Determines whether the given timer handle is valid.
A handle that is invalid will result in no operations being carried out
when used. In particular addRef/releaseRef will have no effect, but
can safely be called.
A valid handle gets invalid when the reference count drops to zero.
Determines whether the given timer handle is valid.
A handle that is invalid will result in no operations being carried out when used. In particular addRef/releaseRef will have no effect, but can safely be called.
A valid handle gets invalid when the reference count drops to zero.