Question

I am getting an error when I try and run my assignment.

#!/bin/bash
## Assignment 2

echo Please enter a User Name:
read u
if [ $u!="root"]; then
        echo Searching for Username!
        grep $u /etc/passwd|sed 's/$u/hidden/gi'
elif [ $u!="toor"]; then
        echo Root is NOT allowed.
else
        echo Toor is definetely NOT allowed.
fi

Output:

Please enter a User Name:
user1
./assign2.sh: line 6: [bthiessen: command not found
./assign2.sh: line 9: [bthiessen: command not found
Toor is definetely NOT allowed.

What is wrong with my if statements?

Answer 1

Try that :

#!/bin/bash

echo Please enter a User Name:
read u
if [[ $u != "root" ]]; then
        echo Searching for Username!
        grep "$u" /etc/passwd | sed "s/$u/hidden/gi"
elif [[ $u != "toor" ]]; then
        echo Root is NOT allowed.
else
        echo Toor is definetely NOT allowed.
fi

problems founds :

• [ $u!="root"] need spaces around !=
• if you use variables in sed, you need " quotes, not simple '

note :

[[ is a bash keyword similar to (but more powerful than) the [ command. See http://mywiki.wooledge.org/BashFAQ/031 and http://mywiki.wooledge.org/BashGuide/TestsAndConditionals . Unless you’re writing for POSIX sh, we recommend [[

Learn the difference between ' and " and `. See http://mywiki.wooledge.org/Quotes and http://wiki.bash-hackers.org/syntax/words