while read loop preserving leading whitespace - Shell Programming and Scripting

zazzybob · #1 (**permalink**) 06-07-2004

Hi all,

I've been trying to get this to work for ages to no avail. I've searched this site and googled but cannot find a satisfactory answer.

I've got a while loop, like this

Code:

while read line
do
    echo "$line"
done < file_name

Now, my problem is that most of the lines in the file have indentation (this program parses indented source code).

The indentation is lost during the loop and everything appears left-justified.

Now, am I missing something *really* silly here?

Peace,
ZB

Ygor · #2 (**permalink**) 06-07-2004

Just change the value of IFS, e.g....

Code:

( IFS='\n' 
  while read line
  do
      echo "$line"
  done < file_name )

zazzybob · #3 (**permalink**) 06-07-2004

Many thanks Ygor, I thought it'd be something fairly simple!

Cheers
ZB

zazzybob · #4 (**permalink**) 06-07-2004

Just thought I'd let everyone know that I decided to implement this in awk in the end, as processing the syntax of a gazillion shell scripts is easier to do with awk. As $0 can just be processed the way I wanted leaving whitespace intact using "\n" as the RS.

I am writing a script which will convert shell syntax to colour-highlighted HTML. I found scripts to do this for just about every language EXCEPT for humble old SH so I decided to do it myself! You can view a sample output from the script HERE . The script itself is still under test and thus is not yet online.

Sorry for the "shameless plug" but I thought I'd let everybody know what the purpose of my original post was.

Peace
ZB

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