Python 2.7 : Write to file instantly

Question

I realized that when I write into a file using python it wait until the end of my Python file to execute it:

outputFile = open(\"./outputFile.txt\",\"a\")
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Answer 1

As @RyPeck said you can use flush() or set the file object to be unbuffered. But note the following (from https://docs.python.org/2/library/stdtypes.html?highlight=file%20flush#file.flush):

Flush the internal buffer, like stdio‘s fflush().

Note flush() does not necessarily write the file’s data to disk. Use flush() followed by os.fsync() to ensure this behavior.

And a quote from man 3 fflush:

Note that fflush() only flushes the user-space buffers provided by the C library. To ensure that the data is physically stored on disk the kernel buffers must be flushed too, for example, with sync(2) or fsync(2).