threading id generator ?

[Andrea Manzini]

Hi all,

I'm a python newbie with a little problem; my need is to share an incrementing counter between threads; i.e. every time I create a new thread (which handle a single tcp/ip connection), I must assign an unique numeric ID to it, without reuse old numbers... In example:

thread-1 id: 1
thread-2 id: 2
thread-3 id: 3
thread-100 id: 100
thread-n id: n

which locking semantic I must use to implement a shared generator in a thread ?

thanks in advance


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[Diez B. Roggisch]

which locking semantic I must use to implement a shared generator in a

thread ?

thanks in advance

You could try something like this:

class IdGen:
def __init__(_):
_.lock = threading.Lock()
_.id = 0

def id_gen(_):
_.lock.aqcuire()
new_id = _.id
_.id += 1
lock.release()
return new_id


An instance of IdGen you could store in a global variable. Or you make it a
singleton. Or you pass one instance around for all your threading-objects.
Or you make _.id and _.lock class-variables, and inherit all your
threading-objects from IdGen. Or you make it a module.... and so on

 

[Alan Kennedy]

[Andrea Manzini]

> I'm a python newbie with a little problem; my need is to share an
> incrementing counter between threads; i.e. every time I create a
> new thread (which handle a single tcp/ip connection), I must assign
> an unique numeric ID to it, without reuse old numbers... In example:
>
> thread-1 id: 1
> thread-2 id: 2
> thread-3 id: 3
> thread-100 id: 100
> thread-n id: n
>
> which locking semantic I must use to implement a shared generator
> in a thread ?

This came up about a month ago. Group-Googling for ("shared generator"
and "multiple threads") gives useful results.

http://groups.google.com/groups?hl=...ltiple+threads"&meta=group=comp.lang.python.*

regards,