" if you want to receive the PostScript file via return mail to
	nsl-techreports@pa.dec.com
     or ...!uunet!decwrl!nsl-techreports

==============================================
15. Why can't ULTRIX 4.2 mount NFS filesystems that could be mounted with
        ULTRIX 4.1?

The version of SUN RPC shipped with ULTRIX V4.2 supports up to 32
groups per user, whereas previous versions supported 8 groups per
user.  Users that are members of more than 8 groups cannot NFS mount
file systems from NFS servers using the version of SUN RPC that only
supports 8 groups.

The error message  that nfs_mount will give you if you are in too many
groups will look like this:

nfs_mount: crltrx:/usr/local server not responding: RPC: Authentication error;
why = Invalid client credential
nfs_mount: access denied for crltrx:/usr/local

The workaround is to reduce the number of groups you are a member of
to eight or less to make NFS mounts work again.  In particular, you should
check the number of groups that "root" is in.


==============================================
16. How do I change the IP address of a diskless client?

To change the IP address of a diskless client, first change it in
whatever hosts database you use (BIND, /etc/hosts, or YP).  There is
also a file in the client's /etc directory called netblk.c.  It looks like
this:

#include <sas/mop.h>
struct netblk   nblk={
"server",
0x100b002a, "client", 0x100b003e, 0x100b00ff, 0xffffff00,
0,
5,
0,
0,
"/dlclient0/client.root",
"rz3b",
""
};

The various fields of the structure are defined in /usr/include/sas/mop.h.
Change the client's address (expressed here as a 32-bit integer), and
compile netblk.c using 'cc -c netblk.c'.

The netmask and the broadcast address can also be changed here.

==============================================
17. Is ONC RPC (formerly "Sun RPC") supported under ULTRIX - and what should I
	do to port my existing applications that rely on it? **NEW**

ONC RPC (formerly "Sun RPC") is not supported under ULTRIX. This means
that not only may some library routines like "clnt_create" not exist,
but that if they do, they may not work as expected. If you need to use
RPC for an application can use the unsupported version of the RPC4.0
distribution that is available for FTP from crl.dec.com and
decuac.dec.com in pub/sources/rpc4.0-ultrix.tar.Z.

ONC RPC will be a supported component of Digital's OSF/1 product.


==============================================
18. How can I disable forwarding of IP packets on an ULTRIX system with two
	network interfaces? **NEW**

Put this in rc.local:

echo -n 'disabling kernel routing: ipforwarding '		>/dev/console
/usr/etc/kvar -k -wl -s ipforwarding -v 0 /vmunix		>/dev/console

==============================================
19. Why doesn't ULTRIX 4.1 work with disks bigger than 1.2GBytes?

There is a bug in the V4.1 SCSI driver that will only allow it to read
something like (2 ** 21) or (2 ** 20) LBNs.  After that it wraps
around to the beginning of the disk.  It is fixed in V4.2.

==============================================
20. Where can I get a disktab entry for the XXX disk?

A collection of contributed disktab entries is in
/pub/DEC/ultrix-disktabs on the usual archive machines.  Get a copy of
the file for an up-to-date list.


==============================================
21. What does "unaligned access" mean, and how can I fix it?

Unaligned accesses typically come up when programs use malloc(3) or
other memory allocation routines in atypical ways, or when programs do
certain (hazardous) kinds of type casts.

malloc(3) returns data aligned to the most restrictive alignment (8
byte boundaries on MIPS machines).  If you are writing your own
malloc wrapper (say to add a reference count) and you write code like
this:

	char *mymalloc(int size)
	{
	  short *newmem;

	  newmem = (short *) malloc(size + sizeof(short));
	  *newmem = 1; /* initialize reference count */
	  return (char *) (newmem + 1);
        }

you are then returning a pointer that is no longer 8-byte aligned.  Now, code
like

	int *i;
	i = (int *) mymalloc(sizeof(int));
	*i = 10;

will generate unaligned access messages whenever *i is used.

An example of dangerous casting would be something like 

        char buffer[100];
        int i;

	i = (int)*((int *)&buffer[3]);

The program will usually still run correctly, because an exception
handler in the kernel performs an unaligned read.  There are some rare
cases, however, where the fixed read yields incorrect results.  The
messages are printed by default because one usually wants to know when
a program is generating the unaligned accesses.

