test under mask
Also found in: Acronyms.
test under mask[′test ‚ən·dər ′mask]
A procedure for checking the status of selected bits in a byte by comparing the byte with another byte in which these selected bits are set to one and the other bits are set to zero.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.