Help to write bash script code

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# 1  
Old 06-06-2011
Help to write bash script code

I am newbie to UNIX. I came across this exercise in one the books.Can anyone help me with this question??????

Write a short Bash script that, given the name of a file as an argument,
reads the file name and creates a new file containing only lines which consist
of one word. Here is an example
This is a special text file
are 20 students in the class.
[TAB][SPACE] Nearly
half of them are enrolled in FoS. The rest are in
The output from the script should look like
[TAB][SPACE] Nearly

Your help is much appreciated.
# 2  
Old 06-06-2011
hmmm.. assignment Smilie

so far, what you tried ??
# 3  
Old 06-06-2011
When you call your script with a filename -or something else- as an argument, you retrieve the first argument with "$1", the second with "$2", ...

echo "$1"

exit 0

This simple script above will give:
~$ ./this-simple-script "/path/to/file"

To read the file in '$1", you can simply cat "$1" but for the next requirement, write something with a loop that says:

while read the_line; do
	echo "$the_line"
done < "$1"

exit 0

From the example you wrote, you need to read every other line

while read the_line; do
	((i++%2)) && { echo "$the_line";}
done < "$1"

exit 0

i is a variable that's incremented (i++) on every line read.
i%2 returns 1 or 0, depending i is odd or even, basically, it returns 0 when i is 2; 4; 6; ...
And in sh/bash and many others scripting languages; zero means no errors.
No Errors: execute what's after the &&, so echo "$the_line"

Long talk, heh? Smilie

Last edited by tukuyomi; 06-06-2011 at 08:05 AM..
# 4  
Old 06-06-2011
try this
for line in `cat filename`; do
        if [[ $(echo $line | wc -w) -eq 1 ]]; then
                echo $line

# 5  
Old 06-06-2011
Thanks a lot to everyone!!!!!!!!!!!!
I will try the code and let you know...
Thanks again.

---------- Post updated at 05:19 AM ---------- Previous update was at 05:18 AM ----------

Hi Mr.itkamaraj,
This is not an assignment question. I am not studying at the moment. I am working as Support Engineer and learning bash scripting. I came across this question in some book and did not know the answer.

Last edited by krthknaidu; 06-06-2011 at 08:25 AM..
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