topic Re: Awk Variable Substition in Operating System - Linux

Awk Variable Substition

gstonian — Mon, 11 Dec 2006 09:30:32 GMT

Hey,

Just want to strip everything prior to the last backslash for a paramter in a file using awk.

i.e.

cat file | awk ' BEGIN { FS="\n" ; RS="" } { print $5 } '
Test\SQL Servers\Server1
Edinburgh\SQL Servers\Server2
London\SQL Servers\Server3
Test Servers\Server4

to be
Server1
Server2
Server3

Outside of awk I know i can do ${variable##*\\}
but not sure how to get it to work alongside awk and everything I see appears to work on the first occurence i.e.

awk ' BEGIN { FS="\n" ; RS="" } { print substr($5,(index($5, "\\")+1),20) } '
works on the first occurence of "\" but doesn't handle any further occurences

I'm sure I'm missing something simple here so please let me know ;-)

Cheers

Re: Awk Variable Substition

john korterman — Mon, 11 Dec 2006 09:47:59 GMT

Hi,

you just want the last part?

awk -F\\ '{print $NF }' infile

regards,
John K.

Re: Awk Variable Substition

James R. Ferguson — Mon, 11 Dec 2006 09:48:04 GMT

Hi:

In Perl, dimply:

# perl -nle 'print $1 if m/.*\\(.*)/' filename

Regards!

...JRF...

Re: Awk Variable Substition

gstonian — Mon, 11 Dec 2006 09:52:07 GMT

Thanks but it's not the last part of the file, just simply the last part of the parameter ($5) I want to print. There are other fields after this one $6,$7 etc. I just simplified the issue down .

Thanks for the perl solution but would like to use awk if possible

Cheers

Re: Awk Variable Substition

James R. Ferguson — Mon, 11 Dec 2006 10:06:38 GMT

Hi (again):

OK, then in 'awk':

# awk '{sub(/.+\\/, "",$0);print}' filename

Regards!

...JRF...

Re: Awk Variable Substition

Tom Danzig — Mon, 11 Dec 2006 10:45:19 GMT

Sounds like basename would be the simplest in your situation:

# basename London\SQL Servers\Server3
LondonSQL

Easiest awk would be:
awk -F'\' '{print $NF}' filename

Re: Awk Variable Substition

Tom Danzig — Mon, 11 Dec 2006 10:52:32 GMT

Please excuse my ridiculous 'basename' suggestion above.

Re: Awk Variable Substition

gstonian — Mon, 11 Dec 2006 10:56:58 GMT

NO problem,

I am trying to do something with other parameters and formatting the input so ideally would like something to be able to do something all in one line

i.e.

| awk ' BEGIN { FS="\n" ; RS="" } { print $1 ", " $2 ", " $3 ", " ", " $6 } '

Re: Awk Variable Substition

Peter Nikitka — Mon, 11 Dec 2006 11:47:33 GMT

Hi,

just split the filed in request using '\' as seperator:

awk 'BEGIN { FS="\n" ; RS="" }
{n=split($5,a,"\\"); if(n>1) print a[n]}' file

mfG Peter

Re: Awk Variable Substition

Peter Nikitka — Mon, 11 Dec 2006 12:01:41 GMT

Hi,

sorry for the follow-up, but I missed your last post.

To include my solution into in your code, use
the splitted result directly. If you set ORS, then there is no need to diddle with output formatting:

| awk ' BEGIN { FS="\n" ; RS=""; ORS=" " }
{ n=split($5,a,"\\"); print $1,$2,$3,a[5],$6}'

mfG Peter

Re: Awk Variable Substition

gstonian — Tue, 12 Dec 2006 04:27:35 GMT

Thanks for all your answers. I ended up taking your answers and ended up with using awk twice to get what I wanted, which was.

cat file.out | awk -F\\ '{print $NF } ' | awk ' BEGIN { FS="\n" ; RS="" } { print $1", "$2", "$3", "$4", "$5" "$7" "$8} '

Hope someone else finds a use for this !

Re: Awk Variable Substition

gstonian — Tue, 12 Dec 2006 04:29:02 GMT

Thanks