sed is short for "stream editor", originally developed by Lee McMahon? on Unix in 1973 or 1974.
Author: Lee McMahon? Homepage: http://sed.sourceforge.net Family: BellLabsFamily Platform: Unix, Linux, BSD, AIX, HP-UX, MS-DOS, Windows, Mac OS/X, others. License: Open Source
It has been ported to DOS, Windows, Macintosh, CP/M, and other operating systems.
sed is a lot like using VI in OpenMode. sed is a non-interactive editor. sed is a command-line utility, meaning that it is called from a command or shell prompt, taking its input from the output of a pipe or from a file on disk, and sending its output to stdout (the screen). The user must save changes to the disk by using the redirection arrow (>) or use the -i switch available in newer versions of sed. sed requires a script of editing commands to delete, insert, append, or change whole lines, or ranges of lines. The editing commands may be in an external script file, or passed as parameters on the command line. The most frequently-used sed command is the substitution command, which can change one or more occurrences of a given pattern on a line.
The strength of sed comes from its use of "regular expressions" (or regexes), so that variant spellings, capitalizations, or positions within a word or character string can be matched and changed as needed.
Sed is commonly called from within scripts to perform unattended "batch" edits on files.
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