sarah wrote:
i want to know that what this function returns???
and what does this function do??
rfile.readline()
No way to tell what the function returns from your subject line.
As for what calling it does, that depends entirely on the object rfile.
If it's an instance of a class you wrote, you'll have to look up in your
source code. If it's an instance of one of the built-in system types,
or of a class in the standard library, then you can tell by looking up
that type.
I see standard classes bz2.BZ2File, codecs.StreamReader,
distutils.text_file, file, imaplib, mmap, io.IOBase, io.TextIOBase, and
multifile. These were from the docs for Python 2.6.
Most of these are probably analogous to file, in which case I can elaborate.
If rfile is an instance of file, perhaps by doing
rfile = open("myfile.txt", "r")
then rfile.readline() reads one line from that file, starting at the
current position, and leaves the file position after that line.
readline() stops when it reaches a newline (which it may convert,
depending on the setting of 'rb' versus 'r'), or when it reaches end of
file. The trailing newline (if any) is included in the returned string.
That string may be in byte form (Python 2.x), or in unicode (Python
3.x). In the latter case, it has been decoded according to parameters
of the particular open file.
DaveA
--
http://mail.python.org/mailman/listinfo/python-list
