Custom exit codes (exit N) in Bash Scripting - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the exit code of this script?

Consider this bash script:

#!/bin/bash
exit 42

What will be the exit code when this script finishes?

Bash Scripting

#!/bin/bash
exit 42

A 42

B 0

C 1

D 255

💡 Hint

The exit command returns the number you give it as the exit code.

The script uses 'exit 42', so the exit code is 42.

💻 Command Output

intermediate

What is the exit code after this command?

You run this command in bash:

exit 300

What will be the actual exit code returned?

Bash Scripting

exit 300

A 44

B 300

C 255

D 0

💡 Hint

Exit codes are limited to 0-255 and wrap around using modulo 256.

300 modulo 256 is 44, so the exit code is 44.

🔧 Debug

advanced

Why does this script always exit with code 0?

Look at this script:

#!/bin/bash
false
exit 0

Why does it always exit with code 0 even though 'false' failed?

Bash Scripting

#!/bin/bash
false
exit 0

A Because the shell ignores exit codes from commands.

B Because 'false' actually returns 0.

C Because exit codes are always 0 unless an error is caught.

D Because the script explicitly exits with 0, ignoring previous commands.

💡 Hint

The last exit command sets the script's exit code.

The script runs 'false' which returns 1, but then runs 'exit 0' which sets the exit code to 0.

🧠 Conceptual

advanced

What is the valid range for exit codes in bash?

Which of these is the correct range for exit codes in bash scripts?

A -128 to 127

B 0 to 1024

C 0 to 255

D Any integer value

💡 Hint

Exit codes are stored in a single byte.

Exit codes are 8-bit unsigned integers, so valid values are 0 to 255.

🚀 Application

expert

What is the exit code of this script?

Consider this bash script:

#!/bin/bash
if false; then
  exit 1
else
  exit 256
fi

What exit code will the script return when run?

Bash Scripting

#!/bin/bash
if false; then
  exit 1
else
  exit 256
fi

A 1

B 0

C 256

D 9

💡 Hint

256 modulo 256 is 0.

The 'if false' condition fails, so the else branch runs 'exit 256'. 256 modulo 256 is 0, so exit code is 0.