Race condition
Race conditions arise in software when an application depends on the sequence or timing of processes or threads for it to operate properly. As with electronics, there are critical race conditions that result in invalid execution and bugs. Critical race conditions often happen when the processes or threads depend on some shared state. Operations upon shared states are critical sections that must be mutually exclusive. Failure to obey this rule opens up the possibility of corrupting the shared state.
Post-Blackness
In "Race and Mixed Race" "The Kinship Schema", Naomi Zack attempts to explain why a person is considered black or white:
“If a person has a black parent, a black grandparent, or a black greatn -grandparent (where n represents any number of past generations), then that person is designated black. But if a person has a white parent, or three white grandparents, or Z white greatn -grandparents (where Z is any odd number and n still represents any number of past generations), then that person is not thereby designated white.”
According to this definition, a person is white if no black ancestors exist, whereas one black person (or "non-white" person) in the line makes or person black, or at least not white anymore.