document support for NULL free function in zmq_msg_init_data

Description

The zmq_msg_init_data API function has a zmq_free_fn argument that is a pointer to a function to free the data. It would be good to document and officially support the feature (ALREADY IMPLEMENTED in the source code) that passing NULL for this argument is allowed and simply means that no free function is called.

I checked the source code for both version 2.2.0 and 3.2.3, and NULL free-function arguments are supported in both.

Environment

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Status

Assignee

Unassigned

Reporter

Steven G. Johnson

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Components

Priority

Minor
Configure