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From: maart@cs.vu.nl (Maarten Litmaath)
Newsgroups: comp.unix.questions
Subject: Re: Help a novice: Will "sed" do?
Keywords: Automatic edits.  Sed.
Message-ID: <2895@solo8.cs.vu.nl>
Date: 17 Jul 89 18:35:19 GMT
References: <2180@umbc3.UMBC.EDU>
Organization: V.U. Informatica, Amsterdam, the Netherlands
Lines: 53

rostamia@umbc3.UMBC.EDU (Dr. Rouben Rostamian) writes:
\I need a command or a script that searches a text file for a given
\word or pattern and prints out all paragraphs that contain that word
\or pattern.  Paragraphs are blocks of text separated by one or 
\more blank lines.

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#!/bin/sh

test $# = 0 && {
	echo "Usage: `basename $0` <pattern> [<files>]" >&2
	exit 1
}

pattern=`echo "$1" | sed 's-/-\\\\/-g'`		# quote slashes in the pattern
shift

tab="`ctrl I`"		# if you don't have `ctrl': tab="	" (a hard tab)
empty="^[ $tab]*$"	# the pattern of an `empty' line

SED="
: gap
	/$empty/!b para
: gap1
	n
	b gap
: para
	/$pattern/b found
	H
	n
	/$empty/!b para
: cleanup
	s/.*//
	x
	b gap1
: found
	H
	\${
		g
		p
	}
	n
	/$empty/!b found
	g
	p
	b cleanup
"

sed -n "$SED" $*
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-- 
   "... a lap-top Cray-2 with builtin    |Maarten Litmaath @ VU Amsterdam:
cold fusion power supply"  (Colin Dente) |maart@cs.vu.nl, mcvax!botter!maart