>> +.. function:: get_ident()
>> +
>> + Return the 'thread identifier' of the current thread. This is a nonzero
>> + integer. Its value has no direct meaning; it is intended as a magic
>> cookie
>> + to be used e.g. to index a dictionary of thread-specific data. Thread
>> + identifiers may be recycled when a thread exits and another thread is
>> + created.
>
> That's not quite true - the Thread id isn't relinquished until the
> Thread object itself is destroyed, rather than when the underlying
> thread finishes execution (i.e. the lifecycle of a_thread.ident is the
> same as that of id(a_thread)).
>
I'm not sure I understand, Nick.
Since threads are started detached, their thread ID (e.g. returned by
pthread_self() on pthreads) can be reused as soon as the underlying OS
thread exits (i.e. returns from Modules/_threadmodule.c:t_boostrap) :
On a Linux kernel with NPTL:
$ cat /tmp/test.py
import threading
def print_ident():
print(threading._get_ident())
t1 = threading.Thread(target=print_ident)
t2 = threading.Thread(target=print_ident)
t1.start()
t1.join()
t2.start()
t2.join()
print(id(t1), id(t2))
$ ./python /tmp/test.py
-1211954272
-1211954272
(3085561228L, 3083093028L)
I'm just curious, maybe I missed something?
Thanks,
cf
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