Linux Frequently Asked Questions with Answers

Robert Kiesling

rkiesling@mainmatter.com

Revision History
Revision 1.112001-08-12Revised by: rk
$Revision: 1.11 $

This is the list of Frequently Asked Questions for Linux, the free operating system kernel that runs on many modern computer systems. The kernel source code documentation says that Linux ``aims for POSIX compliance.'' Linux uses mostly free, GNU system utilities and application software, although commercial programs are available also. Originally written for 386/486/586 Intel/ISA bus machines, Linux versions exist for nearly every hardware platform in existence that is capable of running it. (Please refer to the question, ``What Is Linux?'' below.) This FAQ is meant to be read in conjunction with the Linux Documentation Project's HOWTO series. (``Where Are the Linux FTP Archives?'' and, ``Where Is the Documentation?'') The INFO-SHEET and META-FAQ also list sources of Linux information. Please read them, and, ``If this Document Still Hasn't Answered Your Question....'' before posting to a Usenet news group. You can also get Postscript, PDF, HTML, and SGML versions of this document. (``Formats in Which This FAQ Is Available.'')

Table of Contents
1. Introduction and General Information
1.1. What Is Linux?
1.2. How to Get Started.
1.3. What Software does Linux Support?
1.4. How to Find a Particular Application.
1.5. What Hardware Is Supported?
1.6. Ports to Other Processors.
1.7. Disk Space Requirements: Minimal, Server, and Workstation.
1.8. Minimum and Maximum Memory Requirements.
1.9. Does Linux Support Universal System Bus Devices?
1.10. What Is Linux's Open-Source License?
1.11. Is Linux *nix?
2. Topics of Current Interest.
2.1. What Is the Best Way to Respond to Anti-Linux FUD?
2.2. What Is the Status of the Charges against Dmitri Skylarov? What Is the Status of Information about PDF Decryption?
2.3. What Resources Are Available for Linux DeCSS and Other Open Source DVD Software?
2.4. Where Is Information About Electronic Privacy Laws that Affect ISP's?
3. Network Sources and Resources
3.1. Where Is the Latest Kernel Version on the Internet?
3.2. Where Is the Documentation?
3.3. Where Is the Linux Stuff on the World Wide Web?
3.4. What News Groups Are There for Linux?
3.5. What Other FAQ's and Documentation Are There for Linux?
3.6. Where Are the Linux FTP Archives?
3.7. How To Get Linux without FTP Access.
3.8. How To Get Information without Usenet Access.
3.9. What Mailing Lists Are There?
3.10. Where Are Linux Legal Issues Discussed?
3.11. Sources of Information for Unmaintained Free Software Projects.
3.12. Are the News Groups Archived Anywhere?
3.13. Where To Find Information About Security Related Issues.
3.14. Where To Find Linux System Specifications.
4. Compatibility with Other Operating Systems
4.1. Can Linux Use the Same Hard Drive as MS-DOS? OS/2? 386BSD? Win95?
4.2. How To Access Files on a MS-DOS Partition or Floppy.
4.3. Does Linux Support Compressed Ext2 File Systems?
4.4. Can Linux Use Stacked/DBLSPC/Etc. DOS Drives?
4.5. Can Linux Access OS/2 HPFS Partitions?
4.6. Can Linux Access Amiga File Systems?
4.7. Can Linux Access BSD, SysV, Etc. UFS?
4.8. Can Linux Access SMB File Systems?
4.9. Can Linux Access Macintosh File Systems?
4.10. Can Linux Run Microsoft Windows Programs?
4.11. Where Is Information about NFS Compatibility?
4.12. Can Linux Use True Type Fonts?
4.13. Can Linux Boot from MS-DOS?
4.14. How Can Linux Boot from OS/2's Boot Manager?
5. File Systems, Disks, and Drives
5.1. How To Get Linux to Work with a Disk.
5.2. How To Undelete Files.
5.3. How To Make Backups.
5.4. How To Resize a Partition (Non-Destructively).
5.5. Is There a Defragmenter for Ext2fs?
5.6. How To Create a File System on a Floppy.
5.7. Does Linux Support Virtualized File Systems Like RAID?
5.8. Does Linux Support File System Encryption?
5.9. Linux Prints Nasty Messages about Inodes, Blocks, and the Like.
5.10. The Swap Area Isn't Working.
5.11. How To Add Temporary Swap Space.
5.12. How To Remove LILO So the System Boots DOS Again?
5.13. Why Does fdformat Require Superuser Privileges?
5.14. The System Checks the Ext2fs Partitions Each Reboot.
5.15. Root File System Is Read-Only.
5.16. What Is /proc/kcore?
5.17. The AHA1542C Doesn't Work with Linux.
5.18. Where Is the Journalling File System on the Net?
6. Porting, Compiling and Obtaining Programs
6.1. How To Compile Programs.
6.2. How To Install GNU Software.
6.3. Where To Get Java.
6.4. How To Port XXX to Linux.
6.5. What Is ld.so and How To Get It?
6.6. How To Upgrade the Libraries without Trashing the System.
6.7. How To Use Code or a Compiler Compiled for a 486 on a 386.
6.8. What Does ``gcc -O6'' Do?
6.9. Where Are linux/*.h and asm/*.h?
6.10. What To Do about Errors Trying to Compile the Kernel.
6.11. How To Make a Shared Library.
6.12. Programs Are Very Large.
6.13. Does Linux Support Threads or Lightweight Processes?
6.14. Where To Find lint for Linux.
