Bash - Check your knowledge

Every order must return a return code at the end of its execution:

• True
• False

A return code of 0 indicates an execution error:

• True
• False

The return code is stored in the variable $@:

• True
• False

The test command allows you to:

• Test the type of a file
• Test a variable
• Compare numbers
• Compare the content of 2 files

The command expr:

• Concatenates 2 strings of characters
• Performs mathematical operations
• Display text on the screen

Does the syntax of the conditional structure below seem correct to you? Explain why.

if command
    command if $?=0
else
    command if $?!=0
fi

• True
• False

What does the following syntax mean: ${variable:=value}

• Displays a replacement value if the variable is empty
• Display a replacement value if the variable is not empty
• Assigns a new value to the variable if it is empty

Does the syntax of the conditional alternative structure below seem correct to you? Explain why.

case $variable in
  value1)
    commands if $variable = value1
  value2)
    commands if $variable = value2
  *)
    commands for all values of $variable != of value1 and value2
    ;;
esac

• True
• False

Which of the following is not a structure for looping?

• while
• until
• loop
• for

Author: Antoine Le Morvan

Contributors: Steven Spencer, Ganna Zhyrnova