Python file closing safety

Question

My code looks something like this:

with open(‘myfile.txt’, 'w+') as file:
    file.write("some stuff\n”)
    file.write(“some more stuff”)

The next line in my code opens a subprocess which reads from myfile.txt. I haven’t had any problems yet, but is this safe? Do I need to do something specific to ensure the file is closed so my subprocess won’t read the old version? Should I use Popen and the wait() command? If so, what is proper syntax? I haven’t seen any working examples.

it will automatically close the file. The with statement provides a way for ensuring that a clean-up is always used. — Aaditya Ura, Nov 11 '17 at 22:26
It's best not to use `file` as a name as it's also a builtin function and will shadow it. — Peter Wood, Nov 11 '17 at 23:54

score 1 · Accepted Answer · answered Nov 11 '17 at 22:31

1

This is completely safe. Using 'with ... as ...' automatically closes the file.

If you do not use 'with', you need to close the file manually.

answered Nov 11 '17 at 22:31

score 0 · Answer 2 · answered Nov 11 '17 at 22:32

By utilizing the "with" command you guarantee that after the code following the "with" command is executed, the file you opened will be closed. So, yes it's safe. That's one of the benefits of using it. This stack overflow answer explains it more thoroughly.

Python file closing safety

2 Answers2