How can I create a tmp file in Python?

Question

I have this function that references the path of a file:

some_obj.file_name(FILE_PATH)

where FILE_PATH is a string of the path of a file, i

Answer 1

There is a tempfile module for python, but a simple file creation also does the trick:

new_file = open("path/to/FILE_NAME.ext", "w")

Now you can write to it using the write method:

new_file.write('this is some content')

---

With the tempfile module this might look like this:

import tempfile

new_file, filename = tempfile.mkstemp()

print(filename)

os.write(new_file, "this is some content")
os.close(new_file)

With mkstemp you are responsible for deleting the file after you are done with it. With other arguments, you can influence the directory and name of the file.

---

UPDATE

As rightfully pointed out by Emmet Speer, there are security considerations when using mkstemp, as the client code is responsible for closing/cleaning up the created file. A better way to handle it is the following snippet (as taken from the link):

import os
import tempfile

fd, path = tempfile.mkstemp()
try:
    with os.fdopen(fd, 'w') as tmp:
        # do stuff with temp file
        tmp.write('stuff')
finally:
    os.remove(path)

The os.fdopen wraps the file descriptor in a Python file object, that closes automatically when the with exits. The call to os.remove deletes the file when no longer needed.

Answer 2

I think you're looking for this: http://docs.python.org/library/tempfile.html

import tempfile
with tempfile.NamedTemporaryFile() as tmp:
    print(tmp.name)
    tmp.write(...)

But:

Whether the name can be used to open the file a second time, while the named temporary file is still open, varies across platforms (it can be so used on Unix; it cannot on Windows NT or later).

If that is a concern for you:

import os, tempfile
tmp = tempfile.NamedTemporaryFile(delete=False)
try:
    print(tmp.name)
    tmp.write(...)
finally:
    os.unlink(tmp.name)
    tmp.close()