File object question

[S. D. Rose]

Hello all.
If I read a binary file:

file = open('c:\\logo.gif', 'rw'') # Read from FS as one way to get the
object, d/l from website another...
file.read()

is there anyway I can determine the 'size' of the object file? (Without
going to the filesystem and reading the filesize from the directory ...)

Thanks!

 

[mrmakent]

See http://www.python.org/doc/2.4.2/lib/os-file-dir.html for the 'stat'
function

import os
os.stat(path).st_size

This will return the size in bytes of the file designated by 'path'.

 

[Kent Johnson]

Hello all.
If I read a binary file:

file = open('c:\\logo.gif', 'rw'') # Read from FS as one way to get the
object, d/l from website another...
file.read()

is there anyway I can determine the 'size' of the object file? (Without
going to the filesystem and reading the filesize from the directory ...)

Once you have read the data you can get the size of that:
d = file.read()
print len(d)

Is that what you mean? Otherwise I don't know how you can get the size of a file without
asking the filesystem...

Kent

 

[S. D. Rose]

Yes, len() will do what I want. I didn't realize it would work with binary,
I thought it was good only for variables, lists, etc.

Thanks!
-Dave

 

[Ben Hutchings]

Yes, len() will do what I want. I didn't realize it would work with binary,

The read() function returns a string (object of type str), whether the
file was opened in binary or text mode. Such objects are really a
series of bytes which may or may not represent text in some encoding.
(By contrast, objects of type unicode definitely do represent text in
some Unicode encoding.)

I thought it was good only for variables, lists, etc.

Variables? Do you mean tuples? len() works with any kind of sequence,
and strings behave as a sequence of 1-byte strings.