From: cummings@hammer.Prime.COM (Kevin Cummings)
Subject: LINUX FAQ
Date: 1 Apr 92 18:55:23 GMT
Organization: Prime Computer R&D
Mail-archive/RCS/faq.txt,v 1.5 92/03/25 15:35:30 corsini Exp $
$Log: faq.txt,v $
Revision 1.5 92/03/25 15:35:30 corsini
Corrected some bugs in devices information
Updated the devices names
Rephrazed few Q/A
Removed info about Peter init/login
Added info about creating new boot-image
Some information about rawrite, Svga
Revision 1.4 92/03/25 15:30:52 corsini
Pb with RCS hope it's fixed now
Revision 1.4 92/03/18 18:23:17 corsini
Updated minor/major for devices
Some information about the /bin/sh provided in root-image095a
Some clues for editors (keys and saving).
Information about mount and lock-files
Information about the BUGLIST
Revision 1.3 92/02/25 22:31:28 corsini
Added The "MORE HINTS" paragraph
among other things
How to use setterm for the Novice (Peter MacDonald pcmacdona@sanjuan.UVic.ca)
Information about gcc-1.40 (Hongjiu Lu firstname.lastname@example.org)
Information about init/login package (Peter Orbaek email@example.com)
Revision 1.2 92/02/03 22:28:42 corsini
Updated version, nothing special
Revision 1.1 92/01/22 22:26:22 corsini
The originall FAQ 1st version was posted in Dec. 19, by Robert Blum,
Most credits of this work to Linus, Robert and Ted, the rest was
either on the list posted by many (real) activists, not me ;-), either
in some other news groups, or else by direct posting to me (thanks
Humberto, Dan, Michael, Drew). I haven't systematically copyrighted
them, so thanks to every one who participated even indirectly to this
[To find what has changed, view the `Cdiff-faq' in my previous posting.
The last-change-date of this posting is always "two minutes ago". :-)]
This is the introduction to a list of frequently asked questions (FAQ
for short) about Linux with answers (Yeap!). This article contains a
listing of the sections, followed by the question/answer part.
This FAQ is supposed to reduce the noise level ;-) in the alt.os.linux
newsgroup (and also the 'linux-activists' mailing list), and spare the
time of many activists. I will post it twice a month, since there are
more and more new incomers, and new features.
BTW I think this FAQ should be available at the main Linux sites in
the doc directory (have you read this Ari, Robert, Ted/Michael ?). So
I will send a copy to the main sites.
Please suggest any change, rephrasing, deletions, new questions,
Please include "FAQ" in the subject of messages sent to me about FAQ.
Please use firstname.lastname@example.org whatever will be the From part
of this message.
Thanks in advance,
- verification/location/organization for files available
via FTP (I've tried what a mess!!)
- cross posting this to news.answers as soon as comp.os.linux
- reorganization of the FAQ. I don't know how, but I feel it's
needed, any help appreciated.
I. LINUX GENERAL INFORMATION
II. LINUX USEFUL ADRESSES
III. INSTALLATION and SECURITY
IV. LINUX and DOS
V. SOME CLASSICAL PROBLEMS
VI. INSTALLATION HINTS
VIII. MORE HINTS
I. LINUX GENERAL INFORMATION
QUESTION: What is linux?
ANSWER: Linux is a small unix for 386-AT computers, that has the added
advantage of being free. It is still in beta-testing, but is slowly
getting useful even for somewhat real developement. The current
version is 0.95a, date: March 17th 1992. The previous version v0.95
(March 7th) had some bugs, please do not use it anymore.
Linux 0.95(a) is a freely distributable UNIX clone. It implements a
subset of System V and POSIX functionality. LINUX has been written
from scratch, and therefore does not contain any AT&T or MINIX
code--not in the kernel, the compiler, the utilities, or the
libraries. For this reason it can be made available with the complete
source code via anonymous FTP. LINUX runs only on 386/486 AT-bus
machines; porting to non-Intel architectures is likely to be
difficult, as the kernel makes extensive use of 386 memory management
and task primitives.
QUESTION: What is the current state of Linux?
ANSWER: do "finger email@example.com", or read the
QUESTION: I've just heard about linux, what should I do to get it?
ANSWER: First read all this FAQ, and the INFO-SHEET monthly post, then
go to the nearest ftp site (see below), download the Images there are
two a rootimage and a bootimage (in general in the images directory),
download the INSTALL and RELNOTES files. Find the rawrite utility
(for example at tsx-11 it's in /pub/linux/INSTALL), then rawrite the
images on HIGH density floppies (5.25 or 3.5), finally boot on the
root diskette and that's it.
BTW From another Unix system a "dd" works fine.
After playing a while, you should want to install linux on HD (there
are scripts on the v0.95a images for that purpose), see also section
III for INSTALLATION. Then you will need
a compiler (gcc) and utilities, all can be found at the different
places described in section II below.
QUESTION: Does it run on my computer?
ANSWER: Linux has been written on a clone-386, with IDE drives and a
VGA screen. It should work on most similar setups. The harddisk should
be AT-standard, and the system must be ISA. A high density floppy
drive -- either 5".25 or 3".5
IDE and MFM seem to work with no problem. It works, also, for some
ESDI drive (Joincom controller with Magtron drive after you have
commented out the "unexpected hd interrupt"-message from hd.c). There
exists a high-level SCSI driver, under which low-level drivers are
placed; a ST-01/ST-02 low driver has been completed
Otherwise the requirements seem relatively small: a 386 (SX, DX or any
486). Any video card of the following: Hercules, CGA, EGA, (S)VGA.
It needs at least 2M to run, and 4M is definitely a plus. It can
happily use up to 16M (and more if you change some things).
QUESTION: Why the suggested 4Meg, for Linux?
ANSWER: Linux uses the first 640k for kernel text, kernel data and
buffercache. Your mother board may eat up 384K because of the chipset.