Now, if you're only getting a few of these messages, it might not
matter, but if you're getting pages of them (or worse, have turned off
the logger because you were getting so many unaligned access
messages), you might consider correcting your program.

You can use the uac(1) (Unaligned Acces Message Control) command to
turn off the messages.

If you want to find the the problem in the source code, you can use dbx.
Suppose the message is:

	Fixed up unaligned data access for pid 2337 (bozo) at pc 0x5ad364

This tells you that the problem occurs in the program "bozo".  In dbx,
you would type, for example:

	% dbx bozo
	(dbx) 0x5ad364/i

	*[main:206, 0x0x5ad364]  lw      r0,40(sp)

dbx prints the offending instruction, along with its location: line 206
in main().
If you need to do unaligned accesses, you might find the following useful:

int unaligned_load_word(int *src);
int unaligned_load_half(short *src);
unsigned int unaligned_load_uhalf(unsigned short *src);
float unaligned_load_float(float *src);
double unaligned_load_double(double *src);

void unaligned_store_word(int *dst,int val);
void unaligned_store_half(short *dst,int val);
void unaligned_store_float(float *dst,float val);
void unaligned_store_double(double *dst,double val);

These unaligned access routines are an unsupported component of the
standard C library on RISC/ULTRIX. They provide for alignment-safe
access to the primitive data types (short,int,float,double). They are
fairly fast as they use the special MIPS unaligned instructions
(LWL,LWR,SWL,SWL) for doing the complicated part of the work.

If you are running ULTRIX 4.2, and you would like to disable the automatic
fixup of unaligned accesses, use:

#include <sys/syscall.h>
#include <sys/sysmips.h>

syscall(SYS_sysmips, MIPS_FIXADE, 0, NULL, NULL, NULL);

The above code fragment will disable address fixups for your process,
and this will be inherited by any children. Where a fixup would have
occured, you will get a SIGBUS.


==============================================
22. Where can I get a printcap entry for the XXX printer?

A collection of contributed printcap entries is in
/pub/DEC/ultrix-printcap on the usual archive machines.  Get a copy of
the file for an up-to-date list.


==============================================
23. Why does the X server use so much memory?

Xws and the other other DEC X servers generally grow larger with
workload, not because of memory leaks.  When you start an X server,
its process is quite small.  As applications are started, the server
allocates memory for a variety of reasons to service requests from
clients.  An example of this is allocating a pixmap.  When the
resource is freed, the corresponding memory is freed back to the
malloc pool, but the server image doesn't get any smaller.  This is
true of any application where you malloc memory and then free it. If
your workload is consistent, server growth is asymptotic, growing
quickly at first, then tapering off.  In other words, if you exit the
application that caused the server to allocate a lot of memory, the
server size won't shrink when the application exits, but the server
won't grow any larger if you run the same application the same way
again.

Of course it's possible that a memory leak in the server still exists.
If you think you have a memory leak, you should figure out which
application you run that triggers the leak.  You should run that
application several times, observing the server size with every
iteration.  If the server grows by an appreciable amount each time,
please file an SPR.

For workstations with minimal memory, we recommend that you use the
following server command line arguments:

	-once	(restart the server afresh for each session)
	-su 	(inhibit save unders)
	-bs 	(inhibit backing store)

The -su and -bs flags essentially trade CPU for memory, making
applications work harder in some cases to save server memory.  This
tradeoff isn't as bad as it may sound.

==============================================
24. How can I build an X11R5 server for an ULTRIX 4.1 machine?

The display device drivers changed significantly between ULTRIX 4.1
and ULTRIX 4.2.  To build an R5 server on ULTRIX 4.1 system, edit the
Edit the file ultrix.cf in mit/config and #define OSMinorVersion to be
1.  This should cause the Xcfbpmax server to be built instead of the
Xdec server.  Xdec only runs on ULTRIX 4.2.

==============================================
25. How do I change or get rid of the Digital logo on the login screen of 
	my workstation?

