Use grep to search for word / string of text and include lines before and after

For BSD or GNU grep you can use -B num to set how many lines before the match and -A num for the number of lines after the match.

grep -B 3 -A 2 foo README.txt

If you want the same amount of lines before and after you can use -C num.

grep -C 3 foo README.txt

This will show 3 lines before and 3 lines after.

 

In Solaris, there is a less simple solution since grep doesn't support this on this OS:

 

Code:

nawk '$0~s{for(c=NR-b;c<=NR+a;c++)r[c]=1}{q[NR]=$0}END{for(c=1;c<=NR;c++)if(r[c])print q[c]}' b=2 a=4 s="string" file1

...where "b" and "a" are the number of lines to print before and after string "s".