You cannot submit for this problem because the homework's deadline is due.

Final Pretest

Memory leaks and undefined behaviors are tested here but not counted into grade.

Hint: LeakSanitizer is unstable. You may ignore the cases when it meets fatal error.

Tasks

12. Handle errors for all supported features. [10]

• Case: 1-8
• At most one of these error occurs in a command
• Non-existing program (Case 1)
  • input: non-exist abc def
  • input: echo abc | non-exist
  • output: non-exist: command not found
• Non-existing file in input redirection (Case 2)
  • input: cat < non-existing.txt
  • output: non-existing.txt: No such file or directory
• Failed to open file in output redirection (Case 3)
  • input: echo abc > /dev/permission_denied
  • output: /dev/permission_denied: Permission denied
• Duplicated input redirection (Case 4)
  • input: echo abc < 1.txt < 2.txt
  • input: echo abc | grep abc < 1.txt
  • output: error: duplicated input redirection
• Duplicated output redirection (Case 5)
  • input: echo abc > 1.txt > 2.txt
  • input: echo abc > 1.txt >> 2.txt
  • input: echo abc > 1.txt | grep abc
  • output: error: duplicated output redirection
• Syntax Error (Case 6)
  • input: echo abc > > > >
  • output: syntax error near unexpected token `>'
  • input: echo abc > < 1.txt
  • output: syntax error near unexpected token `<'
  • input: echo abc > | grep abc
  • output: syntax error near unexpected token `|'
• Missing program (Case 7)
  • input: > abc | | grep 123
  • output: error: missing program
• cd to non-existing directory (Case 8)
  • input: cd non-existing
  • output: non-existing: No such file or directory