zmq_has - check a ZMQ capability


int zmq_has (const char *capability);


The zmq_has() function shall report whether a specified capability is available in the library. This allows bindings and applications to probe a library directly, for transport and security options.

Capabilities shall be lowercase strings. The following capabilities are defined:

  • ipc - the library supports the ipc:// protocol

  • pgm - the library supports the pgm:// protocol

  • tipc - the library supports the tipc:// protocol

  • norm - the library supports the norm:// protocol

  • curve - the library supports the CURVE security mechanism

  • gssapi - the library supports the GSSAPI security mechanism

  • draft - the library is built with the draft api

When this method is provided, the zmq.h header file will define ZMQ_HAS_CAPABILITIES.


The zmq_has() function shall return 1 if the specified capability is provided. Otherwise it shall return 0.


This page was written by the 0MQ community. To make a change please read the 0MQ Contribution Policy at