Moreover there is: init/login, a shell, update possibly other daemons.
Then, while compiling there is make and gcc (1.39 ~400k; 2.00 ~700k).
So you don't have enough real memory and have to page.
QUESTION: How would this operate in an OS/2 environment?
QUESTION: Will linux run on a PC or 286-AT? If not, why?
ANSWER: Linux uses the 386 chip protected mode functions extensively,
and is a true 32-bit operating system. Thus x86 chips, x<3, will
simply not run it.
QUESTION: Will Linux run on a 386 Laptop?
ANSWER: It works for some at least.
QUESTION: How big is the 'complete' Linux package?
ANSWER: Well, the boot and root image diskettes are about 750k
compressed. The kernel sources are about 200k compressed, and the
libc sources are another 170k compressed. The GNU C compiler is 670k,
and the other miscellaneous unix utilities are probably a bit over a
Now add sources to whatever you want to port and compile yourself.
The sources to GNU emacs are about 3 megabytes, compressed. Groff (a
troff replacement) is just over 1 megabyte.
If you think this is big, remember that the OS/2 2.0 Limited
Availability release is 20 1.44 megabyte diskettes.
QUESTION: (Dan) How long has Linux been publicly available?
ANSWER (partial): Few months, v0.10 went out in Nov. 91, v0.11 in Dec.
and the current version 0.95a is available since March 17th 92. But even
it is pretty recent it is quite reliable. There are very few and small
bugs and in its current state it is mostly useful for people who are
willing to port code and write new code.
As Linux is very close to a reliable/stable system, Linus decides that
v0.13 will be known as v0.95
QUESTION: What's about the copyright of linux.
ANSWER: This is an except of the RELEASE Notes v.095a: Linux-0.95a is
NOT public domain software, but is copyrighted by Linus Torvalds. The
copyright conditions are the same as those imposed by the GNU
copyleft: get a copy of the GNU copyleft at any major ftp-site (if it
carries linux, it probably carries a lot of GNU software anyway, and
they all contain the copyright).
QUESTION: Should I be a UNIX and/or a DOS wizard to install/use Linux?
ANSWER: Not at all, just follow the install rules, of course it will be
easier for you if you know things about Unix. Right now Linux is used
by more than 400 persons, very few of them enhance the kernel, some
adds/ports new soft, most of us are only (but USEFUL) beta testers.
Last but not least, various Linuxers work on manpages, newuser_help,
file-system organization. So join us and choose your "caste"
QUESTION: What are the differences, pros and cons compared to Minix ?
- Linux is not as mature as Minix, there is less working software right now.
- Linux only works on 386 and 486 processors.
- Linux needs 2M of memory just to run, 4M to be useful.
- Linux is a more traditional unix kernel, it doesn't use message passing.
- Linux is free, and freely distributable, BUT copyrighted.
- Linux has some advanced features such as:
- Memory paging with copy-on-write
- Demand loading of executables
- Page sharing of executables
- Multi-threaded file system
- job control and virtual memory, virtual consoles and pseudo-ttys.
- Linux is a more traditional unix kernel, it doesn't use message
QUESTION: Does Linux use TSS segments to provide multitasking?
QUESTION: If my PC runs under Linux, is it possible to ftp, rlogin,
rsh etc.. to other Unix boxes?
ANSWER: Not yet, but kermit has been ported to Linux, and the ka9q too.
QUESTION: Does linux do paging? Can I have virtual memory on my small
ANSWER: Linux0.95(a) does do paging in a better way than Linux0.12.
QUESTION: Can I have tasks spanning the full 4GB of addressable 386
memory? No more 64kB limits like in coherent or standard minix?
ANSWER: Linux does limit the task-size, but at a much more reasonable
64MB (MEGA-byte, not kilos), so bigger programs are no problem.
QUESTION: Does the bigger program sizes mean I can run X?
ANSWER: X is not (yet) ported to linux, and I hope it will be some day,
people are working hard on it but it's big, and wants a lot from
II. LINUX USEFUL ADRESSES
QUESTION: Where can I get linux?
ANSWER: Linux can be gotten by anonymous ftp from
You might want to check out which of these is the most up-to-date.
If you don't have ftp-capability, you are in trouble. See next Q/A. If
you have no uncompress utility, there are a lot even for DOS, have a
look on SIMTEL, or else use facilities provided by some sites to
uncompress for you. Don't do that if you can, because it's lengthy,
expensive and causes troubles to other users on ftp sites.
QUESTION: I do not have FTP access, what can I do to get linux?
ANSWER: Try to contact a friend on the net with those access, or try
mailserver/ftpmail server otherwise contact tytso@ATHENA.MIT.EDU. You
might try mailing "firstname.lastname@example.org" with "help" in the body of
the mail. If you choose ftpmail server (example: email@example.com),
with "help" in the body, the server will send back instructions and
command list. As an exemple to get the list of files available at tsx-11
in /pub/linux send:
reply < your e-mail>
QUESTION: Is there a newsgroup or mailing-list about linux? Where can
I get my questions answered? How about bug-reports?
ANSWER: alt.os.linux is formed, and comp.os.linux is on the way, for
those who can't access to the news you can ask for digest to:
Linux-Activists-request@NEWS-DIGESTS.MIT.EDU. On the other hand, mail
sent to Linux-Activists@NEWS-DIGESTS.MIT.EDU are posted to
DO NOT mail "I want to [un]subscribe" to the newsgroup, use
the request-address. IF not your mail-box will be over-crowded by
Questions and bug-reports can be sent either to the newsgroup or to
"firstname.lastname@example.org", depending on which you find more
appropriate. Moreover there is a BUGLIST file available in the
different main site (at least you can find it at tsx-11, in
BTW People are working on the organization of Linux, this is done on
a separate mailing-list.
linux-standards: Discussion of distribution and directory standards
for the Linux operating system, including directory structure, file
location, and release disk format.
