sed not working

UNIX for Advanced & Expert Users
1

Hi,

Iam doing the following using sed in a script , it is NOT working

line_old= 3754|Yes|Yes
line_new= 3754|Yes|Yes|Yes|Yes

sed -e 's/$line_old/$line_new/' data.$$ > tmp.$$
mv tmp.$$ data.$$

Regards

2

Drop the single quotes and introduce double quotes.

3

Vino,

It was an interesting thing to know about, can you pls explain the logic behind.

Regards,
Tayyab

4

It worked thanks

5

See the section QUOTING under man sh. Its too big to quote here. But this is what you are looking for..

       Enclosing  characters  in  double quotes preserves the literal value of
       all characters within the quotes, with the exception of $,  `,  and  \.
       The  characters  $  and  `  retain  their special meaning within double
       quotes.  The backslash retains its special meaning only  when  followed
       by one of the following characters: $, `, ", \, or <newline>.  A double
       quote may be quoted within double quotes by preceding it with  a  back-
       slash.
6

Vino, thanks for your reply. I know a double quote is used to preserve the literal value of characters, thing of interest was difference between single and double quote.