File Positions in Python 3
The tell() method tells you the current position
within the file; in other words, the next read or write will occur at that many bytes from the
beginning of the file.
The seek(offset[, from]) method changes the current
file position. The offset argument indicates the number of bytes to be moved. The from
argument specifies the reference position from where the bytes are to be moved.
If from is
set to 0, the beginning of the file is used as the reference position. If it is
set to 1, the current position is used as the reference position. If it is set
to 2 then the end of the file would be taken as the reference position.
Example
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#!/usr/bin/python3
# Open a
file
fo =
open("foo.txt", "r+")
str =
fo.read(10)
print
("Read String is : ", str)
# Check
current position
position
= fo.tell()
print
("Current file position : ", position)
#
Reposition pointer at the beginning once again
position
= fo.seek(0, 0)
str =
fo.read(10)
print
("Again read String is : ", str)
# Close
opened file
fo.close()
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Let us take a file foo.txt, which we created above.
This produces the following result-
|
Read
String is : Python is
Current
file position : 10
Again
read String is : Python is
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