stop_error Subroutine

  subroutine stop_error(msg)
    ! Aborts the program with nonzero exit code
    !
    ! The statement "stop msg" will return 0 exit code when compiled using
    ! gfortran.
    ! stop_error() uses the statement "stop 1" which returns an exit code
    ! 1 and a print statement to print the message.
    !
    ! Example
    ! -------
    ! call stop_error("Invalid argument")
    character(len=*) :: msg ! Message to print on stderr
    write(0,*) msg
    stop 1
  end subroutine stop_error