# What is function of 'bit_mask' in event functions?

Question asked by Steve Janisch on Sep 12, 2013
Latest reply on Sep 13, 2013 by David E Seymour
Branched to a new discussion

Several MQX event functions (e.g. _event_wait_all, _event_clear, _event_set) have an argument _mqx_uint bit_mask.

The reference manual only gives a cryptic definition for this argument:

"Each set bit represents an event bit to clear"

Most of the examples use the constant 0x01 for the bit_mask argument, so there is no help there.

Does anyone know precisely what this argument does?