Requests to be added to this list must be sent to:
QUESTION: Does there exist a place where the traffic of the newsgroup
ANSWER: Yes, on nic and tsx-11 (see the ftp adresses above), and since
12th March, a Gopher server is up at beryl.daimi.aau.dk
(126.96.36.199). The archives go back to Nov. 18. 91
III. INSTALLATION and SECURITY
QUESTION: I have copyed all the rootimage stuff on my HD, how can I
use the hard-disk as root?
ANSWER: There are two ways to answer this:
a) You have download the linux sources and a compiler, in that case
recompile the kernel to make a new boot-floppy according to your
environment. Just have a look in the main Makefile and in
kernel/chr_drv/keyboard.S (notice .S not .s) to set your national
b) You have nothing except the images and DOS, in that case you should
have read the INSTALLATION notices provided at your ftp site, but well:
You have to change the boot image at offset 508. The word (in
386-order, i.e low-byte first) tells the system which device to use as
root: initially it's 0 which means that we want to use a floppy of the
same type as the boot-disk (this is the reason why HIGH density
floppy is required for the boot-image).
In order to use the HD as root, this value has to be changed to point
to the correct device. For that purpose you can download the program
enclosed in INSTALL-0.10 (provided some slight modification according
to the new minor/major numbers) use the program written by Henning
Spruth wich can be found in digest#149 vol1 (there are both the C code
and the uuencoded DOS executable) or else any sector editor.
QUESTION: How can I be sure I won't be writing over anything
important? I have to use DOS on my machine, and I don't want to
lose any files.
ANSWER: Back up everything. Just in case. Then, write some easily
recognizable pattern to the partition you have reserved for linux,
using some DOS tool. You can then use "cat /dev/hdX" under linux to
examine which of the partitions you used.
QUESTION: Linux mkfs doesn't accept the size I give the device,
although I double-checked with fdisk, and it's correct.
ANSWER: Be sure you give the size in BLOCKS, ie 1024 bytes, not
sectors. The mkfs doesn't work for very big partition (over than 64
Megs). Also, make doubly certain that you have the correct partition.
There are a few rules about this: /dev/hda (under linux0.95a) corresponds
to /dev/hd0 (under minix) and /dev/hdb (linux0.95a) to /dev/hd5
(minix). DO NOT USE THEM, they are the whole raw
disk, not partitions. Also if a partition is on drive 1 under minix
(ie /dev/hd1-4), it is drive 1 under linux as well. Moreover, there
is no real consensus on whether partition #1 is the first partition on
the disk, or is the first entry in the partition table. Some parition
programs sort this information on the screen only, some will write the
sorted information back to the hard disk. Linux assumes that the
first entry is hda1, and so if some utility starts sorting/reordering
the table these things can change. Moreover, use very carefully extended
partition they are still in beta-test (this is in the installation notes).
REMARK Minix does some reordering.
A useful hack is to make each of your partitions a different size.
Then after any editting or possible change to the partition table you
can boot a floppy system and run fdisk (linux's, not DOS) to see if
the assignments still hold.
QUESTION: I have a one partitionned 40Mb disk. If I run mkfs, what
ANSWER: If you do that, you will have an empty 40Mb Linux file system.
You should, at least, make on your hard disk, one partition per
operating system you want to use.
QUESTION: I mounted the linux filesystem, and copied the files from
the root-disk to the harddisk. Now I cannot find them any more, and
somethimes linux dies with a "panic: trying to free unused inode".
ANSWER: You have probably forgot to sync before rebooting. Linux, like
all unices, use a "buffer cache" to speed up reads and writes to disk.
On a machine that has enough memory, this buffer-cache is 1.5MB, and
if you forget to sync before exiting, it may not be fully written out
to disk. Re-mkfs and re-install (or try to use the preliminary fsck,
but remember that although fsck tries to correct the faults it finds,
it may fail.)
IV. LINUX and DOS
QUESTION: Is it possible to access to DOS world from Linux
ANSWER: Yes, there is the mtools package (with patches for devices.c)
The original sources of mtools can be found at any places not only at
nic, tupac and tsx-11, and the patches for Linux (with fix for big DOS
partitions are in the directory patches or ports). Moreover you should
download the file patch.Z to apply patches :)
It is possible to find the compiled mtools stuff at mcc (see above for
QUESTION: the mtools package won't work. I get an ENOENT error message
for all devices.
ANSWER: mtools needs to be told which device to look for. Use 'ln' or
'mknod' to create a special file called "/dev/dosX", where X is A, B,
C, X or Y. A and B are for floppies (12 bits), C is for hard disk and
X, Y for any. This file should point to the device you want to read.
About the minor/major pair have a look in section INSTALLATION HINTS.
QUESTION: What is as86.tar.Z ?
ANSWER: It's the port of Bruce Evans' minix assembler, you need it to
be able to recompile Linux at your convenience. In fact this is only
used for boot/setup.s and boot/bootsect.s
BTW as86 should not work on keyboard.S, instead, you must use gcc -E
and then (g)as.
QUESTION: Turbo (Microsoft) Assembler won't compile the Linux boot
code. In fact, some of the opcodes in these files look completely
ANSWER: The Linux boot codes are written in Bruce Evans' minix
assembler, which has the same opcodes as the original minix assembler
ported to linux get as86.tar.Z Anyway there are a few differences
between these and normal DOS assemblers:
- No segments - everything is in the same segment (at least in the
bootsectors and setup, as they don't use the .data segments)
- mov[b|w|l] are shorter versions of mov ax,[byte|word|long] ptr
This is how unix assemblers normally give the size (byte, word or
Gas has similar constructs.
- There is no "jmp short", the opcodes are "j" for a short jump and
"jmp" for a long one.
- "jmpi" is a jump with a segment:offset pair. I don't know how this
written in DOS assembly.
V. SOME CLASSICAL PROBLEMS
QUESTION: While running du I get "Kernel panic: free_inode: bit
already cleared". Also, du produces a ENOENT error for all the files
in certain of my directories. What's going on?
