Grep a string in a range and delete the line

Shell Programming and Scripting
1

Hi,

i need to delete a lines after searching a particular string but this searching should only happen after the 4th line..

basically imagine a file like this

From: abcd.yahoo.com
To: cdeb.yahoo.com
Subject: hi all
sdfsd
sadasd
asdasd
dfsdf
From: abcd.yahoo.com
To: cdeb.yahoo.com
Subject: hi all
asdfasdf
asdfasdf
dsghsdfg
hjhdfg

and i need the ouput like this

From: abcd.yahoo.com
To: cdeb.yahoo.com
Subject: hi all
sdfsd
sadasd
asdasd
dfsdf
asdfasdf
asdfasdf
dsghsdfg
hjhdfg

how do i do this either grep or sed or awk.. please help..

2

try..

-bash-3.2$ sed '8,10d' file
From: abcd.yahoo.com
To: cdeb.yahoo.com
Subject: hi all
sdfsd
sadasd
asdasd
dfsdf
asdfasdf
asdfasdf
dsghsdfg
hjhdfg
-bash-3.2$
3

The following command removes header lines (From, To, Subject) after the 4th line :

awk 'NR>4 && /^(From|To|Subject):/ {next} 1' inputfile

Inputfile:

From: abcd.yahoo.com
To: cdeb.yahoo.com
Subject: hi all
1-sdfsd
1-sadasd
1-asdasd
1-dfsdf 
From: abcd.yahoo.com
To: cdeb.yahoo.com
Subject: hi all
2-asdfasdf
2-asdfasdf
2-dsghsdfg
2-hjhdfg

Output:

From: abcd.yahoo.com
To: cdeb.yahoo.com
Subject: hi all
1-sdfsd
1-sadasd
1-asdasd
1-dfsdf 
2-asdfasdf
2-asdfasdf
2-dsghsdfg
2-hjhdfg

Jean-Pierre.

4 
sed '4,${
	/From/{
	N
	N
	d
	}
}'