Running scripts in Bash Scripting - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to run a script named myscript.sh in the current directory.

Bash Scripting

./[1]

Drag options to blanks, or click blank then click option'

Astart.sh

Bmyscript.sh

Cscript.sh

Drun.sh

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to use ./ before the script name.

Using the wrong script file name.

To run a script in the current directory, prefix the script name with ./ followed by the script file name.

2fill in blank

medium

Complete the command to make the script myscript.sh executable.

Bash Scripting

chmod [1] myscript.sh

Drag options to blanks, or click blank then click option'

A+x

Brwx

C-x

D777

Attempts:

3 left

💡 Hint

Common Mistakes

Using chmod rwx which sets permissions but not correctly.

Using chmod -x which removes execute permission.

The command chmod +x filename adds execute permission to the file.

3fill in blank

hard

Fix the error in the command to run myscript.sh with bash explicitly.

Bash Scripting

bash [1]

Drag options to blanks, or click blank then click option'

A./myscript

Bmyscript

C./myscript.sh

Dmyscript.sh

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting ./ causing 'file not found' error.

Using script name without extension.

To run a script with bash explicitly, provide the relative or absolute path including ./ if in current directory.

4fill in blank

hard

Fill both blanks to create a script that prints 'Hello' and then exits with status 0.

Bash Scripting

#!/bin/bash
 echo [1]
 exit [2]

Drag options to blanks, or click blank then click option'

A"Hello"

B0

C1

D'Hello'

Attempts:

3 left

💡 Hint

Common Mistakes

Not quoting the string, causing errors.

Using exit status other than 0 for success.

Use quotes around the string to print it correctly. Exit status 0 means success.

5fill in blank

hard

Fill all three blanks to create a script that takes one argument and prints it.

Bash Scripting

#!/bin/bash
 input=[1]
 echo [2]
 exit [3]

Drag options to blanks, or click blank then click option'

A$1

B$input

C0

D$0

Attempts:

3 left

💡 Hint

Common Mistakes

Using $0 which is the script name, not the argument.

Not exiting with 0 to indicate success.

Use $1 to get the first argument, print the variable, and exit with 0 for success.

Practice

1. What is the correct way to run a bash script named myscript.sh after making it executable?

easy

A. Use ./myscript.sh to run the script.

B. Use run myscript.sh to run the script.

C. Use execute myscript.sh to run the script.

D. Use start myscript.sh to run the script.

Solution

1. Step 1: Understand script execution permission

   Before running a script with ./myscript.sh, it must have execute permission set using chmod +x myscript.sh.

2. Step 2: Run the script using relative path

   Using ./myscript.sh runs the script in the current directory. Other commands like run, execute, or start are not valid bash commands.

3. Final Answer:

   Use ./myscript.sh to run the script. -> Option A

4. Quick Check:

   Executable script run with ./script.sh = A [OK]

Hint: Make script executable, then run with ./script.sh [OK]

Common Mistakes:

• Trying to run script without execute permission
• Using invalid commands like run or start
• Not specifying path to script

2. Which of the following is the correct syntax to run a bash script named backup.sh without changing its permissions?

easy

A. ./backup.sh

B. sh run backup.sh

C. bash backup.sh

D. execute backup.sh

Solution

1. Step 1: Understand running scripts without execute permission

   If the script is not executable, you can run it by explicitly calling the shell interpreter like bash backup.sh.

2. Step 2: Identify correct syntax

   bash backup.sh runs the script using bash without needing execute permission. Other options either require execute permission or are invalid commands.

3. Final Answer:

   bash backup.sh -> Option C

4. Quick Check:

   Run script with interpreter command = B [OK]

Hint: Use bash script.sh to run without execute permission [OK]

Common Mistakes:

• Trying to run with ./ without execute permission
• Using invalid commands like execute
• Adding extra words like 'run' before script name

3. Given the script hello.sh with content:

#!/bin/bash
echo "Hello, $1!"

What is the output of ./hello.sh World?

medium

A. Hello, $1!

B. Hello, World!

C. Hello, !

D. Syntax error

Solution

1. Step 1: Understand script parameter usage

   The script uses $1 which is the first argument passed to the script. Here, World is passed as the first argument.

2. Step 2: Predict output after substitution

   The echo command prints "Hello, World!" by replacing $1 with the argument.

3. Final Answer:

   Hello, World! -> Option B

4. Quick Check:

   Argument $1 replaced by 'World' = A [OK]

Hint: Arguments like $1 print passed values in scripts [OK]

Common Mistakes:

• Printing literal $1 instead of argument
• Missing argument causing empty output
• Assuming syntax error due to shebang

4. You try to run a script with ./myscript.sh but get Permission denied. What is the most likely fix?

medium

A. Add execute permission with chmod +x myscript.sh.

B. Run the script with ./myscript.sh again.

C. Rename the script to myscript.sh.sh.

D. Delete the script and create a new one.

Solution

1. Step 1: Identify cause of 'Permission denied'

   This error usually means the script file does not have execute permission.

2. Step 2: Fix permission issue

   Use chmod +x myscript.sh to add execute permission, allowing the script to run.

3. Final Answer:

   Add execute permission with chmod +x myscript.sh. -> Option A

4. Quick Check:

   Permission denied fixed by chmod +x = D [OK]

Hint: Use chmod +x to fix permission denied errors [OK]

Common Mistakes:

• Trying to run script again without changing permissions
• Renaming script does not fix permissions
• Deleting script is unnecessary

5. You want to run a script deploy.sh located in /home/user/scripts from anywhere in the terminal without typing the full path. What is the best way to do this?

hard

A. Run the script with bash /home/user/scripts/deploy.sh every time.

B. Copy deploy.sh to /tmp directory.

C. Rename the script to deploy without extension.

D. Add /home/user/scripts to the PATH environment variable.

Solution

1. Step 1: Understand PATH environment variable

   PATH lists directories where the shell looks for commands. Adding a directory lets you run scripts inside it by name.

2. Step 2: Add script directory to PATH

   By adding /home/user/scripts to PATH, you can run deploy.sh from anywhere simply by typing deploy.sh.

3. Final Answer:

   Add /home/user/scripts to the PATH environment variable. -> Option D

4. Quick Check:

   PATH addition enables running scripts anywhere = C [OK]

Hint: Add script folder to PATH to run scripts anywhere [OK]

Common Mistakes:

• Copying script to /tmp is temporary and not recommended
• Running with full path every time is inconvenient
• Renaming script does not affect running from anywhere