On 07Jul2024 22:22, Rob Cliffe wrote:
it's legal, but doesn't work (trying to access the file after "with f"
raises the same
ValueError: I/O operation on closed file.
Just to this: of course. The with closes the file. But my version runs
the with after the try/except.
--
https://mail.py
On 07Jul2024 22:22, Rob Cliffe wrote:
Remember, the `open()` call returns a file object _which can be used
as a context manager_. It is separate from the `with` itself.
Did you test this?
f = open(FileName) as f:
is not legal syntax.
No. You're right, remove the "as f:".
it's legal, but
On 2024-07-07 23:27, Barry via Python-list wrote:
On 7 Jul 2024, at 22:13, Chris Green via Python-list
wrote:
a simple file lock can then
be used to prevent simultaneous access (well, simultaneous access when
the writing process is writing).
There is a simple pattern to make this robust.
> On 7 Jul 2024, at 22:13, Chris Green via Python-list
> wrote:
>
> a simple file lock can then
> be used to prevent simultaneous access (well, simultaneous access when
> the writing process is writing).
There is a simple pattern to make this robust.
Write new values to a tmp file.
Close th
On 07/07/2024 02:08, Cameron Simpson wrote:
On 06Jul2024 11:49, Rob Cliffe wrote:
try:
f = open(FileName) as f:
FileLines = f.readlines()
except FileNotFoundError:
print(f"File {FileName} not found")
sys.exit()
# I forgot to put "f.close()" here -:)
for ln in File Lines:
On 06/07/2024 12:32, Stefan Ram wrote:
But why overengineer? If you feel comfortable with the file
solution, go for it! The only drawback might be that it's a
bit slower than other approaches.
I absolutely agree. Overengineering is generally a bad idea because
you're using a complex s
On 06/07/2024 09.28, Chris Green wrote:
I have a Raspberry Pi in my boat that uses I2C to read a number of
voltages and currents (using ADS1115 A2D) so I can monitor the battery
condition etc.
At present various different scripts (i.e. processes) just read the
values using the I2C bus whenever t
I have a Raspberry Pi in my boat that uses I2C to read a number of
voltages and currents (using ADS1115 A2D) so I can monitor the battery
condition etc.
At present various different scripts (i.e. processes) just read the
values using the I2C bus whenever they need to but I'm pretty sure
this (quit
