I wrote following line in my script , but it not assigning any value to variable a

a= grep -n mark /etc/samba/smb.conf |cut -d: f1

I aspect line number where mark string present in smb.conf in variable a. But value of variable is null. What may be the issue


Two things:

  1. There can be no spaces between name of the variable, the = signal and the value of the variable
  2. If you want to put the results of a command or series of commands on a variable, you must enclose it on $(command) or old style backticks. Both lines below are correct and do the same thing:


So your line must be

a=$(grep -n mark /etc/samba/smb.conf |cut -d: f1)

There are some differences on how to concatenate the use of backticks or new style $(), check this question on SO to see a good response.

  • +1. I recommend putting the delimiter character in single quotes, too: -d':'. It's not needed here, but it's a good habit to have. – SmallClanger Mar 9 '11 at 13:06
a=`grep -n mark /etc/samba/smb.conf |cut -d: -f1`

Try this instead

a=$(grep -n mark /etc/samba/smb.conf |cut -d: f1)

Or instead of the $() you could use backticks (which here turn on the nice code look)


Should be a=$( ... ) or

a=` … `

Maybe by trying to use cut like this:

a=`grep -n mark /etc/samba/smb.conf |cut -d: -f1`

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.