Option parsing with getopts in Bash Scripting - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to correctly initialize the option parsing loop using getopts.

Bash Scripting

while getopts [1] opt; do
  case $opt in
    h) echo "Help message"; exit 0;;
    *) echo "Invalid option"; exit 1;;
  esac
done

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

A"-h"

B"h"

C"a:b"

D"ab"

Attempts:

3 left

💡 Hint

Common Mistakes

Including a dash '-' in the option string.

Using multiple letters when only one is needed.

Adding a colon when the option does not take an argument.

The getopts string should contain the option letters to parse. Here, only 'h' is expected, so "h" is correct.

2fill in blank

medium

Complete the code to correctly check if the option requires an argument.

Bash Scripting

while getopts "f[1]" opt; do
  case $opt in
    f) filename=$OPTARG;;
    *) echo "Unknown option"; exit 1;;
  esac
done

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

A:

Bf

Cg

Dh

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting the colon after the option letter that requires an argument.

Adding letters without colons for options that need arguments.

A colon ':' after an option letter means that option requires an argument. Here, 'f:' means option 'f' needs an argument.

3fill in blank

hard

Fix the error in the option parsing loop to correctly handle unknown options.

Bash Scripting

while getopts "ab" [1]; do
  case $opt in
    a) echo "Option a";;
    b) echo "Option b";;
    *) echo "Unknown option: $opt"; exit 1;;
  esac
done

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

Aarg

Boptarg

Coption

Dopt

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different variable name after getopts than in the case statement.

Using $OPTARG instead of the option variable for case matching.

The variable after getopts is the option variable name. It must match the variable used in the case statement. Here, 'opt' is correct.

4fill in blank

hard

Fill both blanks to correctly parse options 'u' with argument and 'v' without argument.

Bash Scripting

while getopts [1] [2]; do
  case $opt in
    u) user=$OPTARG;;
    v) verbose=1;;
    *) echo "Invalid option"; exit 1;;
  esac
done

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

A"u:v"

B"uv"

Copt

Doptarg

Attempts:

3 left

💡 Hint

Common Mistakes

Not adding a colon after 'u' if it requires an argument.

Using a variable name different from 'opt' in the loop.

The option string "u:v" means 'u' and 'v' are options; 'u' requires an argument due to the colon after u, while 'v' does not. The variable after getopts is 'opt' as used in the case.

5fill in blank

hard

Fill all three blanks to create a dictionary of options and their arguments, skipping options without arguments.

Bash Scripting

declare -A opts
while getopts [1] [2]; do
  case $opt in
    u) opts[[3]]=$OPTARG;;
    v) opts[verbose]=1;;
    *) echo "Unknown option"; exit 1;;
  esac
done

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

A"u:v"

Bopt

C"user"

D"opt"

Attempts:

3 left

💡 Hint

Common Mistakes

Not using quotes around the dictionary key.

Using the wrong variable name after getopts.

Missing colon after option letter that requires argument.

The option string "u:v" means 'u' requires an argument, 'v' does not. The variable after getopts is 'opt'. The key for the dictionary is 'user' as a string.