ANSWER: These are both consistent with a bad file-system. That's
relatively easy to produce by not syncing before rebooting, as linux
usually has 1.5MB of buffer space held in memory (unless you have <=4M
RAM, in which case the buffers are only about 0.5MB). Also linux
doesn't do anything special about the bit-map blocks, and as they are
used often, those are the thing most likely to be in memory. If you
reboot, and they haven't been written to disk ...
Just do an fsck on the device, the -a flag might repair it otherwise,
the only thing to do is to reinstall the filesystem from the Images.
A sync is done only every 30 seconds normally (standard unix
practice), so do one by hand (some people think you should do 3 syncs
after each other, but that's superstition), or by logging out from the
startup-shell, which automatically syncs the system. Unmounting a
filesystem also syncs it (but of course you can never unmount root).
Another (sad) possibility is that you have bad blocks on your disk.
Not very probable, as they would have to be in the inode-tables, just
a couple of blocks in size. Again there aren't programs available to
read a disk for bad sectors and put them in some kind of
"bad-sector-file". On IDE drives this is no problem (bad sectors are
automatically mapped away).
QUESTION: How can I partition my hard-drive to use Linux?
ANSWER: There are (at least) two ways to answer this. The easy way is
probably to use a program which will do it for you, such as the MS-DOS
fdisk, Minix fdisk, Xenix/Unix fdisk, or programs such as edpart.exe
On the other hand, you can use a disk editor and modify the contents
of the partition table directly. This has been already done, and an
extensive explanatory note can be found in the mailing-list archives
(25th Jan. 92). You must also edit the bpb on the Dos partition you
are shrinking, otherwise Dos will step on Linux.
BTW It might be useful to set three (3) separated partitions for
Linux, one for the root, another one for the usr and a third one for
swap, as an illustration, my root partition is 10Meg, the usr is 22Meg
and the swap partition is 8Meg (twice the size of RAM on my box). As
an experience I have used MS-DOS fdisk to partition my two hd and got
no peculiar difficulties.
You can, as long as you stay within the 64MB per filesystem
limit, have swap, root, etc, ... all on there.
QUESTION: What must I do to mkfs a floppy?
ANSWER: blocks are of size 1K so 1.44 floppy is 1440 blocks. The
floppy has to be formatted before this will work.
QUESTION: When I run kermit under Linux, I get "Warning, Read access
to lock directory denied". What am I doing wrong?
ANSWER: Nothing, you just need to create /usr/spool/uucp, which is
where kermit like to lock files.
QUESTION: du seems buggy when i used it the number of disk occupation
ANSWER: Take care, if you want size in kbytes use the -k flags.
QUESTION: du works just fine on directories, except on / and /dev,
moreover "ls -l" returns either big or negative number on /dev. Why?
ANSWER: This is a "feature" added in Linux 0.12; it was originally
present in Minix; more specifically, when you stat a device file
belong to a block device, it will return the maximum size of the block
device in the st_size member of the stat structure. If you don't like
it, it's very simple to patch it out. Look in the fs/inode.c, in the
QUESTION: When I try to (un)compress many files in one command, the
command partially fails?
ANSWER: This is a bug, many partial fixes are floating around but ..
You can solve it by a bash command "for i in whateverfiles;do
compress $i; done". Another possibility is to download the
QUESTION: I can do this as root but not as non-root, is it a bug?
ANSWER: Except for the make utility, the problem is caused by an
incorrect permission flag. The most common problems are about /tmp
which should be 777 and /dev/ttys? which might be 766. So as root do
chmod 777 /tmp ; chmod 766 /dev/ttys?
QUESTION Sometimes, I get "mount can't open lock file"; what does this
ANSWER: This can happened for two reasons:
A) You try to mount something as non-root. In that case you can either
retry as root, or set the setuid bit to mount.
B) You are root. mount wants to open /etc/mtab and /etc/mtab~ - the
first one for reading, the second as lock file. If there is already a
mtab~ remove it. This can happen if you used once gnuemacs on mtab.
VI. INSTALLATION HINTS
QUESTION: Where can I find the basic starting help?
ANSWER: You have to download the INSTALL notes, and more specially
the 0.11, 0.12 and the current one 0.95(a). Pretty soon, a special
help for beginners will be available on the net.
QUESTION: I've got all the things on site ??? but I don't know what
ANSWER: include.tar.Z goes to /usr/include; system.tar.Z contains
the latest sources of the
system files (mkswap, mkfs, fsck and fdisk). In version 0.12
utilbin.tar.Z has been replaced by fileutil.tar.Z and utils.tar.Z
which contains a new tar to handle the symbolic links, make, uemacs
kermit and minor programs (sed,...). Other utilities have been ported
QUESTION: I don't know how to install gcc stuff, is there special places?
ANSWER: It depends on the release of gcc you are using. Right now
there are 3 packages : the original one gccbin.tar.Z contains all
the gcc-1.37 binary distrib; recently the gcc-1.40 has been ported,
it's in newgcc.tar.Z and a few days ago the BETA version of gcc-2.0
A) gccbin.tar.Z goes in /usr/local/lib except gcc which goes in
/usr/local/bin. Moreover each gcc-xxx of /usr/local/lib should be
linked with gxxx and xxx in /usr/local/bin.
B) newgcc.tar.Z goes in /usr, then uncompress and untar it. Files are
directed to /usr/lib, /usr/include and /usr/bin. You have to link ar,
as, ld with gar, gas and gld, this will prevent some error while using
make (especially whilst re-compiling Linux kernel). More information can
be found in section VIII.
C) gcc-2.0 is splitted in 2 files 2lib.tar.Z and 2misc.tar.Z, to
install them do the following:
tar xvofvz 2misc.tar.Z
read the FAQ in /usr/gcc2/install. Then
tar xvovfz 2lib.tar.Z
QUESTION: When I use the images, and i type "tar xvf ..." I got
"command not found". What did I wrong?
