Steve Nelson wrote: > On 9/22/06, Steve Nelson <[EMAIL PROTECTED]> wrote: > >> In the end I just did: >> >> def fsUsage(dir): >> """Returns the % usage of a given filesystem""" >> stat = os.statvfs(dir) >> from statvfs import F_BLOCKS, F_BFREE >> total = stat[F_BLOCKS] >> avail = stat[F_BFREE] >> used = total-avail >> percent = used/total*100 >> return percent > > Can someone explain how I manged to import F_BLOCKS and F_BFREE?
With the statement from statvfs import F_BLOCKS, F_BFREE > > I want to do the same with pwd and grp: > >>>> gstat = grp.getgrgid(1) >>>> dir(gstat) > ['__add__', '__class__', '__contains__', '__delattr__', '__doc__', > '__eq__', '__ge__', '__getattribute__', '__getitem__', '__getslice__', > '__gt__', '__hash__', '__init__', '__le__', '__len__', '__lt__', > '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', > '__repr__', '__rmul__', '__setattr__', '__str__', 'gr_gid', 'gr_mem', > 'gr_name', 'gr_passwd', 'n_fields', 'n_sequence_fields', > 'n_unnamed_fields'] > >>>> gstat[0] > 'staff' >>>> gstat[GR_GID] > Traceback (most recent call last): > File "<stdin>", line 1, in ? > NameError: name 'GR_GID' is not defined Try gstat.gr_gid, etc > > What's the difference? F_BLOCKS is an attribute of the statvfs module; it is a constant giving the offset into the stats structure. gr_gid is an attribute of the gstat object, it is the actual value that you want. The objects returned by statvfs and getgrgid are unusual in that their attributes can be accessed in two ways, as list values and as object attributes. The list-like access uses brackets [] and an index. In the case of statvfs, the constants are named in the statvfs module; in the case of getgrgid() there don't seem to be symbolic names available. The attribute access uses . notation and an attribute name. You can do stat.f_blocks and gstat.gr_gid. Python takes care of looking up the actual attribute value. I suggest you use the attribute form for both, it is more compact and readable, consistent between both types of objects, and doesn't require the import of statvfs. Kent _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