6.15. Where To Find Kermit for Linux.
6.16. How To Use Linux with a Cable Modem.
6.17. Is There an ICQ Program That Runs under Linux?
7. Solutions to Common Miscellaneous Problems
7.1. FTP Transfers Seem to Hang.
7.2. Free Dumps Core.
7.3. Netscape Crashes Frequently.
7.4. FTP or Telnet Server Won't Allow Logins.
7.5. How To Keep Track of Bookmarks in Netscape?
7.6. The Computer Has the Wrong Time.
7.7. Setuid Scripts Don't Seem to Work.
7.8. Free Memory as Reported by free Keeps Shrinking.
7.9. When Adding More Memory, the System Slows to a Crawl.
7.10. Some Programs (E.g. xdm) Won't Allow Logins.
7.11. Some Programs Allow Logins with No Password.
7.12. The Machine Runs Very Slowly with GCC / X / ...
7.13. System Only Allows Root Logins.
7.14. The Screen Is All Full of Weird Characters Instead of Letters.
7.15. I Screwed Up the System and Can't Log In to Fix It.
7.16. I Forgot the root Password.
7.17. There's a Huge Security Hole in rm!
7.18. lpr and/or lpd Don't Work.
7.19. Timestamps on Files on MS-DOS Partitions Are Set Incorrectly
7.20. How To Get LILO to Boot the Kernel Image.
7.21. How To Make Sure the System Boots after Re-Installing the Operating System.
7.22. The PCMCIA Card Doesn't Work after Upgrading the Kernel.
7.23. How To Remove (or Change) the Colors in the ls Display.
7.24. Why Won't a Program Work in the Current Directory?
8. How To Do This or Find Out That...
8.1. How To Find Out If a Notebook Runs Linux.
8.2. Installing Linux Using FTP.
8.3. Resuming an Interrupted Download.
8.4. Boot-Time Configuration.
8.5. Formatting Man Pages without man or groff.
8.6. How To Scroll Backwards in Text Mode.
8.7. How To Get Email to Work.
8.8. Sendmail Pauses for Up to a Minute at Each Command.
8.9. How To Enable and Select Virtual Consoles.
8.10. How To Set the Time Zone.
8.11. Dial-up PPP Configuration.
8.12. What Version of Linux and What Machine Name Is This?
8.13. What Is a ``core'' File?
8.14. How To Enable or Disable Core Dumps.
8.15. How To Upgrade/Recompile a Kernel.
8.16. Can Linux Use More than 3 Serial Ports by Sharing Interrupts?
8.17. Configuring Emacs's Default Settings.
8.18. How To Make a Rescue Floppy.
8.19. How To Remap a Keyboard to UK, French, Etc.?
8.20. How To Get NUM LOCK to Default to On.
8.21. How To Set (Or Reset) Initial Terminal Colors.
8.22. How To Have More Than 128Mb of Swap.
9. Miscellaneous Information and Questions Answered
9.1. How To Program XYZ Under Linux.
9.2. What's All This about ELF? glibc?
9.3. How To Determine What Packages Are Installed on a System.
9.4. What Is a .gz File? And a .tgz? And .bz2? And... ?
9.5. What Does VFS Stand For?
9.6. What is a BogoMip?
9.7. What Online/Free Periodicals Exist for Linux?
9.8. How Many People Use Linux?
9.9. How Many People Use Linux? (Redux.)
9.10. What Is the Best (Distribution|SCSI Card|Editor|CD-ROM Drive|....)
9.11. How Does One Pronounce Linux?
10. Frequently Encountered Error Messages
10.1. Modprobe Can't Locate Module, XXX, and Similar Messages.
10.2. Unknown Terminal Type ``linux'' and Similar.
10.3. INET: Warning: old style ioctl... called!
10.4. ld: unrecognized option '-m486'
10.5. GCC Says, ``Internal compiler error.''
10.6. Make Says, ``Error 139.''
10.7. Shell-Init: Permission Denied when I Log In.
10.8. No Utmp Entry. You Must Exec ... when Logging In.
10.9. Warning--bdflush Not Running.
10.10. Warning: obsolete routing request made.
10.11. EXT2-fs: warning: mounting unchecked file system.
10.12. EXT2-fs warning: maximal count reached.
10.13. EXT2-fs warning: checktime reached.
10.14. df Says, ``Cannot read table of mounted file systems.''
10.15. fdisk Says, ``Partition X has different physical/logical...''
10.16. fdisk: Partition 1 does not start on cylinder boundary.
10.17. fdisk Says Partition n Has an Odd Number of Sectors.
10.18. A Mtools Utility Says It Cannot Initialize Drive XYZ.
10.19. At the Start of Booting: Memory tight
10.20. The System Log says, ``end_request: I/O error, ....''
10.21. ``You don't exist. Go away.''
10.22. ``Operation not permitted.''
10.23. programname: error in loading shared libraries: lib xxx..so. x: cannot open shared object file: No such file or directory.
10.24. ``init: Id "x" respawning too fast: disabled for 5 minutes.''
10.25. FTP server says: ``421 service not available, remote server has closed connection.''
11. The X Window System
11.1. Does Linux Support X?
11.2. How To Get the X Window System to Work.
11.3. Where To Find a Ready-Made XF86Config file.
11.4. What Desktop Environments Run on Linux?
11.5. xterm Logins Show Up Strangely in who, finger.
12. How to Get Further Assistance
12.1. If this Document Still Hasn't Answered Your Question....
12.2. What to Put in a Request for Help.
12.3. How To Email Someone about Your Problem.
13. Acknowledgments and Administrivia
13.1. Where To Send Comments.
13.2. Formats in Which This FAQ Is Available.
13.3. Authorship and Acknowledgments.
13.4. Disclaimer and Copyright.
  Next
  Introduction and General Information