Awk field seperator

[spex]

Hi,

Change awk's field separator regex to recognize both . and space.

$ echo hello1 192.168.1.9 | awk -F'[. ]' '{print $2"."$3"."$4}'
192.168.1

PCS

[Geoff Wild]

Very nice spex - definately a 10 in my books!

I would have just piped through 2 awk statements - forgot about regex.

IE:

echo hello1 192.168.1.9 | awk '{print $2}' | awk -F. '{print $1"."$2"."$3}'


Rgds...Geoff

[James R. Ferguson]

Hi (again):

Well, it appears that Spex and I agree on the solution :-))

Regards!

...JRF...

[Hein van den Heuvel · Accepted solution]

I would use a -F [ .] solution.
But you could take the default whitespace field seperator and substitute a period followed by numbers at the end of $2 with nothing:

awk '{sub (/.[0-9]+$/,"",$2); print $2}'

Or you can 'match' the first 3 groups of numbers seperated by a period and print that.
That would allow this to work in free formatted text, not just on 'the second field'.

awk '{match($0,/[0-9]+\.[0-9]+\.[0-9]+/); print substr($0,RSTART,RLENGTH)}'

Enjoy,
Hein.

[albanese]

I prefer James R. Ferguson Solution.. Cheers.

[maliaka]

Thanks a lot for the great solutions.

Have you guys tried to double quote the echo string?
By default the -F,FS and OFS are a space character so if you put the echo string in double quote, it preserves the white space and therefore mess it up if add spaces. Try it.

Hein has provided the best solution so far!!!

Open for debate.

[Peter Nikitka]

Hi,

the result of
echo a b | prog
echo 'a b' | prog
echo "a b" | prog

or
prog $(echo a b)
...

will be the same. In the view of the 'echo' command, it's different - in the first case it sees two parameters, in the other one parameter. But the result is the same: 'echo' will send the two parameters to its output, seperated by a space - which is exactly the same in case 2 or 3, where the space is taken from the original input of the single parameter.

Different will be a scenario like this:
echo ab
echo 'ab'

Only in the first case the result would NOT contain a TAB, but a space!

mfG Peter

[maliaka]

I have another question?

I would like to get only the first line from the output? (whatever the output might be).

awk '/'hell'/ && !/awk/ {print
$3}' /tmp/target.txt
HH
HH
HH
HH

[Denver Osborn]

to get the first line of the output, no matter what it may be... just pipe it to head -1.

awk '/'hell'/ && !/awk/ {print $2}' /tmp/target.txt |head -1

-denver

[Denver Osborn]

also w/ awk using your syntax modified...

awk 'NR>1{exit}/'hell'/ && !/awk/ {print $3}' /tmp/target.txt

-denver