The mmap Module
The mmap
module supplies memory-mapped file objects. An mmap
object behaves similarly to a plain (not Unicode) string, so you can often pass an mmap
object where a plain string is expected. However, there are differences:
An
mmap
object does not supply the methods of a string object.An
mmap
object is mutable, while string objects are immutable.An
mmap
object also corresponds to an open file and behaves polymorphically to a Python file object (as covered in File-Like Objects and Polymorphism).
An mmap
object m
can be indexed or sliced, yielding plain strings. Since m
is mutable, you can also assign to an indexing or slicing of m
. However, when you assign to a slice of m
, the righthand side of the assignment statement must be a string of exactly the same length as the slice you’re assigning to. Therefore, many of the useful tricks available with list slice assignment (covered in Modifying a list) do not apply to mmap
slice assignment.
Module mmap
supplies a factory function that is slightly different on Unix-like systems and Windows.
mmap |
Creates and returns an |
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