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AWK to print field $2 first, then field $1

Tags:

unix

awk

Here is the input(sample):

[email protected]|com.emailclient.account
[email protected]|com.socialsite.auth.account

I'm trying to achieve this:

Emailclient [email protected]
Socialsite [email protected]

If I use AWK like this:

cat foo | awk 'BEGIN{FS="|"} {print $2 " " $1}'

it messes up the output by overlaying field 1 on the top of field 2.

Any tips/suggestions? Thank you.

like image 759
Sazzy Avatar asked Mar 24 '13 11:03

Sazzy


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3 Answers

A couple of general tips (besides the DOS line ending issue):

cat is for concatenating files, it's not the only tool that can read files! If a command doesn't read files then use redirection like command < file.

You can set the field separator with the -F option so instead of:

cat foo | awk 'BEGIN{FS="|"} {print $2 " " $1}' 

Try:

awk -F'|' '{print $2" "$1}' foo 

This will output:

com.emailclient.account [email protected]
com.socialsite.auth.accoun [email protected]

To get the desired output you could do a variety of things. I'd probably split() the second field:

awk -F'|' '{split($2,a,".");print a[2]" "$1}' file
emailclient [email protected]
socialsite [email protected]

Finally to get the first character converted to uppercase is a bit of a pain in awk as you don't have a nice built in ucfirst() function:

awk -F'|' '{split($2,a,".");print toupper(substr(a[2],1,1)) substr(a[2],2),$1}' file
Emailclient [email protected]
Socialsite [email protected]

If you want something more concise (although you give up a sub-process) you could do:

awk -F'|' '{split($2,a,".");print a[2]" "$1}' file | sed 's/^./\U&/'
Emailclient [email protected]
Socialsite [email protected]
like image 174
Chris Seymour Avatar answered Oct 20 '22 15:10

Chris Seymour


Use a dot or a pipe as the field separator:

awk -v FS='[.|]' '{
    printf "%s%s %s.%s\n", toupper(substr($4,1,1)), substr($4,2), $1, $2
}' << END
[email protected]|com.emailclient.account
[email protected]|com.socialsite.auth.account
END

gives:

Emailclient [email protected]
Socialsite [email protected]
like image 3
glenn jackman Avatar answered Oct 20 '22 16:10

glenn jackman


Maybe your file contains CRLF terminator. Every lines followed by \r\n.

awk recognizes the $2 actually $2\r. The \r means goto the start of the line.

{print $2\r$1} will print $2 first, then return to the head, then print $1. So the field 2 is overlaid by the field 1.

like image 3
SleepyProgrammer Avatar answered Oct 20 '22 16:10

SleepyProgrammer