To have no logo displayed at all, add this line to /.Xdefaults:

	XSessionManager*displayLogo:	no

To replace the Digital logo with a different Encapsulated PostScript
image, add the following to /.Xdefaults:

	XSessionManager*logoFile:       filename
	XSessionManager*logoFullScreen: true

Make sure that "filename" is the full path to a PostScript file.
Note that the PostScript should not end with a "showpage" or the page
will print and then disappear with the "new page."

==============================================
26. How do I run MIT X11 Software?

If you are running with Ultrix 4.2 or later, you should have received
some sort of distribution media with "Unsupported" subsets on it.
Among those subsets are the following:

	UDXUNFONTS420 'Unsupported MIT Fonts'
        UDXUNMAN420   'Unsupported X11 Reference Pages'
        UDXUNMIT420   'Unsupported X11 Components'

These subsets, in total, provide the fonts, manual pages, and clients
from the X11 Release 4 distribution from MIT, with a few minimal
changes to fix problems that cropped up after the MIT release.

If all you want is R4 clients, load the above subsets.  These subsets
were built directly from the X Consortium sources and include all of
the public patches.  The R4 clients will be installed in /usr/bin/X11;
put that directory in your path in order to access them.  An ls on
/usr/bin/X11 will also reveal the names of the applications that are
available.

If you have a previous version of Ultrix, or if you need X11 Release
5, you will have to build from the X Consortium sources yourself.
There are some difficulties associated with building Release 4 from
source on Ultrix versions 4.0 and higher; fortunately, Release 5
corrects these problems, so be sure to start with a fresh Release 5
distribution.

Building from source should be a simple matter of editing the
mit/config/ultrix.cf file and then connecting to the toplevel
directory and typing ``Make World''.  If you are running Ultrix 4.2,
you don't need to edit ultrix.cf, but for other versions of Ultrix, be
sure to cd to mit/config and change the OSMinorVersion (and, for
versions of Ultrix prior to 4.0, the OSMajorVersion) number to the
appropriate number for your version of Ultrix.

As mentioned in another FAQ answer, the Xdec server provides
multiscreen capability for colour frame buffers, but features of
Ultrix required to support this capability are not present prior to
Ultrix 4.2; for those versions, the Xcfbpmax server will be built;
this server only supports one display per machine, and only DECstation
2100 and 3100 and DECstation 5000 models running with the CX adapter.

The Xdec server should work on the following systems:

        DECstation 2100 Monochrome or Color Workstations
        DECstation 3100 Monochrome or Color Workstations
        DECstation 5000/1xx CX, MX or HX Single or Multiscreen Workstations
	DECstation 5000/2xx CX, MX or HX Single or Multiscreen Workstations

The support for the HX option on the above platforms is limited to
direct frame buffer I/O - the graphics processor present on the HX
board will not be used.  This means that performance with the R5
server will be substantially worse than performance with the
DEC-supplied server in most cases.  Support for the PX and PXG options
is not present in R5 in any form.  Support for the MX exists, but some
problems have been reported when attempting to render non-black,
non-white pixels.

Source to X11 Release Five can be copied across the Internet from
gatekeeper.dec.com (16.1.0.2), crl.dec.com (192.58.206.2), or
export.lcs.mit.edu (18.24.0.12).  Other internet archives may also
have full source distributions; asking around on the Usenet newsgroup
comp.windows.x will probably elicit this information.


==============================================
27. How do I build X software that I got from the net?

If you get source code to an X application from somewhere and want to
build it, here are a few helpful hints:

First, make sure the following subsets are installed:

		UDXUNMIT420
		UDXUNFONTS420

You may also find the man pages for the previous two subsets
useful.  They're in:

		UDXUNMAN420	

Next, add the following line to the end of /usr/lib/X11/config/site.def

		#define StandardIncludes -I/usr/include/mit

If there are any README files with the source code, now is a good time
to read them, and make any changes they suggest.

If you installed the MIT X11 distribution from MIT, rather than the
ULTRIX subsets, your local configuration may be different.

If there is an Imakefile:

If the source code has a file called "Imakefile" at the top of its
directory hierarchy, typing the following in that top-level directory
should build the application:

		xmkmf
		make Makefiles
		make depend
		make

To install the application, type

		make install


If there isn't an Imakefile:

You might have to edit the Makefile to make the application compile.

