Deleting Lines Ending With a Full Stop Using SED

arnold.pietersen · 07-12-2012, 05:12 AM

Hi

How do I delete a line which ends with a full-stop? Sometimes there are two or even three full stops at the end.

It is a list of e-mail addresses.

Kind Regards

ARNOLD

pobrika · 07-12-2012, 05:36 AM

How about something like:

Code:

grep -v '\.$' filein.txt > fileout.txt

This will search the file filein.txt and only show output for files that do not end with a . (period) and output hte results into a file called fileout.txt

although this does not use sed

syg00 · 07-12-2012, 06:40 AM

And of course, something very similar will work with sed.

pobrika · 07-12-2012, 06:59 AM

If you must use sed then as syg00 said you can use sed in a similar fashion to grep -v as follows:

Code:

sed -n -e '/\.$/!p' filein.txt > fileout.txt

arnold.pietersen · 07-12-2012, 07:57 AM

Hi

Both methods work. Thank you.

Can you provide an explanation about some of the arguments. What I know is that:

1. '/ /' is standard notation
2. \.$ refers to the end of the line. Why does one have to use the \ could one not just have used .$
3. filein and fileout.

What does the others mean?

sed -n -e '/\.$/!p' filein.txt > fileout.txt

Once again, thank you.

Kind Regards

ARNOLD

grail · 07-12-2012, 07:59 AM

Or you could use the delete option for sed (//d)

grail · 07-12-2012, 08:01 AM

Quote:

2. \.$ refers to the end of the line. Why does one have to use the \ could one not just have used .$

A period matches any character so to refer to a period you need to escape it or place it in a character class ([])