Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Programming
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Databases
Mail Systems
openSolaris
Eclipse Documentation
Techotopia.com
Virtuatopia.com

How To Guides
Virtualization
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Windows
Problem Solutions
Privacy Policy

  




 

 

The sed FAQ
Prev Home Next

3.1.3. Substitution switches

Standard versions of sed support 4 main flags or switches which may be added to the end of an "s///" command. They are:

       N      - Replace the Nth match of the pattern on the LHS, where
                N is an integer between 1 and 512. If N is omitted,
                the default is to replace the first match only.
       g      - Global replace of all matches to the pattern.
       p      - Print the results to stdout, even if -n switch is used.
       w file - Write the pattern space to 'file' if a replacement was
                done. If the file already exists when the script is
                executed, it is overwritten. During script execution,
                w appends to the file for each match.

GNU sed 3.02 and ssed also offer the /I switch for doing a case-insensitive match. For example,

     echo ONE TWO | gsed "s/one/unos/I"      # prints "unos TWO"

GNU sed 4.x and ssed add the /M switch, to simplify working with multi-line patterns: when it is used, ^ or $ will match BOL or EOL. \` and \' remain available to match the start and end of pattern space, respectively.

ssed supports two more switches, /S and /X, when its Perl mode is used. They are described in detail in section 6.7.3.H, below.

The sed FAQ
Prev Home Next

 
 
   Reprinted courtesy of Eric Pement. Also available at https://sed.sourceforge.net/sedfaq.html Design by Interspire