Lesson 9

Date: 3/26/2014
Linux shell scripting tutorial
Linux for Engineering and IT Applications


Using quotes

  • Single forward quotes ' protect the enclosed text from the shell. 
    echo 'error $?'
echo 'shell name $0'

  • Double quotes allow all shell interpretations to take place inside them. 
    echo "error $?" #gives the error code of the last command 
echo "shell name $0" #gives the current shell name

  • Command substitution 
    X=`expr 100 + 50 '*' 3`
echo $X


    FSIZE=`wc -l /etc/profile`
    same as 
    FSIZE=$(wc -l /etc/profile)


    • Take me to the Course Website