[Tutor] Checking and showing all errors before of exit

[Jonas Melian]

Kent Johnson wrote:
> 
>>Is there any way of checking all possible errors, show you all error
>>messages, and then exit.
> 
> I don't understand your question. Can you give an example of what you would like to do?
> 
The idea was check all exceptions before of exit. I made it :)

flag_error = False
for x in [dir_lo, dir_k, dir_x]:
    try:
        os.listdir(x)
    except OSError, err_o:
        flag_error = True
        print "Error! %s: %r" % (err_o.strerror, err_o.filename)

if flag_error:
    sys.exit()

Now, I have a dudes:

1) Is it necessary use .exit() with some value (as 1) for indicate that
has been an error?

2) With .listdir() the exception can checks if the directory exist, but
how check if there are files in that directory too?

Thanks in advance!