ANSWER: Nothing, in the distribution of 0.95 there is no tar (due to
lack of place); you should get the 0.12 images where the tar is in
compressed form (lack of place). You have first to copy tar.Z on
another disk/diskette and uncompress it, this command is available
on your diskettes.
BTW tar and compress are back in v0.95a distrib.
QUESTION: It seems that $#@! ported on linux don't run correctly
ANSWER: Possible, but check first if the size of your file corresponds
to the one on the ftp sites, if it is then check the BUGLIST available
on the main linux sites. If the bug is not reported, do a complete
report of the error, try to correct it and send your result to
QUESTION: Does anyone port this to linux?, if not i'll compile it
ANSWER: First check on the sites, have a look to the info-sheet
monthly post and also available on sites. Have a look in the "old"
digest files and mail-archives of linux-activists, these are kept at
least at tsx-11 and nic possibly at tupac. Look also at the GNU(*)
utilities to see if someone has already written a freely distribuable
version. Ask then on the list/news.
(*) GNU stands for GNU's Not Unix, which (besides being a recursive
acronym) is a project started by the Free Software Foundation (the FSF)
to write a freely distributable version of Unix. The GNU kernel is
named HURD, and is based on Mach. It is currently being written, and is
not yet done. Many of the GNU utilities, however, are completed and are
much more functional than the original Unix utilities. Since they are
freely available, Linux is using them as well.
QUESTION: I've ported *** to Linux, what should i do to add it in the
ANSWER: Read first the previous Q/A, then to make something available to
others you have to post it (with cdiffs of the source, a short README)
in the incoming directory of one of nic,tupac,tsx-11, then drop
a short note to the list/group and to the site advisor.
On nic it's email@example.com (Ari Lemmke)
On tupac it's firstname.lastname@example.org (Robert Blum)
On tsx-11 it's email@example.com (Ted Ts'o and Michael Johnson)
QUESTION: I want to port *** to Linux, what are the flags?
ANSWER: Recall that Linux implements subset of SYSV and POSIX, so
-DUSG and -DPOSIX work in general. Moreover throw away most of the ld
flags such as -ltermcap, -lg, since the libg.a and libtermcap.a are
QUESTION: Linux lacks on ****/ Linux has a bug in ***, what are the
rules to enhance/correct the kernel?
ANSWER: Before anything check if some one else is working on that
subject, contact those people, since end february a buglist (thanks to
Michael Johnson) is kept on the major sites. Test your improvment (it
should work is NOT enough), then send the patches in cdiffs form to
Linus and/or the list, moreover the localization must be clear. This
does NOT mean that bug-reports and patches are not accepted. Moreover,
you should sent a brief note to Michael: firstname.lastname@example.org
QUESTION: I seem to be unable to compile anything with gcc. Why?
ANSWER: If you have only 2 MB RAM, gcc will die silently without
compiling anything. You must have at least 4 MB to do compilations
BTW Since swapping is possible, I have heard that compilation works
with only 2Meg and a lot disk traffic :) Isn't it great?
QUESTION: I'm using a program that uses signal handlers which are
installed using sigaction() with the SA_NOMASK, and they get a general
protection error right after the signal handler tries to return.
What's going wrong?
ANSWER: You are using a libc.a that has an out-of-date signal.o and
sig_restore.o file, and they don't know how to deal with SA_NOMASK.
(The one in gccbin.tar.Z is out-of-date). Get the new libc.a and put
it in /usr/lib or /usr/local/lib. Again check your compiler version
QUESTION: gcc complains about not finding crt0.o and the system
include files What am I doing wrong ?
ANSWER: The include files normal place is in /usr/include. lib*.a and
*.o should be in /usr/lib or /usr/local/lib
QUESTION: While compiling some GNU packages gcc chokes on regex.c with
an insn code, what can I do?
ANSWER: There is a little bug in the port of gcc-1.37, this will be
corrected on the port of v2.0 (with g++). Right now throw away the -O
flag (to compile regex) and every thing will be alright.
BTW there are some minor bugs with this release of gcc because it was
compiled under linux-0.10, whith odd libraries. These problems should
have disappeared with the new gcc-1.40 package.
QUESTION: I tried to port a /new/ version of gnu stuff. But in the
linking phase, gcc complains about the missing libg.a. In fact it
depends on the gcc package you use.
ANSWER: Yes this is well known, throw away the flag -g that's all,
anyway libg.a is /only/ for debugging purpose.
QUESTION: What are the device minor/major numbers?
ANSWER: (early Linus mail Nov. 6th 91, last update Jan. 19th 92)
Memory devices: Major = 1 (characted devices) minor
2 /dev/kmem - not implemented (easy, but I haven't done it)
4 /dev/port (implemented, but untested - don't play with it)
example: "mknod /dev/null c 1 3"
Floppy disks: Major = 2 (block devices)
minor = drive + 4*type, drive = 0,1,2,3 for A,B,C or D-diskette
type 1: 360kB floppy in 360kB drive (5.25")
2: 1.2M floppy in 1.2M drive (5.25")
3: 360kB floppy in 720kB/1.44Mb drive (3.5")
4: 720kB floppy in 720kB/1.44Mb drive (3.5")
5: 360kB floppy in 1.2M drive (5.25")
6: 720kB floppy in 1.2M drive (5.25")
7: 1.44M floppy in 1.44M drive (3.5")
Thus minor nr for a 1.44Mb floppy in B is: 1 + 4*7 = 29, and to read
an old 360kB floppy in a 1.2M A-drive you need to use minor= 0 + 4*5
Example: "mknod /dev/PS0 b 2 28" (b for block: 2 for floppy, 28 for
1.44 in A)
Hard disks: Major = 3 (block devices) minor
0 /dev/hda - The whole hd0, including partition table sectors
1 /dev/hda1 - first partition on hd0
4 /dev/hda4 - fourth partition on hd0
5 /dev/hda5 - Extended partition
64 /dev/hdb - The whole hd1, again including partition table info
65 /dev/hdb1 - first partition on hd1
68 /dev/hdb4 - fourth partition on hd1
69 /dev/hdb5 - extended partition on hd1
NOTE! Be /very/ careful with /dev/hda and /dev/hdb - you seldom need
them, and if you write to them you can destroy the partition tables:
something you probably don't want. The only things that use /dev/hda
are things like "fdisk" etc.
