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6.5 SCM Mutual Exclusion

These 2 calls can be used for locking and synchronizing processes.

Scheme Procedure: bt:put han key val ¶

Associates key with val in the bt han only if key was previously empty. Returns #t for success, #f for failure.

Scheme Procedure: bt:rem han key ¶

Removes key and it’s associated value from bt han only if key is present. Returns key’s value for success, #f for failure (not present).