shell script basic doubt

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# 1  
Old 09-10-2009
Bug shell script basic doubt

I am new script learner,
so my basic doubt is ,
how to store value of any command in a variable example
$ ls | wc -l

i want to stote the output of this in a variable c.
so that i can use c in if else loop.

and when do we use " ` " symbol in script..
can anyone also tell for learner whick ebook i should use..
# 2  
Old 09-10-2009
to put command in variable....

var=$(ls | wc -l);echo $var

# 3  
Old 09-10-2009
You can assign the output of a command to a variable as follow:

c=`ls | wc -l`


c=$(ls | wc -l)

Some useful links:
# 4  
Old 09-10-2009
Thanks for reply,
can you please help me , i am trying to write just small script, for testing, i am getting error as follows..

var=$(ls | wc -l)
echo $var
if [$var -eq 3]
                echo "its true"
                echo "its false"


$ ./script
./script: line 8: [3: command not found
# 5  
Old 09-10-2009
Give a space after "[".

if [ $var -eq 3 ]

# 6  
Old 09-10-2009
Thanks protocomm, Franklin52, panyam

I am able to learn script with u all guys,
now my test script is running.
Thanks alot.
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