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libzmq/doc/zmq_atomic_counter_new.txt

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Problem: need atomic reference counting in several projects Solution: as libzmq already provides this across all platforms, expose an atomic counter API. I've not wrapped atomic pointers, though someone who needs this may want to do so.
2014-12-23 01:14:38 +01:00
zmq_atomic_counter_new(3)
=========================
NAME
----
zmq_atomic_counter_new - create a new atomic counter
SYNOPSIS
--------
*void *zmq_atomic_counter_new (void);*
DESCRIPTION
-----------
The _zmq_atomic_counter_new_ function creates a new atomic counter. You
can use this in multithreaded applications to do, for example, reference
counting of shared objects. The atomic counter is at least 32 bits large.
This function uses platform specific atomic operations.
RETURN VALUE
------------
The _zmq_atomic_counter_new()_ function returns the new atomic counter
if successful. Otherwise it returns NULL.
EXAMPLE
-------
.Test code for atomic counters
----
void *counter = zmq_atomic_counter_new ();
assert (zmq_atomic_counter_value (counter) == 0);
assert (zmq_atomic_counter_inc (counter) == 0);
assert (zmq_atomic_counter_inc (counter) == 1);
assert (zmq_atomic_counter_inc (counter) == 2);
assert (zmq_atomic_counter_value (counter) == 3);
Problem: 'bool' is not defined by default zmq_atomic_counter_dec returned a 'bool' value, yet this isn't defined by standard, so causes compile errors in upstream code. Solution: return an int that can be safely converted to bool if needed by bindings.
2014-12-23 15:20:10 +01:00
assert (zmq_atomic_counter_dec (counter) == 1);
assert (zmq_atomic_counter_dec (counter) == 1);
assert (zmq_atomic_counter_dec (counter) == 0);
Problem: need atomic reference counting in several projects Solution: as libzmq already provides this across all platforms, expose an atomic counter API. I've not wrapped atomic pointers, though someone who needs this may want to do so.
2014-12-23 01:14:38 +01:00
zmq_atomic_counter_set (counter, 2);
Problem: 'bool' is not defined by default zmq_atomic_counter_dec returned a 'bool' value, yet this isn't defined by standard, so causes compile errors in upstream code. Solution: return an int that can be safely converted to bool if needed by bindings.
2014-12-23 15:20:10 +01:00
assert (zmq_atomic_counter_dec (counter) == 1);
assert (zmq_atomic_counter_dec (counter) == 0);
Problem: need atomic reference counting in several projects Solution: as libzmq already provides this across all platforms, expose an atomic counter API. I've not wrapped atomic pointers, though someone who needs this may want to do so.
2014-12-23 01:14:38 +01:00
zmq_atomic_counter_destroy (&counter);
Problem: 'bool' is not defined by default zmq_atomic_counter_dec returned a 'bool' value, yet this isn't defined by standard, so causes compile errors in upstream code. Solution: return an int that can be safely converted to bool if needed by bindings.
2014-12-23 15:20:10 +01:00
return 0;
Problem: need atomic reference counting in several projects Solution: as libzmq already provides this across all platforms, expose an atomic counter API. I've not wrapped atomic pointers, though someone who needs this may want to do so.
2014-12-23 01:14:38 +01:00
----
SEE ALSO
--------
linkzmq:zmq_atomic_counter_set[3]
linkzmq:zmq_atomic_counter_inc[3]
linkzmq:zmq_atomic_counter_dec[3]
linkzmq:zmq_atomic_counter_value[3]
linkzmq:zmq_atomic_counter_destroy[3]
AUTHORS
-------
This page was written by the 0MQ community. To make a change please
read the 0MQ Contribution Policy at <http://www.zeromq.org/docs:contributing>.
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