tutorial on the use of the Truncate () method of manipulating files in Python

This article mainly introduces the use of the Truncate () method of manipulating files in Python, which is the basic knowledge of Python's introductory study, and needs friends to refer to the following

The truncate () method truncates the size of the file. If an optional dimension parameter exists, the file is truncated (up to) in size.

The size defaults to the current position. The current file location does not change. Note that if a specified size exceeds the current size of the file, the result is dependent on the platform.

Note: This method does not open when the file is working in read-only mode.

Grammar

The following is the syntax for the Truncate () method:

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1	Fileobject.truncate ([size])

Parameters

Size-the size of the file truncated (up to) if an optional parameter exists.

return value

This method does not return any values.

Example

The following example shows the use of the Truncate () method.

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#!/usr/bin/python # Open a file fo = open ("Foo.txt", "rw+") print "Name of the file:", Fo.name # assuming file has fo Llowing 5 Lines # this are 1st line # this is 2nd line # this is 3rd line # the IS 4th . ReadLine () print "Read line:%s"% [line] # now truncate remaining file. Fo.truncate () # Try to read file now = Fo.readline () print ' Read line:%s '% (line) # Close Opend file Fo.close ()

When we run the above program, it produces the following results:

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Name of the File:foo.txt read Line:this is 1st line read: