Question

it’s me again. I am encountering another problem
First i need to match a certain pattern ,For example:

dfsdf
sdfd
sdfs
sdf
vcv
ssdff
sdfdsf
adssa

i need to match sdf , then i need to delete the following lines of a fixed number (eg.3DD)
can i use the vi command in bash programming? Or are there any way to acheive it ?thanks again

Answer 1

Again, sed comes to the rescue! To work on the lines following a match:

sed "/^sdf$/,+3 d" file

This will remove the matching line, and the three following it. Just change the 3 to any number of lines you want to remove. Also, note that this will happen for every occurence of “sdf” in the input.

Just realized I might have misread the question. If you do not want to remove the matching line (“sdf” in this case), you can do like this:

sed "/^sdf$/,+3 {/^sdf$/b skip; d; :skip}" file