[SOLVED] cut username only from a file with sed

freeroute · 08-12-2017, 11:59 PM

I have a large file with this format: e-mail:hash:ID

e.g.:

Quote:

user1@yahoo.com:2fb6c56e97b68ea6d4286349062cc457:ID1
user2@gmail.com:5249b8cddf50e28cbe0e2c351afa37d8:ID2
user3@cox.net:fa9797f0463ebd4e3e90bf5e908f40d8:ID3

I would like to cut the username from the mail field.

Desired output:
user1
user2
user3

How could I do it with sed?

My bad command:

Code:

sed -np '/^*@/p' file.txt

I can do it with the cut command:

Quote:

cut -d@ -f 1 file

Thank you very much.

syg00 · 08-13-2017, 12:24 AM

You have "cut", so this is self education on sed ?.
You need to use the "s" command of sed - well documented. In this case I might be inclined to delete the @ and everything after it, but the choice is yours.

freeroute · 08-13-2017, 12:26 AM

Quote:

Originally Posted by syg00

You have "cut", so this is self education on sed ?.
You need to use the "s" command of sed - well documented. In this case I might be inclined to delete the @ and everything after it, but the choice is yours.

Yes, self education only.
I am learning sed...

Thank you.

syg00 · 08-13-2017, 12:35 AM

Start here - go down to docs and get the info file; handy to have on your machine.
Also have a look at the 1liners file for ideas of how to do things with sed.

AwesomeMachine · 08-13-2017, 12:36 AM

You would use:

Code:

$ sed 's/@.*//g' file1 > file2

where file1 is the input file and file2 is the output file.

freeroute · 08-13-2017, 12:51 AM

Quote:

Originally Posted by AwesomeMachine

You would use:

Code:

$ sed 's/@.*//g' file1 > file2

where file1 is the input file and file2 is the output file.

Thank you. It works.

I understand that s means substitute, g means global.
Your command means: Substitute characters in lines by lines with nothing which contains @ character, followed any character (.*), and than print matchings?

pan64 · 08-13-2017, 03:05 AM

sed will process file line by line (in your case it is a substitution) and also will print the result. This is the default behavior, no need to match anything.

AwesomeMachine · 08-13-2017, 05:25 AM

The substitution expression means substitute nothing in place @ followed by any number of single characters.