CODEWITHSUNDEEP
unix
Jackie James
Jackie James

Reputation: 853

How to store the value of cat command in the variable var?

I'm trying to find the number of times a string is repeated in a file, at the same time i've to store it in a variable.

When i use the command (cat filename | grep -c '123456789') , it displays the count correctly but when i use the below command it shows as command not found.

var =$(cat filename | grep -c '123456789')
echo $var

Can u let me know where i'm wrong ?

Upvotes: 8

Views: 43224

Answers (3)

Basile Starynkevitch
Basile Starynkevitch

Reputation: 1

Don't use spaces around the = sign:

var=$(cat filename | grep -c '123456789')

Read at least the Bash Prog Intro Howto

But you've got a useless use of cat so code simply

    var=$(grep -c '123456789' filename)

Upvotes: 16

ghoti
ghoti

Reputation: 46826

Remember that grep can read the file directly. You can avoid useless use of cat.

In the example in your question, the command not found error occurs because of the space before the equals sign. Try this instead:

var=$(grep -c '123456789' filename)

or if you're using bash:

read var < <(grep -c '123456789' filename)

or (for completeness) in csh/tcsh:

setenv var `grep -c '123456789' filename`

Upvotes: 5

Levon
Levon

Reputation: 143047

Using backquotes will also work:

varx=`( cat filename| grep -c '123456789' )`

I.e., the $ is not required, you can assign the output of various commands to variables through the use of backquotes.

For instance:

$ pwd
/home/user99

$ cur_dir=`pwd`
$ echo $cur_dir
/home/user99

Upvotes: 1

Related Questions