Shell Programming and Scripting

If you really want to use cat:

Code:

cat file | while read line 
do
echo "$line"
if [ -z "${line}" ]; then 
 echo "Blank line"
fi
done

cheers,
Devaraj Takhellambam

Further to abubacker and for completeness.
We put $groupline in double quotes or we get a syntax error from the if statement if the line is blank.
As other posters note the "for" method loses the blank line completely when expanding the output from "cat" on the command line.
The "while read" construct is preferred because it can deal with any number of records whereas the "for" method could expand to a command line which fails because it is too long.

A version with "cat":

Code:

cat /home/test/group | while read groupline
do
         if [ -z "${groupline}" ]
             then
             echo "blank found"
         fi 
done

if you can insert a -n into the cat statement you can work out from the line numbers if a line is blank.

What about this?

Code:

cat myfile | od -An -t dC -w10

Which will provide the decimal ASCII representation of what is on a line.

Does that help you?

Dear Friend,

If you want to print the file content with the empty line, you can use the -A option with cat command.

I have written the following code. It is print the empty line also. But it will print the empty line as $.

The file content is
welcome

welcome 1

welcome 2

Code:

 
for line in `cat -A 1`
do
        echo $line;
done

The output is
welcome$
$
welcome1$
$
welcome2$