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HELP | unix | regular expression - How to represent two whitespaces?

 
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# 1  
Old 10-12-2009
HELP | unix | regular expression - How to represent two whitespaces?
ls -l generates something like...

Code:
-rwxr-xr-x 1 root root   19304 Jan 21  2009 true
-rwsr-xr-x 1 root root   40208 Jan 21  2009 umount
-rwxr-xr-x 1 root root   22336 Jan 21  2009 uname
-rwxr-xr-x 1 root root    1273 Jan 21  2009 unicode_start
-rwxr-xr-x 1 root root      79 Jan 21  2009 unicode_stop
-rwxr-xr-x 1 root root   20576 Jan 21  2009 unlink
-rwxr-xr-x 1 root root   31280 Mar 11  2009 usleep
-rwxr-xr-x 1 root root  632816 Nov 25  2008 vi
lrwxrwxrwx 1 root root       2 Mar  4  2009 view -> vi
lrwxrwxrwx 1 root root       8 Mar  3  2009 ypdomainname -> hostname
-rwxr-xr-x 3 root root   62864 May 28  2008 zcat
-rwxr-xr-x 1 root root  594848 Jan  7  2007 zsh

I want to change each line so that each line has at most one whitespace between characters.

I think I can do this if I knew how to represent two whitespaces. It seems " " or ' ' has the same value as " " or ' '. The first set of quotes have one space and the second set of quotes has two spaces.

I want to be able to take any output that prints into columns and then use something like cut or grep to select futher manipulate the output to only the columns I want. Or something that would tokenize the string. I haven't used sed/awk, but I want to do it with grep, tr or cut preferably.
# 2  
Old 10-12-2009
Hi.

As for your first point:
Code:
ls -l | sed ":h;s/  / /;th"

Got a bit lost after that. What is the end result you want?
# 3  
Old 10-12-2009
Hey, thanks for the reply. sed is a pretty powerful tool.

I was able to do it with tr as well:

Code:
ls -l | tr -s ' '

Still wondering if its possible to do something similar with grep?
# 4  
Old 10-12-2009
You're right. tr works too. I'll remember that one (at least when I'm using Linux). Thanks.
 
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