URGENT!!!! Anyone knows how to programme in linux?

grail · 12-02-2014, 09:14 PM

Ok ... it seems we jumped the gun.

Try reading something like http://tldp.org/LDP/abs/html/

Specifically look for #,## and %,%% and also ${#variable_name}:

Code:

var='one two three four'

f_pos="${var%f*}f"

len=${#f_pos}

echo $len

This would show you which position the letter 'f' is at in the original string

jeffrey1289 · 12-02-2014, 09:28 PM

I don't have a textbook....

grail · 12-02-2014, 10:24 PM

So you are doing a course and there is no textbook, course notes or online material provided ... how very strange. In this case I would probably suggest changing to a course / school where it is reputable and actually
provides the material required for learning.

rknichols · 12-03-2014, 04:02 PM

I agree it doesn't seem like a very well organized course, and your code samples to date seem to indicate that you've just jumped into the deep end of the pool, e.g.:

Quote:

Originally Posted by jeffrey1289

Code:

 
    if length "$line" | grep '^[^;]' > max
      max=length "$line" | grep '^[^;]'

That is so far removed from any syntax I know that I can't even tell what language it's supposed to be.

Just some useful hints:

Code:

Matcher="^([^;].*[^ ]) *(;.*)"     # A regular expression to match a string beginning with something other
                                   #   than a semicolon, followed by a string of any characters up through
                                   #   the last non-space character that is then followed by any spaces and
                                   #   a semicolon then followed by any number of characters.  (Whew!)
if [[ $Line =~ $Matcher ]]; then   # If line contains both code and comment
    Code="${BASH_REMATCH[1]}"      # First parenthesized segment is just the code w/o trailing spaces
    Comment="${BASH_REMATCH[2]}"   # Second parenthesized segment is the comment
    Code_length=${#Code}           # Length of $Code
    .
    .
    .
fi