                     TWIN FREQUENTLY ASKED QUESTIONS
		            WITH ANSWERS
			    
                            28 Oct 2002
                Massimiliano Ghilardi <max@linuz.sns.it>

This is the list of Frequently Asked Questions about twin,
a Textmode WINdow environment
[see Q1.1 `What is twin ?' for more details].
It should be read in conjunction with the other documents
describing twin, in particular the Tutorial.
This file, and also a lot of other documents about twin,
is distributed together with twin sources at:

* http://sourceforge.net/project/twin/
* http://linuz.sns.it/~max/twin/

and mirror sites thereof. See Q2.1 `Where can I get the documentation about
twin ?' for a list of the available documents and more information.

Please check out these documents and this FAQ, especially Q12.1 `You still
haven't answered my question !', before sending your question.

A new version of this document is released at each new version of twin,
which means approximately monthly.  If this copy is more than a month old
it may be out of date.

===============================================================================

Index

 Section 1.  Introduction and General Information
 Q1.1        What is twin ?
 Q1.2        Does it run on my computer ?
 Q1.3        Can twin display on X ? On Linux console ? On ... ?
 Q1.4        What software does it provide ? Which programs require twin ?
 Q1.5        What ports to other operating systems are there ?
 Q1.6        Is twin PD ?  Copyrighted ?

 Section 2.  Network sources and resources
 Q2.1        Where can I get the HOWTOs and other documentation ?
 Q2.2        Where should I look on the World Wide Web for Linux stuff ?
 Q2.3        What newsgroups are there for Linux ?
 Q2.4        How do I install Linux ?
 Q2.5        Where can I get Linux material by FTP ?
 Q2.6        I don't have FTP access.  Where do I get Linux ?
 Q2.7        I don't have Usenet access.  Where do I get information ?
 Q2.8        What mailing lists are there ?
 Q2.9        Are the newsgroups archived anywhere ?

 Section 3.  Compatibility with other operating systems
 Q3.1        Can Linux share my disk with DOS ?  OS/2 ?  386BSD ?  Win95 ?
 Q3.2        How do I access files on my DOS partition or floppy ?
 Q3.3        Can I use my Stacked/DBLSPC/etc. DOS drive ?
 Q3.4        Can I access OS/2 HPFS partitions from Linux ?
 Q3.5        Can I access BSD FFS, SysV UFS, Mac, Amiga, etc filesystems ?
 Q3.6        Can I run Microsoft Windows programs under Linux ?
 Q3.7        How can I boot Linux from OS/2's Boot Manager ?
 Q3.8        How can I share a swap partition between Linux and MS Windows ?

 Section 4.  Linux's handling of filesystems, disks and drives
 Q4.1        How can I get Linux to work with my large disk ?
 Q4.2        How can I undelete files ?
 Q4.3        Is there a defragmenter for ext2fs etc. ?
 Q4.4        How do I format and create a filesystem on a floppy ?
 Q4.5        I get nasty messages about inodes, blocks, and the suchlike
 Q4.6        My swap area isn't working.
 Q4.7        How do I remove LILO so my system boots DOS again ?
 Q4.8        Why can't I use fdformat except as root ?
 Q4.9        Is there something like Stacker or Doublespace for Linux ?
 Q4.10       My ext2fs partitions are checked each time I reboot.
 Q4.11       My root filesystem is read-only !
 Q4.12       I have a huge /proc/kcore !  Can I delete it ?
 Q4.13       My AHA1542C doesn't work with Linux.

 Section 5.  Porting, compiling and obtaining programs
 Q5.1        How do I port XXX to Linux ?
 Q5.2        What is ld.so and where do I get it ?
 Q5.3        Has anyone ported / compiled / written XXX for Linux ?
 Q5.4        Can I use code or a compiler compiled for a 486 on my 386 ?
 Q5.5        What does gcc -O6 do ?
 Q5.6        Where are <linux/*.h> and <asm/*.h> ?
 Q5.7        I get errors when I try to compile the kernel.
 Q5.8        How do I make a shared library ?
 Q5.9        My executables are (very) large.
 Q5.10       Does Linux support threads or lightweight processes ?
 Q5.11       Where can I get `lint' for Linux ?
 Q5.12       Where can I find `kermit' for Linux ?

