Working with Files in Python
To work with a file, you must open it using a special built-in function:
open(file, mode='r', buffering=-1, encoding=None, errors=None, newline=None, closefd=True, opener=None)
Opens a file and returns an object representing it.
| File Opening Modes | |
|---|---|
| r | open a file for reading |
| w | open a file for writing; the file content is deleted. If the file does not exist, a new one is created |
| x | open a file for writing if the file does not exist. If the file exists, an exception is raised |
| b | open a file in binary mode |
| t | open a file in text mode |
| + | open a file for reading and writing |
File Object Methods
file.read (size)
Reads and returns information from the file. If the optional size parameter is specified, it returns only the specified number of characters/bytes.
file.write (content)
Writes information to the file.
file.tell ()
Returns the current pointer position within the file.
file.seek (position, from_what=0)
Moves the pointer to the specified position. The first argument is the number of positions to move the pointer. If this argument is positive, the pointer moves to the right; if negative, to the left.
The second, optional argument is from_what. It specifies where to move the pointer from: 0 — from the beginning of the file, 1 — from the current position, and 2 — from the end of the file. By default, this argument is 0.
file.close ()
Closes the file. You must call this method after finishing work with the file.