File write, weird behaviour

[Peter J. Holzer]

On 2023-02-19 12:59:43 -0500, Thomas Passin wrote:
> On 2/19/2023 11:57 AM, Axy via Python-list wrote:
> > Looks like the data to be written is buffered, so actual write takes
> > place after readlines(), when close() flushes buffers.
> > 
> > See io package documentation, BufferedIOBase.
> > 
> > The solution is file.flush() after file.write()
> 
> Another possibility, from the Python docs:
> 
> "...TextIOWrapper (i.e., files opened with mode='r+') ... To disable
> buffering in TextIOWrapper, consider using the write_through flag for
> io.TextIOWrapper.reconfigure()"

That actually doesn't help (I tried it before writing my answer). The
binary layer below the text layer also buffers ...

> Also from the docs:
> 
> "Warning: Calling f.write() without using the with keyword or calling
> f.close() might result in the arguments of f.write() not being completely
> written to the disk, even if the program exits successfully."

He does call file.close():

> > > file.close()

so that doesn't seem relevant.

        hp

-- 
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp at hjp.at         |    -- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |       challenge!"
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