NOTE 2!! The names for hd's are no longer the same as under minix,
there is a straightforward correspondance, but I think
minix orders the partitions in some way (so that the partition numbers
will be in the same order as the partitions are physically on the
disk). Linux doesn't order anything: it has the partitions in the
same order as in the partition table (ie /dev/hd?1 might be physically
NOTE 3!! Extended partitions are recently detected, use them VERY VERY
Tty's: Major = 4 (character devices) minor
0 /dev/tty0 - general console 1 -
63 - reserved for virtual console
64-127 - reserved for serial io
128- - reserved for pty's
And more particularly we have:
64 /dev/ttys1 - com1
65 /dev/ttys2 - com2
66 /dev/ttys3 - com3
67 /dev/ttys4 - com4
QUESTION: How to start Linux from drive B?
ANSWER: There is a DOS utility called boot_b.exe (look at DOS ftp).
Another simple way is to open the box and invert the cables.
QUESTION: The program boot_b works fine /but/ once the first disk is
read the system go back to the first drive, any hints?
ANSWER: Yes, change the bootimage in just the same way that you change
it to boot on the hard drive, execept that the major/minor pair is
different. All these information are in the file INSTALL-0.10.
Remember that if you use a sun or other endian machine, you will need
to reverse the byte order when you run the filter program (also in the
QUESTION: I've read that linux has virtual consoles, what must I do to
ANSWER: Yes there are, you can access them with the left -key
together with -key. With the Linux 0.95a Images distribution, 4
consoles are available, agetty runs on them.
BTW: the serial ports are now /dev/ttys1 and /dev/ttys2. tty0 is the
general console. tty128- are reserved to pty's
QUESTION: What kind of shell is /bin/sh ?
ANSWER: Until v0.95 it's the Bourne Again Shell, bash-1.11 and
compilation was straightforward (Linus dixit), just "make"
that's all or nearly. But as the shell comes bigger and bigger the
v0.95a /bin/sh is ash the BSD 4.3 sh.
BTW I think that next time, it will be rc which is much more better
than ash and tiny wrt bash. If you want to test it, it's (at least) at
nic in /pub/unix/shells and the file is rc-1.2.tar.Z . The compilation
is straightforward (just a few things to modify in Makefile and
QUESTION: Does there exist a man page for **** ?
ANSWER: Download man.tar.Z from your favorite linux ftp site, there is
most of the fileutils man page -- either **** or g****, example there
is nothing on ld, but there is for gld :) --, check the whatis
database provided. The files in the cat1 dir are pre-formatted man
pages that the man program can use.
BTW there is no roff,troff nor nroff for Linux. Cawf 2.0 works just
fine for simple man pages, and a partial ms support too. Quite
recently the port of groff has been done (due to gcc2.0 port), you can
found it (at least on tsx-11) in pub/linux/binaries/usr.bin/groff.
Moreover Michael Johnson is the coordinator for man pages under Linux,
he is looking for volunteers, so contact him (email@example.com).
QUESTION: What are the editors available in linux?
ANSWER: Right now there are uemacs, elvis-1.4, some one (R. Blum)
is working on some other vi clone. The port of emacs 18.57 has been
done by John T Kohl, files can be found at the different sites
at nic it's in the directory xtra
at tsx-11 it's in the directory ports/emacs-18.57.
Also the port of mg (micro gnu) has been done and can be found at
least at athos.rutgers.edu (188.8.131.52) in pub/linux, mg is the binary
and mg.tar.Z is the sources file. You can also find a PD ed, and elvis
has an ex mode.
QUESTION: Does there exist a printer package for Linux?
ANSWER: There are lp patches for linux.0.12, which implement a
parallel printer interface and feature a greatly improved driver
design. the patches are in lp.12.tar.Z As I have no printer (yet), I
don't know how good it is. There is nothing yet for 0.95(a), but I've
been told that the patch for v0.12 will fit the v0.95 and possibly the
QUESTION: Does there exist a ps for Linux?
ANSWER: Yes, a very simple one is implemented by default, just press
the scroll-lock key; ctrl-shift-scrollock gives a kind of memory
status. There is also a much more complete ps/memory package it's
ps095.tar.Z. I have tested it, it's GREAT and well documented.
QUESTION: It's nice to have the df utility, but it would be nicer if
it would give statistics of the root file system. Would it be
difficult to do?
ANSWER: surely not, in your file /etc/rc, instead of the line
put the following
echo "/dev/hdX (root)" > /etc/mtab
where the X is the hard drive you use as root partition.
QUESTION: How do I make swapping work?, when I boot I get the
following message: "Unable to get size of swap device"
ANSWER: Quite simply, you need the swapon and the mkswap binaries.
Then you can choose between a swap partition or a swap file
QUESTION: When I boot I get one of the following messages:
"Unable to find swap signature" or "Bad swap-space bitmap"
ANSWER: You probably forgot to make your swap-device, use the mkswap
QUESTION: How do I know if it is swapping?
ANSWER: You will notice it :)) First of all, Linux tells you at boot
time, "Adding swap: XXX pages of swap space", and if you start running
out of memory, you will notice that the disk will work overtime, and
things slow down. Generally a 2Meg RAM will make the system swap
constantly while running gcc, 4 Meg will swap occasionnaly when
optimizing big files (and having other things active, such as make).
QUESTION: How is it possible to remove a swap file?