If ".h" files (like those for the Athena widget set, "Xaw") are not
being found, adding "-I/usr/include/mit" to the "cc" command(s) in the
Makefile will usually do the trick.

If you are having problems linking, try using "-lXext-mit" and "-lX11-mit"
instead of "-lXext" and "-lX11" in the Makefile.

==============================================
28. Why do some applications run slowly on the DECstation PX and PXG
	displays?

The PX and PXG graphics adapters are designed for high-speed
two-dimensional vector drawing and for high-speed three-dimensional
rotation and polygon fills, respectively.  In order to get maximum
performance in these specialized areas, both kinds of adapters have
their own intelligent on-board processor which do high-speed drawing
operations, and in the case of the PXG, a general purpose RISC
processor which does 3D rendering, scaling and rotation.

In order to optimize graphics performance, a tradeoff was made on both
of these boards which prevents your system CPU from directly accessing
display memory.  Allowing your system CPU to directly access display
memory would, at a minimum, cut the graphics accelerator performance
by a factor of two, and perhaps more.

Unfortunately, as a result, operations which involve the copying of
large images (Pixmaps) into or out of display memory are performed
much more slowly than they would be if the processor were able to
directly access system memory.

One example of this is the ever-popular background image.  The X
server keeps a Pixmap containing the pattern with which to paint the
root window; whenever an area of the root window is exposed, the X
server must copy that portion of the Pixmap over the relatively
low-performance I/O channel to the PX or PXG adapter, which then
copies it into display memory.

As a result, iconifying and deiconifying windows can become a fairly
slow experience, particularly on systems with lower TurboChannel
bandwidth.  In this case, the solution is simple; just use the
standard, boring background.  However, if an application that you use
actually needs to copy Pixmaps to the screen on a regular basis, you
will definitely experience slow performance; there's no way to fix
this problem.

Unless you need the vector performance of the PX or the 3D rendering
capabilities of the PXG, use one of the several boards DEC produces
which are optimized for windowing and imaging, such as the CX (dumb
colour frame buffer), MX (dumb monochrome frame buffer), HX (smart
colour frame buffer), or TX (imaging colour frame buffer).

==============================================
29. What are the pinouts of the MMJ jacks on the back of various DECstations
	and VAXstations?

This describes the 6-pin modified modular jack (MMJ) used for serial ports
on various DECstations and VAXstations, as well as on other DEC equipment.

DEC carries four DB-to-MMJ adaptors.  They are internally wired as follows

                   Rdy Out  TX+  TX-  RX-  RX+  Rdy In            
 Adaptor   Gender     1      2    3    4    5     6       Use with:
--------------------------------------------------------------------------
 H8575-A     F      20      2    7    7    3    6&8     VTxxx terminal
 H8571-C     M       6      3    7    7    2     20     DEC printer
 H8571-D     M       6      3    7    7    2     20     Modem
 H8571-E     M      20      2    7    7    3    6&8     Female terminal
                                                        or LaserWriter
--------------------------------------------------------------------------

RS-232 using DB-25 connectors:
                                                DTE           DCE
                                             Terminal        Modem
                                            or computer
Pin Number Signal Name
    2          TD        Transmit Data                   -->
    3          RD        Receive Data                    <--
    7          GND       Ground                          ---
    6          DSR       Data Set Ready                  <--
    8          DCD       Data Carrier Detect             <--
   20          DTR       Data Terminal Ready             -->



==============================================
30. How do I set the SCSI ID on an RZ25? 

Back by the power connector are a row of 3 jumpers. These set the scsi
id. The one closest to the power connector is bit 2, and you install a
jumper to get a "1". The default id is 7, which conflicts with the
controller.  Note that the mounting bracket on the drive covers these
jumpers, so they are not immediately obvious.


==============================================
31. How can I get detailed information on the TURBOchannel? **CHANGED**


The TURBOchannel is a 32bit synchronous I/O channel that is currently
used on products in the VAX, MIPS and ALPHA architectures. It is used
in both the workstation and server based systems. Software support for
VMS, Ultrix, and OSF/1 will be provided for the applicable systems
under thos three architectures. For specific product information
contact your local DEC sales person.

Use of the TURBOchannel does not require any license or fees. It is
free to both option and system vendors alike. The documentation that
is provided on-line is available for public use and may be copied, in
its entirety, and distributed freely.


Overview information:  There is a postscript presentation available on line at

		gatekeeper:pub/DEC/TriAdd/TURBO.ps
					 /TURBO.ps.Z	(compressed file)


		The script for the presentation is a postscript file

		gatekeeper:pub/DEC/TriAdd/TURBO_README.ps
					 /TURBO_README.ps   (compressed file)


Product information:  There is a postscript version of the TRI/ADD Shippable
		      Products Catalog available for anonymous ftp at

		gatekeeper:pub/DEC/TriAdd/TAcatalog.ps
					 /TAcatalog.ps.Z   (compressed file)

		for Asian countries, the file is

		gatekeeper:pub/DEC/TriAdd/TA+catalog.ps
					 /TA+catalog.ps.Z  (compressed file)


		The catalog contains more than just TURBOchannel based
		products, but the TURBOchannel products have a special
		logo next to them which makes them easy to identify.
		An overview list (without product details) of the
		catalog is the postscript file

		gatekeeper:pub/DEC/TriAdd/shortTAcatalog.ps
					 /shortTAcatalog.ps.Z (compressed file)

			or the text file

		gatekeeper:pub/DEC/TriAdd/shortTAcatalog.txt
					 /shortTAcatalog.txt.Z (compressed)



TURBOchannel Specifications:	Are available on-line in postscript format for
				anonymous ftp at

		gatekeeper:pub/DEC/TriAdd/turbo_hw_spec.ps   (hardware spec)
					 /turbo_hw_spec.ps.Z (compressed file)

		gatekeeper:pub/DEC/TriAdd/turbo_fw_spec.ps   (firmware spec)
					 /turbo_fw_spec.ps.Z (compressed file)

		gatekeeper:pub/DEC/TriAdd/turbo_sys_params.ps (system params)
					 /turbo_sys_params.ps.Z (compressed)

		gatekeeper:pub/DEC/TriAdd/tci_spec05c.ps     (ASIC spec)
					 /tci_spec05c.ps.Z   (compressed file)

TURBOchannel Industry Group:  The TURBOchannel protocol specifications belong
			      to an open industry group. The TcIG information
			      and meeting minutes can be found in the file

		gatekeeper:pub/DEC/TriAdd/tcigmeeting.ps     (meeting minutes)
					 /tcigmeeting.ps.Z   (compressed file)

TURBOchannel Support:	Technical support for TURBOchannel Option and System
			developers is available through Digital's TRI/ADD
			Program. Membership in Digital's TRI/ADD Program is
			free of charge. For more information contact

Digital's TRI/ADD Program	1.800.678.OPEN     Canada & US
529 Bryant Ave. PAG-2		1.415.617.3452	   Outside North America
Palo Alto, CA 94301-1616	1.415.853.0155	   FAX
				triadd@decwrl.dec.com

==============================================
32. Can I mix 8-Megabyte and 32-Megabyte boards in the DECstation 5000/xxx
	family? **NEW**

All DS5000 series machines set the memory stride from the first memory
array module (this is true of the Personal DECstation and the
DS5000/1xx series and not just the DS5000/2xx machines). The only
supported configurations are those in which all of the memory array
modules are of the same capacity.

Memory array module types are:

        MS01-AA   1Mbit DRAM    DS2100,DS3100,PDS5000/20,PDS5000/25,DS5000/120,
                                DS5000/125,DS5000/133
        MS01-CA   4Mbit DRAM    PDS5000/20,PDS5000/25,DS5000/120,DS5000/125,
                                DS5000/133
        MS02-AA   1Mbit DRAM    DS5000/200,DS5000/240
        MS02-CA   4Mbit DRAM    DS5000/200,DS5000/240

However, you can place one memory array module of a smaller capacity
at the end of a series of higher capacity modules.

                Slot            Module

                 0              MS02-CA
                 1              MS02-CA
                 2              MS02-AA

This configuration will work, and be properly recognized by Ultrix,
but it is not "supported." The console will see all of the memory
modules. The operating system will be expecting memory in 32MB
segments and when it hits slot 2 it will simply believe that there are
24MB of failed memory on that module.

