Swap fields in a line of text

[alan147]

Good afternoon

I have a text file, part of the password file, it's format is

username:uid

I need to be able to reverse the output so that the uid is first i.e.

uid:username

Does anyone have a way of doing this? The suggestions from my office are to import it into excel !!!!!!

Thanks

Alan

 

[feherke]

Hi

sed 's/\(.*\):\(.*\)/\2:\1/' /input/file

Feherke.

http://rootshell.be/~feherke/

 

[alan147]

Thsnks very much.

Alan

 

[Annihilannic]

.*" does a "greedy" match so it would in fact match all of the line. in /etc/passwd up to the last ":".

I would recommend:

sed 's/\([^:]*\):\([^:]*\)/\2:\1/' /input/file

Although feherke probably correctly assumed that your existing file only has two fields anyway?

Annihilannic.

 

[alan147]

Hello

feherke did assume correctly, my file only had the username and uid in it.

However I now have another question. Now that the username and uid have been swapped I now need to extract those lines where the UID is identical, I know they should be unique but that is the purpose of this exercise.

Thanks


Alan

 

[Annihilannic]

[tt]sort -t: -k 1,1 filename | awk '$1==prev{print}{prev=$1}'[/tt]

Annihilannic.

 

[mrn]

cat file | awk -v FS=":" '{print $2":"$1}' > newfile

Mike

"A foolproof method for sculpting an elephant: first, get a huge block of marble, then you chip away everything that doesn't look like an elephant."

http://www.airport-parking-site.co.uk/

 

[PHV]

man cut
man uniq

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[SamBones]

Here's a Korn shell solution...

while IFS=: read USER UID; do print "${UID}:${USER}"; done < /input/file

To print the duplicate userids...

cut -d: -f2 /input/file | sort -n | uniq -d