How to lock files (the easiest/best way)?

[Gerhard Fiedler]

On 2006-07-15 18:52:10, Sybren Stuvel wrote:

> Elmo Mäntynen enlightened us with:
>> Only locally. I want to be able to read/write to a single file from
>> multiple possibly parallel processes. Would 'touch lock' (or
>> something like that) work reliably (this just occured to me)?
> 
> I use a lock directory for that, os.mkdir('/var/lock/somedir').
> If you use a file, you need two steps:
>     1) Check whether the lock-file exists
>     2) Create the lock-file

cvsnt for example used to use lock files. Now it uses a lock server: a
server app that just sits there and allows different processes to acquire,
check for and release locks on files. More implementation work, probably,
but more efficient.

Gerhard