It will not be possible to support higher memory congigurations in the
DS5000 series machines with 16Mbit DRAM cards. The issue is that both the
physical memory address and the I/O address are provided by the same Kseg0
block (512MB) in the R3000. This will not change with the advent of the R4000
daughter cards, as it would require modification of the memory controller ASIC
(the MT chip) as well.


==============================================
33. How can I find out which type of DECstation 5000 I have? **NEW**

If /etc/sizer -c returns:
DS5000                 then it's a 5000/200.
DS5000_100             then it's a 5000/1xx (where xx={20,25,33})
DS5000_300             then it's a 5000/240.
DSPERSONAL_DECSTATION  then it's a 5000/xx.

For something more specific on the 5000/1xx and 5000/xx, you need to
look at the messages printed out at last boot time (available in the
error log; use /etc/uerf -R -r 300).

==============================================
34. What is the floating-point number representation on ULTRIX?

The floating point format differs depending on which architecture the
ULTRIX software is running on.

Digital's RISC machines all use IEEE floating point representation
with a little-endian byte ordering.  You can easily convert between
little and big endian ordering by reversing bytes within the floating
point number.

The VAX line uses a unique (although, given the popularity of VAXen)
quite well known floating point format.

The ULTRIX C libraries include routines which will translate between
RISC (IEEE) and VAX floating point formats.  Look under "ftoi" in
either the online or hardcopy documentation.

==============================================
35. If the console is a graphics device, can it be used as a terminal for
	full-screen applications?

The console emulates a dumb terminal, with no ability to address the screen.
To run anything like a screen editor, you must start the window system.

==============================================
36. How do I read a tar image from a TK50 tape if my only TK50 is on a VMS
	machine?

On VMS (assuming your tape drive on VMS is MUA0:) :
 
	mount/foreign/block=10240/record=10240 mua0:
	copy mua0: file.tar
 
On Ultrix:
 
	dcp -i 'vms::where$logical:file.tar' file.tar

==============================================
37. Where can I get free source code for interesting programs on ULTRIX?

The main FTP server for DEC is gatekeeper.dec.com, which maintains a
large selection of sources from the net in general, as well as public
code for ULTRIX, such as "monitor", "top" and other system-specific
tools.  ~ftp/pub/DEC has sources for several packages written by
employees at Digital (though they are not supported Digital products),
as well as some programs that required special changes to port to
ULTRIX.  More or less up to date copies the pub/DEC directory are also
available on crl.dec.com and decuac.dec.com. None of these sources or
utilities are "supported" by anyone other than their authors.

==============================================
38. Where can I get technical information on the DECstation family of machines?

Technical information on the DS3100, DS5000/200, and TurboChannel are
available in gatekeeper.dec.com:/pub/DEC/specs:

-r--r--r--  1 root     system     184329 Nov 19  1990 DS3100.ps.Z
-r--r--r--  1 root     system      77017 Nov 19  1990 DS5000_200.ps.Z
-r--r--r--  1 root     system       1336 Nov  6 17:36 README
-r--r--r--  1 root     system      24758 Nov 19  1990 tc_cfb.ps.Z
-r--r--r--  1 root     system      77051 Nov 19  1990 tc_ether.ps.Z
-r--r--r--  1 root     system      29304 Nov 19  1990 tc_scsi.ps.Z


Technical information on the new Personal DECstations 5000/20 and /25,
the DECstation 5000/133 and DECstation 5000/240 are available on the
net.  Included are the Technical Overviews and Info Sheets for the
products.

The files are on gatekeeper.dec.com:/pub/DEC/specs1.

-r--r--r--  1 root     system     159698 Dec 13 12:35 3maxp_info.ps.Z
-r--r--r--  1 root     system     336073 Dec 13 12:35 3maxp_teov.ps.Z
-r--r--r--  1 root     system     249185 Dec 13 12:35 3min_info.ps.Z
-r--r--r--  1 root     system     134107 Dec 13 12:35 maxine_info.ps.Z
-r--r--r--  1 root     system     311201 Dec 13 12:35 maxine_teov.ps.Z

"3maxp" ("3Max+") refers to the DS5000/240; "maxine" refers to the
Personal DECstations.

