[7m bin/osh Usage [0;0m

    Usage: osh [OPTION]... SCRIPT [ARG]...
           osh [OPTION]... -c COMMAND [ARG]...

The command line accepted by `bin/osh` is compatible with `/bin/sh` and `bash`.

    osh -c 'echo hi'
    osh myscript.sh
    echo 'echo hi' | osh

It also has a few enhancements:

    osh -n -c 'hello'                    # pretty-print the AST
    osh --ast-format text -n -c 'hello'  # print it full

osh accepts POSIX sh flags, with these additions:

  -n             parse the program but don't execute it.  Print the AST.
  --ast-format   what format the AST should be in
