The following errors have been found in the first print run of the Fourth Edition:

Page 110 - section 4.4.3

Replace 'a vary dangerous' with 'a very dangerous'.

Page 336

The waitForNextPeriod and waitForNextRelease methods in Program 10.1 should be static methods.

Page 447 - line 19

replace '- task T has an earlier deadline than task S;' with '- task T has an earlier deadline than task S and all other tasks on ready queues with priorities strictly less than R;'.

Page 449 - line -10 (i.e. 10 from bottom)

Replace '(at priority 2, or 4 if it' with '(at priority 2, or 3 if it'.

Please report any errors to Alan Burns or Andy Wellings.