topic Re: commands in Operating System - Linux

commands

Shivkumar — Mon, 13 Nov 2006 20:19:12 GMT

Hi,

From the below word

:[rosePink]

i want to remove : [, and ]

i just want to extract rosePink.

How do i do that ?

Thanks,
Shiv

Re: commands

Rajeev Shukla — Mon, 13 Nov 2006 20:30:22 GMT

If you have that word in a file say "aa" then do this
sed -e 's/:\[//' -e 's/\]//' aa

Re: commands

James R. Ferguson — Mon, 13 Nov 2006 21:09:33 GMT

Hi Shiv:

Another way:

# echo "I am :[rosePink] I am" | perl -ne 'print $1 if m%.*\[(.+)\].*%'

# perl -ne 'print $1 if m%.*\[(.+)\].*%' file

Regards!

...JRF...

Re: commands

Shivkumar — Mon, 13 Nov 2006 21:19:03 GMT

we don't want to use the word "i am and also don't want to use perl"..

is there any other alternative using greg/egrep or awk ?

best regards,
shiv

Re: commands

Patrick Wallek — Mon, 13 Nov 2006 21:27:34 GMT

A solution using awk:

echo ":[rosePink]" | awk -F [ '{print $2}' | awk -F ] '{print $1}'

Re: commands

James R. Ferguson — Mon, 13 Nov 2006 21:49:15 GMT

Hi (again) Shiv:

You wrote, "we don't want to use the word "i am and also don't want to use perl".

First, the example I showed simply extracts the string contained in square brackets --- which was exactly the extent of what you asked.

Second, you never indicated what tools you would accept and what tools you would not. Perl was my choice.

# echo ":[rosePink]"|perl -nle 'print $1 if m%\[(.+)\]%'

Regards!

...JRF...

Re: commands

Hein van den Heuvel — Mon, 13 Nov 2006 22:23:12 GMT

$ echo :[rosePink] | awk -F [\]\[] '{ print $2}'
rosePink

Actually, as much as I often think Shiv shoudl use study the man pages a bit more, and just try some stuff to learn, this time he is onto something tricky.

The square brackets are tricky to specify as they are a critical part of regular expression.

As we all know, awk can use a regulare expression as field seperator. And boxed characters are a choicelist of sort. Pick "i" and "o" as seperators and this works...

$ echo :[rosePink] | awk -F [io] '{ print $2}'
seP

Now pick "[" and "]"... no go...
$ echo :[rosePink] | awk -F [[]] '{ print $2}'

Ok, so escape them.... no go...

$ echo :[rosePink] | awk -F [\[\]] '{ print $2}'

Now escape them, and re-order and it works:

$ echo :[rosePink] | awk -F [\]\[] '{ print $2}'
rosePink

At first I though i was battling the shell on top of awk, but even using a tiny awk program you need to take thenm out of order.

$ cat test.awk
BEGIN { FS="[][]" }
{ print "1=" $1 " 2=" $2 " 3=" $3 }
$ echo :[test]aaa | awk -f x.awk
1=: 2=test 3=aaa

grins,
Hein.

Re: commands

Hein van den Heuvel — Mon, 13 Nov 2006 22:51:27 GMT

Hmm,

Shiv wrote> i want to remove : [, and ]

taking that original request literally the solution would be:

$ echo :[rosePink] | tr -d :[]
rosePink

Or with symbols:

$ x=:[rosePink]
$ y=$(echo $x | tr -d :[])
$ echo $x " - " $y
:[rosePink] - rosePink

Hein.

Re: commands

Shivkumar — Tue, 14 Nov 2006 00:45:10 GMT

Thanks James!!

I respect your choice of tools as always.

Best Regards,
Shiv

Re: commands

Arturo Galbiati — Wed, 15 Nov 2006 05:53:10 GMT

Hi Shiv
this run fine on my Hp-UX11i:
% echo ":[rosePink]"|tr -d [:punct:]
rosePink

HTH,
Art

Re: commands

Dennis Handly — Wed, 15 Nov 2006 06:09:47 GMT

>Arturo: tr -d [:punct:]

Yes, this will work, provided Shivkumar wants to remove ALL punctuation. White space is left.

Re: commands

Eric Raeburn — Fri, 01 Dec 2006 05:16:18 GMT

I believe this will provide a concise solution, without forceably removing all punctuation:

$ echo :[rosePink] | sed 's/:\[$.*$\]/\1/'
rosePink