Linux in a Nutshell, Fifth Edition

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Chapter 10: The sed Editor

This is the Title of the Book, eMatter Edition

Copyright © 2006 O’Reilly & Associates, Inc. All rights reserved.

Branching Commands

Multiline Input Processing

Alphabetical Summary of sed Commands

GNU sed lets you use the filenames /dev/stdin, /dev/stdout and /dev/stderr to refer

to standard input, output, and error, respectively, for the r, R, w, and W

commands and the w flag to the s command.

GNU-specific commands or extensions are noted with {G} in the command

synopsis. When the GNU version allows a command to have two addresses, the

command is performed for each input line within the range.

#

#

Begin a comment in a sed script. Valid only as the first character of

the first line. (Some versions, including GNU sed, allow comments

anywhere, but it is better not to rely on this.) If the first line of the

script is #n, sed behaves as if -n had been specified.

:

:label

Label a line in the script for the transfer of control by b or t.

According to POSIX, sed must support labels that are unique in the

first eight characters. GNU sed has no limit, but some older

versions support up to only seven characters.

=

[/pattern/]=

[address1[,address2]]= {G}

Write to standard output the line number of each line addressed by

pattern.

Command Action

b Branch to label or to end of script.

t Same as b, but branch only after substitution.

T† Same as t, but branch only if no successful substitutions. ...