 Section 6.  Solutions to common miscellaneous problems
 Q6.1        free dumps core.
 Q6.2        My clock is very wrong.
 Q6.3        Setuid scripts don't seem to work.
 Q6.4        Free memory as reported by free keeps shrinking.
 Q6.5        When I add more memory it slows to a crawl.
 Q6.6        Some programs (e.g. xdm) won't let me log in.
 Q6.7        Some programs let me log in with no password.
 Q6.8        My machine runs very slowly when I run GCC / X / ...
 Q6.9        I can only log in as root.
 Q6.10       My screen is all full of weird characters instead of letters.
 Q6.11       I have screwed up my system and can't log in to fix it.
 Q6.12       I've discovered a huge security hole in rm !
 Q6.13       lpr and/or lpd aren't working.
 Q6.14       Timestamps on files on msdos partitions are set incorrectly.
 Q6.15       How do I get LILO to boot the vmlinux file ?

 Section 7.  How do I do this or find out that ... ?
 Q7.1        How can I get scrollback in text mode ?
 Q7.2        How do I switch virtual consoles ?  How do I enable them ?
 Q7.3        How do I set the timezone ?
 Q7.4        What version of Linux and what machine name am I using ?
 Q7.5        How can I enable or disable core dumps ?
 Q7.6        How do I upgrade/recompile my kernel ?
 Q7.7        Can I have more than 3 serial ports by sharing interrupts ?
 Q7.8        How do I make a bootable floppy ?
 Q7.9        How do I remap my keyboard to UK, French, etc. ?
 Q7.10       How do I get NUM LOCK to default to on ?
 Q7.11       How can I have more than 128Mb of swap ?

 Section 8.  Miscellaneous information and questions answered
 Q8.1        How do I program XYZ under Linux ?
 Q8.2        What's all this about ELF ?
 Q8.3        What is a .gz file ? And a .tgz ? And ... ?
 Q8.4        What does VFS stand for ?
 Q8.5        What is a BogoMip ?
 Q8.6        What is the Linux Journal and where can I get it ?
 Q8.7        How many people use Linux ?
 Q8.8        How should I pronounce Linux ?

 Section 9.  Frequently encountered error messages
 Q9.1        Unknown terminal type linux and similar
 Q9.2        During linking I get Undefined symbol _mcount
 Q9.3        lp1 on fire
 Q9.4        INET: Warning: old style ioctl(IP_SET_DEV) called!
 Q9.5        ld: unrecognized option '-m486'
 Q9.6        GCC says Internal compiler error
 Q9.7        make says Error 139
 Q9.8        shell-init: permission denied when I log in.
 Q9.9        No utmp entry.  You must exec ... when I log in.
 Q9.10       Warning - bdflush not running
 Q9.11       Warning: obsolete routing request made.
 Q9.12       EXT2-fs: warning: mounting unchecked filesystem
 Q9.13       EXT2-fs warning: maximal count reached
 Q9.14       EXT2-fs warning: checktime reached
 Q9.15       df says Cannot read table of mounted filesystems
 Q9.16       fdisk says Partition X has different physical/logical ...
 Q9.17       fdisk: Partition 1 does not start on cylinder boundary
 Q9.18       fdisk says partition n has an odd number of sectors
 Q9.19       mtools says cannot initialise drive XYZ
 Q9.20       At the start of booting: Memory tight
 Q9.21       You don't exist. Go away.

 Section 10. The X Window System
 Q10.1       Does Linux support X Windows ?
 Q10.2       Where can I get an XF86Config for my system ?
 Q10.3       xterm logins show up strangely in who, finger
 Q10.4       I can't get X Windows to work right.

