Info Catalog sed: Invoking sed sed: Command-Line Options

sed: Overview

 
 2.1 Overview
 ============
 
 Normally 'sed' is invoked like this:
 
      sed SCRIPT INPUTFILE...
 
    For example, to replace all occurrences of 'hello' to 'world' in the
 file 'input.txt':
 
      sed 's/hello/world/' input.txt > output.txt
 
    If you do not specify INPUTFILE, or if INPUTFILE is '-', 'sed'
 filters the contents of the standard input.  The following commands are
 equivalent:
 
      sed 's/hello/world/' input.txt > output.txt
      sed 's/hello/world/' < input.txt > output.txt
      cat input.txt | sed 's/hello/world/' - > output.txt
 
    'sed' writes output to standard output.  Use '-i' to edit files
 in-place instead of printing to standard output.  See also the 'W' and
 's///w' commands for writing output to other files.  The following
 command modifies 'file.txt' and does not produce any output:
 
      sed -i 's/hello/world/' file.txt
 
    By default 'sed' prints all processed input (except input that has
 been modified/deleted by commands such as 'd').  Use '-n' to suppress
 output, and the 'p' command to print specific lines.  The following
 command prints only line 45 of the input file:
 
      sed -n '45p' file.txt
 
    'sed' treats multiple input files as one long stream.  The following
 example prints the first line of the first file ('one.txt') and the last
 line of the last file ('three.txt').  Use '-s' to reverse this behavior.
 
      sed -n  '1p ; $p' one.txt two.txt three.txt
 
    Without '-e' or '-f' options, 'sed' uses the first non-option
 parameter as the SCRIPT, and the following non-option parameters as
 input files.  If '-e' or '-f' options are used to specify a SCRIPT, all
 non-option parameters are taken as input files.  Options '-e' and '-f'
 can be combined, and can appear multiple times (in which case the final
 effective SCRIPT will be concatenation of all the individual SCRIPTs).
 
    The following examples are equivalent:
 
      sed 's/hello/world/' input.txt > output.txt
 
      sed -e 's/hello/world/' input.txt > output.txt
      sed --expression='s/hello/world/' input.txt > output.txt
 
      echo 's/hello/world/' > myscript.sed
      sed -f myscript.sed input.txt > output.txt
      sed --file=myscript.sed input.txt > output.txt
 

Info Catalog sed: Invoking sed sed: Command-Line Options