Shell Programming and Scripting

Hi,

I am modifying a file with sed command. i want to make SCORE= blank in the file whereever SCORE=somevalue.

What will *$ do in the below command?

Code:

cat $file | sed 's/SCORE=.*$/SCORE=\r/g' > newfile

The last line is also missing in the new file. How to make SCORE='100' to SCORE= blank in a file

What is the use of $ in sed command?

Thanks
Ashok

$ means "must match until the end of the line". .* means "match zero or more of any character". a* would mean "match 1 or more a's".

So

Code:

's/SCORE=.*$/SCORE=\r/g

means match SCORE (at any point in the line) plus zero or more characters, until the end of the line, and replace it with SCORE=\r. The /g tells it to do so multiple times on each line if there's more than one match, but if you're matching everything after SCORE= that's probably redundant.

Why the \r? That might be confusing the output since, when printed in a terminal, it will return to the beginning of the line without moving down one line, making it look like it's been deleted.

Hi,

Thanks for your reply. Below is the content of my file. How to replace SCCORE=somevalue to SCORE=blank in all the places in the file.

Please note that SCORE will have different values at different places?

How too use sed command to replace SCORE=somevalue?

Code:

[KEY A]
TABLE=TableA
KEY=KEYA
DESC=VALUE
ORDERBY=Id
SCORE=C:\Common\TestscoreA
[KEY B]
TABLE=TableB
KEY=KEYA
DESC=VALUE
ORDERBY=Id
SCORE=C:\Common\TestscoreB
[KEY C]
TABLE=TableA
KEY=KEYA
DESC=VALUE
ORDERBY=Id
SCORE=C:\Common\TestscoreC

Thanks
Ashok

should be good enough with

Code:

sed 's/SCORE=.*/SCORE=/'

You're welcome. You might want to read it too.

Code:

cat $file | sed 's/SCORE=.*$/SCORE=\r/g' > newfile

Code:

cat $file | sed 's/SCORE=.*$/SCORE=/' > newfile

That's also a useless use of cat, by the way, so:

Code:

sed 's/SCORE=.*$/SCORE=/' < "$file" > newfile

awk alternative.

Code:

awk '$0 ~ /^SCORE=/ { $0="SCORE=" } 1' scores.txt >newfile