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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