Hi Guys!!!!!!!!!!

I have an input file


say

abcdef
123456
aaaaaa



i need to insert a line say "bbbbbb"
between abcdef and 123456


so that my o/p is

abcdef
bbbbbb
123456
aaaaaa

How to achieve it?
Thanks in advance

when i tried the following one:-

sed '/abcdef/a \bbbbb' your_file > your_file. the contents of your_file got deleted. why it was so.

You cannot change the contents of the file using sed but the output could be redirected to a new file. If you are going to redirect the same to the input file then it would result in a empty input file.

you can edit the same file with sed

using the " -i " option but that is available only as GNU sed option.

Thanks Guys!!!!!!!!!!!!!!!

But have a doubt ..
If suppose my input contains space...
For ex:

I/p File:

abc def
aaaaa
abc def
bbbbb


No i want to add the pattern 12345 after abc def so that my o/p file wil be


abc def
12345
abc def
bbbbb