ANSWER: Simply perform a rm on that file, and remove the swapon of
your /etc/rc file.
QUESTION: How is it possible to remove a swap device?
ANSWER: mkfs the device, and remove the swapon of your /etc/rc file.
QUESTION: Is there only the %$#@ keyboard ?
ANSWER: There are Dannish, Finnish, French, German, Uk and US
keyboards. Set it in linux/kernel/chr_drv/keyboard.S, then
compile the kernel again.
QUESTION: (special FINNISH/US) I booteed up with the new image and
everything work except that some keyboard keys produce wrong
characters. Does anyone know what is happening?
ANSWER: images of 0.95a are US product (and so are US-keyboard
oriented), BUT linux sources are FINNISH product, and so the default
keyboard is set to be FINNISH. The solution is in the previous Q/A.
QUESTION: Does there exist shared libs ?
ANSWER: They seem to work. The kernel features are in Linux 0.12
QUESTION: Does Linux permit/support bitmapped graphics on vga/svga
ANSWER: No, there is no interface for graphics operations on Linux
(yet). Some work has been done by Orest Zborowski (mmap/munmap, and
vga demonstration). The (un)mmap was patches for 0.12 kernel, but I've
been told that new versions (for 0.95a) will be out in a short while.
QUESTION: There are a lot of patches available (fd patch, lp patch
login patch ...) can I be fairly confident the subsequent patches will
ANSWER: This is not true yet for the current version; but it will be
so I kept it :)
No you can't, patching is a real beta tester art :)). People are not
working on the same patched release, so you have to check if the
patches you already applied works on the same kernel part, if not,
/great/, just apply them. If yes, check if there is an order, patch
creator knows that, and (should) try to warn patch user (in other
words: beta tester) otherwise you should edit the patch files (and
possibly make a brief note to others on this list/newsgroup or even a
cdiff) before applying them, another solution is to keep cool and wait
for the next version of Linux where, in general, the modifications
have been done but this behavior is /not/ Linux helpful.
QUESTION: I got the patches on some ftp sites, and applied them to the
kernel and tried to compile. It didn't !!. Are the patches buggy?
ANSWER: Before remake, just do a make clean in the directories
involved by the patches. This will force a rebuild of the .o and .a
If you have a RCS running on your source tree, did you checked a
patched version of the files changed before /any/ CO either by you or
Finally, make sure the patches succeded. Normally, failed patches on a
file FILE will leave a FILE# file. Moreover you will get a "chunk
failed" message. It is possible to capture the output while patching:
patch -p0 < patchfile | 2>&1 patch.result | more
VIII. MORE HINTS
This part is recent and try to keep track of the different information
that appeared in alt.os.linux and on the list since beginning of
February. I tried to update it for v0.95(a), so there might be some
mistakes. Moreover take care to use the correct library and include
stuff, and the ad-hoc gcc you use !!!
QUESTION: How can I backup my Hd under Linux ?
ANSWER: I know at least two ways. One possibility is tar and mtools,
another possibility is the diskbackup/diskrestore of Diamano Bolla
(digest44 vol. #1) which saves big hd to floppies using the
stdin/stdout. These utilities have been uploaded to the major sites in
An example usage (Roger Binns) is:
tar cvf - bin dev usr etc .. | compress | diskbackup
and to restore:
diskrestore | uncompress | tar xvf -
QUESTION: How to use setterm: for the novice?
ANSWER:The setterm utility provides access to most of Virtual Consoles
(VCs) functionality. You can set your screen up to blank at 10
setterm -blank 10
You can set colors, and clear the screen. For a full list of commands,
just type "setterm" with no arguments.
There are a few tricks with the screen dumper can really make VCs go a
long way. Here are a few of the common ones that I use:
Dumps the contents of the current VC to screen.dump (in the current dir).
setterm dump 4
Dumps the contents of VC 4 to screen.dump
setterm -file mydumpfile -dump 4
Dump the contents of VC 4 to the file mydumpfile
setterm -file /dev/tty0 -dump 4
Dumps the contents of VC 4 to the current VC.
setterm -file /dev/tty4 -dump
Dumps the contents of the current VC to VC 4.
setterm -file /dev/ttys1 -dump
Dumps the contents of the current VC to the serial port.
Handy if you are logged on and want to paste a screen full without
having to resort to doing a file transfer.
setterm -file mydumpfile -append 4
Appends to instead of overwriting the dump file. Useful if you
have several screens you wish to concatenate.
QUESTION: I've tried clear/reset, like most of unix but it doesn't
work, have I missed something?
ANSWER: setterm -clear or setterm -reset will solve your missing. For
clear, you can also write a small script (which use the cl: part of
/etc/termcap wrt your TERM), or use bash where ctrl-l will do it for
QUESTION: I know there are VC, but where is the setterm stuff?
ANSWER: It's in the current distribution (i.e. on the images), the
source can be found in virtcons.tar.Z at nic.
QUESTION: While using emacs in 80x25 mode, the mode line is constantly
moving around, why?
ANSWER: This appear to be a bug in the scroll region handling of the
console. I have not tested the new termcap but with the one for 0.12 I
use the following function.
QUESTION: When I use make as non root, it doesn't work, why?
ANSWER: ?????, the message is either (null) setuid ..., or (null)
setgid... I don't know how to fix it.
BTW This problem does not exist with the pmake (make for BSD 4.3 Reno
and BSD 4.4) package.
QUESTION: How can I get Linux to boot directly from the harddisk?
ANSWER: Right now, this can be done via the shoelace stuff or the
bootany package. Quite recently a monitor program has been posted for
Minix, Michael is working on the port to Linux.
QUESTION: Sometimes, when I want to remove a directory, I get an error
message, is it a (known) bug?
ANSWER: No, There is no bug at all, you probaly have another shell
on another VC whose working directory is either the one you try to
remove, either a subdirectory of it.
QUESTION: can anyone give me a sample /etc/inittab entry for login
from a pc attached to serial line /dev/ttys2?