 Section 11. Questions applicable to very out-of-date software
 Q11.1       Emacs just dumps core.
 Q11.2       fdisk says cannot use nnn sectors of this partition
 Q11.3       GCC sometimes uses huge amounts of virtual memory and thrashes
 Q11.4       My keyboard goes all funny after I switch VC's.

 Section 12. How to get further assistance
 Q12.1       You still haven't answered my question !
 Q12.2       What to put in a request for help
 Q12.3       I want to mail someone about my problem.

 Section 13. Administrative information and acknowledgements
 Q13.1       Feedback is invited
 Q13.2       Formats in which this FAQ is available
 Q13.3       Authorship and acknowledgements
 Q13.4       Disclaimer and Copyright

===============================================================================

Section 1.  Introduction and General Information

 Q1.1        What is twin ?
 Q1.2        Does it run on my computer ?
 Q1.3        Can twin display on X ? On Linux console ? On ... ?
 Q1.4        What software does it provide ? Which programs require twin ?
 Q1.5        What ports to other operating systems are there ?
 Q1.6        Is twin PD ?  Copyrighted ?

-------------------------------------------------------------------------------

Question 1.1.  What is twin ?

Twin is a windowing environment with mouse support, window manager,
terminal emulator and networked clients, all inside a text display.

You can think to twin as the text-mode equivalent of X11 servers,
with some extra features:

a) It manages multiple windows on a single screen,
   just like X11 servers except that twin uses text-mode.
   
b) It has X11-style networked server capabilities:
   programs started remotely can connect to twin using sockets,
   just like X11 clients (xterm, fvwm2, gimp, kde, netscape, ...) connect
   to X11 servers.

c) It has built-in window manager and terminal emulator (Linux console
   emulator, actually).

d) It supports a variety of displays by using specific drivers -
   see Q1.3 `Can twin use X11 to display ? And Linux console ? And ... ?'
   for more details.

e) It and can attach/detach displays on-the-fly and supports
   multiple simultaneous displays. You can find a very similar
   feature in VNC (Virtual Network Computer, a virtual X11 server).

   
Twin is distributed under the GNU General Public License - see
Q1.6 `Is twin PD ?  Copyrighted ?' for more details.
   
-------------------------------------------------------------------------------

Question 1.2.  Does it run on my computer ?

Twin has been tested to compile on various operating systems, including:
Linux (i386, PowerPC, Alpha, Sparc),
FreeBSD (i386),
SunOS.

The author had yet no chance to seriously test twin on other systems.
But having a compatible operating system is not enough, a supported display is
required too - see Q1.3 Can twin display on X ? On Linux console ? On ... ?

-------------------------------------------------------------------------------

Question 1.3.  Can twin display on X ? On Linux console ? On ... ?

In order to let the user see all the text-mode windows created by twin,
twin server must draw on a display using one of its display drivers.
At the time this document is being written, twin supports at least the
following drivers:

X [X11] : lets twin display on X11 servers (plain driver).
gfx     : lets twin display on X11 servers (enhanced driver).
twin    : lets twin display on another twin server or on itself.
tty     : lets twin display on text terminals, including at least:
	Linux console (mouse support requires gpm and libgpm)
	twterm, twin's own terminal emulator (with mouse)
	any termcap/ncurses compatible terminal (with mouse if they support
		either xterm or twterm mouse reporting protocols)
ggi     : lets twin use libggi as display (UNFINISHED)

-------------------------------------------------------------------------------

Question 1.4.  What software does it provide ? Which programs require twin ?

Twin is distributed with:

a) twin server (obvious)
b) twattach and twdisplay - utilities to attach/detach displays
c) various more-or-less useful utilities, including at least:
   twcat, twclip, twlsobj, twevent, twfindtwin,
   twmapscrn, twsendmsg, twsetroot, twthreadtest.
d) some more complex clients, including at least:
   twsysmon - a system resources monitor (works on Linux only) 
   twterm   - a terminal emulator (Linux console emulator, actually)
   twdm     - a login manager, modeled after xdm/kdm.

To obtain more information about these clients, see the Tutorial.
   
