Ok, cool.

grep -o prints just the matching sting on its own line.
[^ ]*$ matches any number of non-space, non-tab characters in a sequence that are at the of a line.

So, this seems good for grabbing text at the end of any line.

However, I'm still trying to match lines that can exactly n matches. MY current thoughts are find a line with only two 'x':

Code:

ls -aLl -R /bin | grep -o 'x.*x[^x]*'

x.*x[^x]* = find a 'x', followed by any number of any character, find a 'x', followed by any number of characters not 'x'
This just list highlights the entire line.

Code:

ls -aLl -R /bin | grep 'x'

This highlights each 'x' in a line without highlighting any other characters. Match any number of 'x'.

Code:

ls -aLl -R /bin | grep 'x\+'

This does the same as the above. Match any number of 'x'.

Code:

ls -aLl -R /bin | grep 'x\{n\}'

n = 1, matches like the above two examples. Match any number of 'x'.
n = 2, matches only when 'x' in a sequence of two. Sequence of four match because 'xxxx' is 'xx' 'xx', 'xxx' is only matched 'xx'. (I think).

Code:

ls -aLl -R /bin | grep 'x.*x'

This highlights all the characters between the first 'x' and last 'x'. Match at least two 'x'.

Code:

ls -aLl -R /bin | grep 'x.*x\{1\}'

This, appears to match the same sections in a line as the above code. Match at least two 'x'.

Code:

ls -aLl -R /bin | grep  '[^x]*'

This only highlights the line up until the first 'x'. Match all characters up until the first 'x'.

I think the issue may relate to the "greedy" regex engine, so to control it is the issue.
I think I may need to specify hard limit with \{1\}.
Also I'm not sure if I can use look ahead/behind/around or conidtional with grep's regular expressions, but these commands may solve the problem as well. x\(?!x\)
I may possibly need to use \? before the "." for cases that are xxx and I want to match exactly two 'x'.

Side question:
[^ ] == [^[:blank:]] == horizontal space, tab == \t
Horizontal single space == " " but it has no numerical representation for an amount like " " is the literal equivalent to " "?