ANSWER: "Humberto speaking :)"
First step up the modem to turn off echo and enable auto answer, I do
this in kermit by connecting to the modem and typing "ate0s0=1"
followed by enter (w/o quotes). Then setup inittab to spawn getty on
ttys2:console:/etc/agetty -m 1200 ttys2
Then it should work. Some modems can be permanently set to disable
echo and set auto answer, see your manual.
QUESTION: When compiling some code, cc1 complains about some insn
code, what's that?
ANSWER: An insn is an internal representation that gcc uses when
compiling. The main part of gcc is to take ordinary c (or c++) code,
and compile it, while ding optimizations in insn part, which is
soft/hard independant. Then another part which is hard/Os dependant
takes the insns and translate it in assembly language. The fix is only
to turn off the optimization flag (-O) or download the new gcc release
(1.4) which has been made available at tsx-11 (newgcc.tar.Z and the
ad-hoc libraries newlibc.tar.Z).
QUESTION: While compiling some stuff, I'm getting the following
Undefined symbol ___addsf3 referenced from text segment
as well as ___mulsf3 and __cmpsf2.
These symbols are not in the program or in it's header files.
ANSWER: These are math helper functions, and you can usually compile
these programs to use the kernel floating point routines by adding
'-m80387' to the compiler switches. If the program does any wierd
fp math (exp(), sin()) it'll die when you run it though.
QUESTION: What are the enhancement of the newgcc.tar.Z ?
ANSWER: There were some bugs in the old port that have been corrected,
moreover this package contains 387 support
there is libm.a (for those with 387)
libsoft.a (for those without, I for example)
libtermcap.a (from tput 1.10)
The -mstring-insns option is no longer needed nor supported :( [As
an example to recompile (successfully) linux0.12 you have to throw away
this flag in all the Makefile]
gcc-1.40 has some registers problem, you should had -fcombine-regs
flag while compiling (the linux kernel for example)
BTW Notice also that include files have changed (stdio.h which is no
more ansi compliant).
QUESTION What's about gcc2.0 ?
ANSWER: It has been ported to linux, but remember that gcc2.0 is an
ALPHA, it is not (yet) stable but it works. Anyway the files are
2lib.tar.Z and 2misc.tar.Z Uncompress and untar 2misc, read the FAQ
enclosed and play with it. You can find these files at tsx-11 in
binaries/compilers/gcc-2.0. In a short while gcc-2.1 will be out, and
will fix many problems.
QUESTION: What can gcc-2.0 do for me, that gcc-1.40 cannot?
ANSWER: Shared libraries: small programs shrink by an average factor
of 2~3, larger program by 50K. It also compiles C++, and so replace
both gcc-1.xx and g++1.xx
QUESTION: I've been trying to get Linux to run on my [3/4]86 box. It
can't even boot. Any suggestions?
ANSWER: The most common error/problem is writing the bootimage to a
low density disk. It fits, but the bootstrap code will only recognize
high density disk. So try to format explicitely disk as high density:
- for 3.5", 'format a: /n:18 /t:80 '
- for 5.25", 'format a: /n:15 /t:80 '
QUESTION: Does there exist games, languages (other than C), and
anything which make the system more friendly?
ANSWER: Yes, among other things there are rogue and yatzee; TeX;
Prolog.. but in general, if you want some extra tool port it to Linux
this is also a good beta-testing exercice.
QUESTION: Could someone explain how to use rawrite?
ANSWER: Well, rawrite is a DOS util, which write sequential sector of
a formatted disk/floppy. When a floppy has been rawritten, you can
(under Linux), mount and untar it (only use x, v and f flags). Do not
rawrite compressed files.
QUESTION: Does emacs handle the arrows-key
ANSWER: Yes it does, one simple way is to put some elisp code in your
..emacs, this is an except of mine:
(fset 'esc-c-prefix esc-c-map)
(define-key global-map "\e[" 'esc-c-prefix)
(define-key global-map "\e[B" 'next-line)
(define-key global-map "\e[A" 'previous-line)
(define-key global-map "\e[C" 'forward-char)
(define-key global-map "\e[D" 'backward-char)
The keycode was obtained by ^Q followed by the key
QUESTION: Whenever I use uemacs 3.1X on a symlink, the symlink does
not exist anymore, why?
ANSWER: (Tristram Mabbs) Since ue3.10, uemacs uses 'safe save' mode,
writing the file to a temporary and moving it OVER the original. In
the process, this deletes the original. To prevent this just add the
following in your emacs '.rc' file: set $ssave FALSE
QUESTION: Uemacs doesn't work anymore with 0.95a, whenever I want to
save a file; what can I do?
ANSWER: ^S and ^Q are used for flow control. One solution is ^X^W
followed by the filename, or M-X save-file. Another possibility,
if you have download the stty.tar.Z file, is to do stty -IXON
before you first use uemacs (this can be included in your .profile).
And the last is to recompile the Peter Orbaek init-1.2 package.
QUESTION: I have an SVGA, but Linux detect an EGAc/EGAm; is it normal?
ANSWER: (Jim Winstead) This is correct actually. You have an EGA+ card
(SVGA) with a Color/Mono monitor. The only four possibilties are EGAc,
EGAm, *MDA and *CGA (according to the code in
The true test, if Linux detects your video card, is if you press
< RETURN> at the "Press < RETURN> to see SVGA- ..." boot-time message.
If you have a SVGA recognized card, it will ask you to choose a
screen size. If not detected, the default is 80x50 mode.
BTW if you have no SVGA, press the < space> and you are in 80x25 mode.
Kevin J. Cummings Prime Computer Inc.
20 Briarwood Road 500 Old Connecticut Path
Framingham, Mass. Framingham, Mass.
Std. Disclaimer: "Mr. McKittrick, after careful consideration,
I've come to the conclusion that your new
defense system SUCKS..." -- War Games