==============================================
39. Where can I get performance information about DECstations? **CHANGED**

Performance information on some of Digital's systems is
available in gatekeeper.dec.com:/pub/DEC/performance:

DECSTATION_FAMILY_PERF_SUMMARY_APR_92.PS
decstation_family_perf_summary_apr_92.ps.Z

	Results of several well-known benchmarks for the DECstation 5000
	family

DECSYSTEM_FAMILY_PERF_SUMMARY_MAY_92.PS
decsystem_family_perf_summary_may_92.ps.Z

	Results of several well-known benchmarks for the DECsystem
	family

VAXSTATION_FAMILY_PERF_SUMMARY_MAR_92.PS
vaxstation_family_perf_summary_mar_92.ps.Z

	Results of 8 well-known benchmarks for the VAXstation 4000
	family

DS5100_TPCA_INFORMIX_MAR92.PS
ds5100_tpca_informix_mar92.ps.Z

	TPC Benchmark A for INFORMIX running on a DECsystem 5100

DS5500_TPCA_INFORMIX_MAR92.PS
ds5500_tpca_informix_mar92.ps.Z

	TPC Benchmark A for INFORMIX running on a DECsystem 5500

DS5100_TPCB_INFORMIX_DEC3.PS
ds5100_tpcb_informix_dec3.ps.Z

	TPC Benchmark B for INFORMIX running on a DECsystem 5100

DS5500_TPCB_INFORMIX_DEC3.PS
ds5500_tpcb_informix_dec3.ps.Z

	TPC Benchmark B for INFORMIX running on a DECsystem 5500

DS5000_25_TPCB_INFORMIX_APR92.PS
ds5000_25_tpcb_informix_apr92.ps.Z

	TPC Benchmark B for INFORMIX running on a DECsystem 5000 model 25

==============================================
40. Why can't I submit a bug report by electronic mail?

At this time, Digital does not accept bug reports by electronic mail.  We
hope that this unfortunate situation may change in the future.  Please file
a Software Performance Report (SPR) instead.


==============================================
41. How do I send mail to Digital employees?

If you have Internet ftp capability, grab gatekeeper.dec.com:~ftp/gateway.doc,
which contains every bit of relevant lore we've ever collected on this topic.
If you must get by with what little information we have room for here in the
FAQ, well, read on.

The easiest way to find out how to get mail to a Digit is to have them
send mail to you.  If you get their mail, look at the headers (check
the "From:" line, in particular) and try sending mail to the address
as it appears to you.  (If your Digit doesn't know how to send you
mail, have them grab gateway.doc (it's DECWRL::"/gateway.doc" from the
inside) and read it carefully.

If you need to send mail to someone ``from scratch'', you will need to get
them to tell you their address.  If they say something like ``JOVE::VIXIE''
then the right way to reach them is one of:

	vixie@jove.enet.dec.com
	vixie%jove.enet@relay.dec.com
	...!uunet!decwrl!jove.enet!vixie

If on the other hand they say something like ``I'm PAUL VIXIE @WRL,'' then
you can try one of these:

	vixie@wrl.mts.dec.com
	vixie%wrl.mts@relay.dec.com
	...!uunet!decwrl!wrl.mts!vixie

In the best of all possible worlds they will say something like ``My address
is <vixie@pa.dec.com>'' in which case you should send to one of:

	vixie@pa.dec.com
	vixie%pa.dec.com@relay.dec.com
	...!uunet!decwrl!pa.dec.com!vixie

If you try most or all of the above suggestions and can not figure out what
you're doing wrong, send mail to our gateway postmaster, which is one of:

	postmaster@dec.com
	postmaster@decwrl.dec.com
	...!uunet!decwrl!postmaster

==============================================
42. How do I get a list of available patches for my release of Ultrix?

At this time, Digital does not publish lists of available patches.
The Customer Support Centers will inform you if you call about a
problem for which there is a patch.


==============================================
43. How can I get files available by anonymous FTP if I'm not connected
	to the Internet?

One way is to use the DECWRL ftpmail server.  To find out how to use
it, send a one-line message to ftpmail@pa.dec.com (or
...!uunet!decwrl!ftpmail or decwrl::ftpmail).  The subject line can be
anything you want since it will be ignored.  The text of the message
should be one unquoted lowercase word: "help".
Newsgroups: comp.unix.ultrix,comp.protocols.nfs