Anyone know how to use SED to append a comma to the end of each line

example:

field1,field2,field3,field4

If i Cat /textfile ---- How can i append the end of /textfile with a comman?

echo 'a,b,c' | sed 's/$/,/'

Works Great...Thanks for your help

can u explain the syntax a little bit
about 'a,b,c' part

a,b,c is just a placeholder. It can be anything; wrt the OP, it is the same as
field1,field2,field3,field4

I am not sure if I have to start another thread or request for an answer in the same thread..

Just wondering how we can append tabs at the end of each line...
Data:
field1, field2, field3, field4
1 2
3 4 5

Append tab on field3 and field4 for the first row..and
Append tab on field4 for the second row.

Please advise...
Madhu

Not quite sure what you're saying, but assuming you have a datafile that contains:

1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5

and you want it formatted as you've shown, you could do:
awk '{print $1, $2"\n"$3, $4, $5"\n\n"}' <datafile>

to get:
1 2
3 4 5

1 2
3 4 5
etc.

The above could also be accomplished with "awk '{printf}'".

I can't see the usefulness of adding tabs to the end of each line unless you plan to paste a file to this one, but you can do:
sed 's/$/[press TAB button here]/' datafile > newfile