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manage your data

Avoid race conditions

Of course...I could
write to the text file
and then immediately call
“put_to_store()” to update
the pickle, right?

Yes, that’s one possible solution, but it’s a poor one.
You might think it highly unlikely…but it is possible for another
process to call the get_from_store() function between the text file
update and the pickle recreation, resulting in a short period of data
inconsistency. These types of situations are known as race conditions
and are hard to debug when they occur.
It’s best to keep them from ever happening if you can.
The basic problem here is that you have one update with one piece of data
that results in two file interactions. If nothing else, that’s just wasteful.

Hey, thanks for What update?!?
the update! It’s been all quiet
over here...

[‘Is this the right room
for an argument?’, “No
you haven’t!”, ‘When?’,
“No you didn’t!”, “You
didn’t!”, ‘You did not!’,
‘Ah! (taking out his wallet
and paying) Just the five
minutes.’, ‘You most
certainly did not!’, “Oh
no you didn’t!”, “Oh no
you didn’t!”, “Oh look,
this isn’t an argument!”,
“No it isn’t!”, “It’s
just contradiction!”,
‘It IS!’, ‘You just
contradicted me!’, ‘You
DID!’, ‘You did just
then!’, ‘(exasperated)
Oh, this is futile!!’,
Your up-to- ‘Yes it is!’]
date text file Your temporarily
inconsistent pickle file
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