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SED FAQ CONTENTS:
1. GENERAL INFORMATION

• 1.1. Introduction - How this FAQ is organized
• 1.2. Latest version of the sed FAQ
• 1.3. FAQ revision information
• 1.4. How do I add a question/answer to the sed FAQ?
• 1.5. FAQ abbreviations
• 1.6. Credits and acknowledgements
• 1.7. Standard disclaimers

2. BASIC SED

• 2.1. What is sed?
• 2.2. What versions of sed are there, and where can I get them?

2.2.1. Free versions

• 2.2.1.1. Unix platforms
• 2.2.1.2. OS/2
• 2.2.1.3. Microsoft Windows (Win3x, Win9x, WinNT, Win2K)
• 2.2.1.4. MS-DOS
• 2.2.1.5. CP/M

2.2.2. Shareware and Commercial versions

• 2.2.2.1. Unix platforms
• 2.2.2.2. OS/2
• 2.2.2.3. Windows 95/98, Windows NT, Windows 2000
• 2.2.2.4. MS-DOS

2.3. Where can I learn to use sed?

• 2.3.1. Books
• 2.3.2. Mailing list
• 2.3.3. Tutorials, electronic text
• 2.3.4. General web and ftp sites

3. TECHNICAL

• 3.1. More detailed explanation of basic sed
• 3.2. Common one-line sed scripts. How do I . . . ?
• 3.3. Addressing and address ranges
• 3.4. [reserved]
• 3.5. [reserved]
• 3.6. Notes about s2p, the sed-to-perl translator
• 3.7. GNU/POSIX extensions to regular expressions

4. EXAMPLES

• 4.1. How do I perform a case-insensitive search?
• 4.2. How do I make changes in only part of a file?
• 4.3. How do I change only the first occurrence of a pattern?
• 4.4. How do I make substitutions in every file in a directory, or in a complete directory tree?

• 4.4.1 - Perl solution
• 4.4.2 - Unix solution
• 4.4.3 - DOS solution

• 4.5. How do I parse a comma-delimited data file?
• 4.6. How do I insert a newline into the RHS of a substitution?
• 4.7. How do I represent control-codes or non-printable characters?
• 4.8. How do I read environment variables with sed?

• 4.8.1. - on Unix platforms
• 4.8.2. - on MS-DOS or 4DOS platforms

• 4.9. How do I export or pass variables back into the environment?
• 4.9.1. - on Unix platforms
• 4.9.2. - on MS-DOS or 4DOS platforms

• 4.10. How do I handle shell quoting in sed?
• 4.11. How do I delete a block of text if the block contains a certain regular expression?
• 4.12. How do I locate/print a paragraph of text if the paragraph contains a certain regular expression?
• 4.13. How do I delete a block of _specific_ consecutive lines?
• 4.14. How do I read (insert/add) a file at the top of a textfile?
• 4.15. How do I address all the lines between RE1 and RE2, excluding the lines themselves?
• 4.16. How do I replace "/some/UNIX/path" in a substitution?
• 4.17. How do I replace "C:\SOME\DOS\PATH" in a substitution?
• 4.18. How do I convert files with toggle characters, like +this+, to look like [i]this[/i]?
• 4.19. How do I delete only the first occurrence of a pattern?
• 4.20. How do I commify a string of numbers?

5. WHY ISN'T THIS WORKING?

• 5.1. Why don't my variables like $var get expanded in my sed script?
• 5.2. I'm using 'p' to print, but I have duplicate lines sometimes.
• 5.3. Why does my DOS version of sed process a file part-way through and then quit?
• 5.4. My RE isn't matching/deleting what I want it to. (Or, "Greedy vs. stingy pattern matching")
• 5.5. What is CSDPMI*B.ZIP and why do I need it?
• 5.6. Where are the man pages for GNU sed?
• 5.7. How do I tell what version of sed I am using?
• 5.8. Does sed issue an exit code?
• 5.9. The 'r' command isn't inserting the file into the text.
• 5.10. Why can't I match or delete a newline using the \n escape sequence? Why can't I match 2 or more lines using \n?
• 5.11. My script aborts with an error message, "event not found".

6. OTHER ISSUES

• 6.1. I have a problem that stumps me. Where can I get help?
• 6.2. How does sed compare with awk, perl, and other utilities?
• 6.3. When should I use sed?
• 6.4. When should I NOT use sed?
• 6.5. When should I ignore sed and use Awk or Perl instead?
• 6.6. Known limitations among sed versions
• 6.6.1. Maximum line length
• 6.6.2. Maximum size for all buffers (pattern space + hold space)
• 6.6.3. Maximum number of files that can be read with read command
• 6.6.4. Maximum number of files that can be written with 'w' command
• 6.6.5. Limits on length of label names
• 6.6.6. Limits on length of write-file names
• 6.6.7. Limits on branch/jump commands

• 6.7. Known bugs among sed versions

• 6.8. Known incompatibilities between sed versions
• 6.8.1. Issuing commands from the command line
• 6.8.2. Using comments (prefixed by the '#' sign)
• 6.8.3. Special syntax in REs
• 6.8.4. Word boundaries
• 6.8.5. Range addressing with GNU sed and HHsed
• 6.8.6. Commands which operate differently