Various libraries come with twin too:

e) libTutf  - a tiny unicode translation library
f) libTw    - a library to talk to twin servers
g) libTT    - a text toolkit library




===============================================================================

Section 13.  Administrative information and acknowledgements

 Q13.1       Feedback is invited
 Q13.2       Formats in which this FAQ is available
 Q13.3       Authorship and acknowledgements
 Q13.4       Disclaimer and Copyright

-------------------------------------------------------------------------------

Question 13.1.  Feedback is invited

Please send me your comments on this FAQ.

I accept submissions for the FAQ in any format;  All contributions
comments and corrections are gratefully received.

Please send them to <ijackson@gnu.ai.mit.edu>.

If you wish to refer to a question(s) in the FAQ it's most useful for me
if you do so by the question heading, rather than the number, as the
question numbers are generated automatically and I don't see them in the
source file I edit.

I prefer comments in English to patchfiles - I write the FAQ in a
different internal format anyway, so I can't use a patchfile.

-------------------------------------------------------------------------------

Question 13.2.  Formats in which this FAQ is available

This document is available as an ASCII text file, an Emacs Info document,
an HTML World Wide Web page, PostScript and as a USENET news posting.

The ASCII, Emacs Info, HTML and posted versions and a Lout typesetter file
(from which the PostScript is produced) are generated automatically by a
Perl script which takes as input a file in the Bizarre Format with No
Name.

The output files linux-faq.ascii, .info and .ps and a tarfile
linux-faq.source.tar.gz, containing the BFNN source and Perl script
converter, are available in the docs directories of the major Linux FTP
sites.

The HTML version of this FAQ is available as
http://www.cl.cam.ac.uk/users/iwj10/linux-faq/index.html and is mirrored
at www.li.org and other sites.

The USENET version is posted regularly to comp.os.linux.announce,
comp.os.linux.answers, comp.answers and news.answers.

-------------------------------------------------------------------------------

Question 13.3.  Authorship and acknowledgements

This FAQ was compiled by Ian Jackson <ijackson@gnu.ai.mit.edu>, with
assistance and comments from others too numerous to mention.

Special thanks are due to Matt Welsh, who moderated comp.os.linux.announce
and comp.os.linux.answers, used to coordinate the HOWTOs and has written
substantial portions of many of them, to Greg Hankins, who currently
coordinates the HOWTOS, to Lars Wirzenius, who currently moderates
comp.os.linux.announce, and to Marc-Michel Corsini, who wrote the original
Linux FAQ.

Thanks also to the many people who have sent comments and suggestions;
they are too numerous to list here, but their input has been invaluable.

Last but not least, thanks to Linus Torvalds and the other contributors to
Linux for giving us something to write about !

-------------------------------------------------------------------------------

Question 13.4.  Disclaimer and Copyright

Note that this document is provided as is.  The information in it is *not*
warranted to be correct; you use it at your own risk.

Linux Frequently Asked Questions with Answers is Copyright 1994, 1995,
1996 by Ian Jackson <ijackson@gnu.ai.mit.edu>.

It may be reproduced and distributed in its entirety (including this
authorship, copyright and permission notice) provided that either:

* the distribution is not commercial (commercial means any situation in
  which you benefit financially - directly or indirectly such as by
  inclusion in a publication which carries commercial advertising), or
* the distribution is in machine-readable form (ie, a form intended to be
  easily processed by a computer).

Note that this restriction is not intended to prohibit charging for the
service of printing or copying a document supplied by your customer.

Any distribution of a partial copy or extract, a translation or a
derivative work must be approved by me before distribution.  Email me -
I'll probably be happy to oblige !

Exceptions to these rules may be granted, and I shall be happy to answer
any questions about this copyright --- write to Ian Jackson, Churchill
College, Cambridge, CB3 0DS, United Kingdom or email
<ijackson@gnu.ai.mit.edu>.  These restrictions are here to protect the
contributors, not to restrict you as educators and learners.

Ian Jackson asserts the right to be identified as the author of this work,
and claims the moral rights of paternity and integrity, in accordance with
the Copyright, Designs and Patents Act, 1988.

