Are there any sed scripts built in to mainstream Linux distros?

Question

When I was studying bash, I found it very helpful to go and study the bash scripts already present on a clean install of Linux—/etc/profile, for instance, and anything in /etc/rc.d/init.d/. These are often quite advanced scripts, and by studying them I ensured I learned about many obscure features not covered in most bash tutorials.

I am studying sed now, and although the list of sed features is much shorter (so I know for a fact I have studied all of the features), I still feel it would be very beneficial to study through some sed scripts that are actually used in production, and are not just examples in tutorials.

To that end, I would really like to study any sed scripts that are already present on a well-known Linux distro, such as Ubuntu or CentOS. Trouble is, I have no idea where such scripts might be. I've already tried file /bin/* | grep script | sed 's/:.*//' | xargs grep sed with no results. file /sbin/* | grep script | sed 's/:.*//' | xargs grep -c sed returns some results, and I'm looking through those, but all the ones I have checked so far are just sed one-liners embedded in bash or sh scripts.

Where can I find some actual sed scripts on my Linux machine? Or failing that, is there a good place online to find some sed scripts that are actually used in production? (Reading through sedtris won't help much for my purposes. ;)

what you're asking for typically doesn't exist except, as you've already discovered, as one-liners in sh or bash scripts. see also http://unix.stackexchange.com/questions/2434/is-there-a-basic-tutorial-for-grep-awk-and-sed — cas, Oct 24 '15 at 04:02
I don't believe people are insane enough to write entire scripts in sed. (Not in a mainstream distro, anyway.) — muru, Oct 24 '15 at 04:39
ive always found sedtris edifying. if you have GNU sed, you can look at some of the scripts in info sed. you could look at math.sed. i seriously doubt youll find any examples worth following in any scripts distributed by default with linux distributions. you would find some, though, if you looked hard at a BSD Ports tree and its constituent makefiles. — mikeserv, Oct 24 '15 at 06:40

John1024 · Accepted Answer · 2015-10-24T05:37:30.450

3

Try:

grep -w sed /etc/init.d/*
grep -w sed /etc/grub.d/*
grep -w sed /usr/bin/*

The first yields 25 scripts and the second 47 on my system (debian).

The -w option restricts grep to looking for sed as a whole word. This way, matches to words like used or supposedly are avoided.

edited Oct 24 '15 at 05:37

answered Oct 24 '15 at 05:28

John1024

74,655

Thomas Dickey · Answer 2 · 2016-07-16T23:33:32.350

Rather than look in the operating system, look at scripts used for building the programs.

Any autoconf-generated configure script contains sed-scripts, and itself generates a script which contains a sed-script. That substitutes values for names in the template files such as Makefile.in to produce a Makefile. For example (conveniently found with web search) this chunk of a config.status file for distcc illustrates how sed is used:

    while :; do
      case $as_dir in #(
      *\'*) as_qdir=`$as_echo "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
      *) as_qdir=$as_dir;;
      esac
      as_dirs="'$as_qdir' $as_dirs"
      as_dir=`$as_dirname -- "$as_dir" ||
$as_expr X"$as_dir" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
     X"$as_dir" : 'X\(//\)[^/]' \| \
     X"$as_dir" : 'X\(//\)$' \| \
     X"$as_dir" : 'X\(/\)' \| . 2>/dev/null ||
$as_echo X"$as_dir" |
    sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
        s//\1/
        q
      }
      /^X\(\/\/\)[^/].*/{
        s//\1/
        q
      }
      /^X\(\/\/\)$/{
        s//\1/
        q
      }
      /^X\(\/\).*/{
        s//\1/
        q
      }
      s/.*/./; q'`
      test -d "$as_dir" && break
    done

Aside from autoconf, scripting is useful for other aspects of building (and installing) programs. The manlinks.sed script in ncurses is long enough to be considered as a program.

You can of course use grep to find sed used. However, it is common to use a ".sed" file-suffix for standalone scripts. "locate .sed" finds those.

In a quick check on my machine, there is one extremely long sed script (more than two thousand lines, counting comments):

#!/usr/5bin/sed -nf
#r
#r sokoban.sed - aurlio marinho jargas <aurelio@verde666.org>
#r Changes by Gunnar Ritter, October 2002.
#r
#r Sccsid @(#)sokoban.sed       1.7 (gritter) 10/12/03
#r
#r motivated by reading the amazing Adventure (Colossal Cave) history
#r      <http://www.rickadams.org/adventure/a_history.html>
#r GPL levels took from Mike Sharpe's sokoban.vim <http://vim.sourceforge.net>
#r
#r IMPORTANT
#r this script has terminal control chars, so you must DOWNLOAD this
#r file. just copy/paste or printing it to a file (lynx) will NOT work.
#r
#r THE GAME
#r you know sokoban. everybody knows sokoban.

(Someone made a colorized version of it).

That is one of three scripts used for testing sed in the "heirloom tools":

-rw-r--r--   1 tom           285 Oct  6 2002    makefile 
-rw-r--r--   1 tom          3664 Oct 11 2003    hanoi.sed
-rw-r--r--   1 tom          2338 Oct 11 2003    math.sed
-rw-r--r--   1 tom         42552 Oct 11 2003    sokoban.sed

Likewise, the sed program has an interesting example:

#!/bin/sed -nf
#  dc.sed - an arbitrary precision RPN calculator
#  Created by Greg Ubben <gsu@romulus.ncsc.mil> early 1995, late 1996
#
#  Dedicated to MAC's memory of the IBM 1620 ("CADET") computer.
#  @(#)GSU dc.sed 1.1 06-Mar-1999 [non-explanatory]
#
#  Examples:
#       sqrt(2) to 10 digits:   echo "10k 2vp" | dc.sed
#       20 factorial:           echo "[d1-d1<!*]s! 20l!xp" | dc.sed
#       sin(ln(7)):             echo "s(l(7))" | bc -c /usr/lib/lib.b | dc.sed
#       hex to base 60:         echo "60o16i 6B407.CAFE p" | dc.sed
#       tests most of dc.sed:   echo 16oAk2vp | dc.sed
#
#  To debug or analyze, give the dc Y command as input or add it to
#  embedded dc routines, or add the sed p command to the beginning of
#  the main loop or at various points in the low-level sed routines.
#  If you need to allow [|~] characters in the input, filter this
#  script through "tr '|~' '\36\37'" first (or use dc.pl).

Likewise, there is a page with a colorized version of dc.sed

However, autoconf and build-scripts are where you might find productive use of sed.

Are there any sed scripts built in to mainstream Linux distros?

3 Answers3