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Full Discussion: Reading a file line by line and processing for each line
Top Forums Shell Programming and Scripting Reading a file line by line and processing for each line Post 302292411 by cfajohnson on Friday 27th of February 2009 07:39:09 PM
Old 02-27-2009
Quote:
Originally Posted by adderek
Beginner? This is one of the better ksh codes that I have seen. And believe me - I have seen plenty od it.

You must be joking! It's extremely inefficient and poorly written code.
Quote:
Some hints that might help you:
- Try enclosing variables with quotes: variable="${var}" (the way you are using could work fine but under some circumstances you can get into problems - an example is when ${var} is equal to 'some text with $trange characters').

It is never necessary to quote the assignment of one variable to another; it doesn't matter what the variable contains. It only needs to be quoted when there is a literal space in the assignment:

Code:
x='the quick brown fox' ## Quotes necessary for literal spaces
var=$x  ## No quotes necessary

Quote:
- I'm not sure if there is a need to enclose that function within brackets - if I remember correct you should be able to "print" the file into the loop without brackets

There's no need, but it doesn't hurt.
Quote:
- Send this sid_home.txt file and make sure that the problem is not related to end of line characters (unix/max/windows format) - if you send it then I could take a look onto it

Why? All that's needed is to look at the file with od -c and look for \r characters.

However, it would help to post a few lines of the file so we can see what the input to the loop contains.

It should contain a list of filenames, since $LINE is being used as a filename argument to the (probably unnecessary) awk commands.
Quote:
- Use tabulation - this code you have sent is not very readable

I think you mean indentation. That's always good, and more importantly, code posted to this forum should always be enclosed in [code] tags.
Quote:
- You might try the alternative syntax as well (might be worth giving a try): cat "${file}" |

Why would you use cat? It cannot make any difference.
Quote:
while $(read LINE);do ... done

What do you think while $(read LINE) does?

The assignment to LINE only lasts for the duration of the subshell inside $( ... ); it will not be available to the rest of the script.

In other words, it does nothing.
Quote:
- Execute your code with "set -x;set -v" and check the output. You might try some debuggers as well.
 

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