\ BooknewsDescribes general computer requirements for time-critical applications and related requirements for real-time operating systems. Major weaknesses of the standard UNIX System V for real-time applications are discussed, and various approaches in designing real-time UNIX operating systems are presented. The REAL/IX operating system, a fully preemptive real-time UNIX operating system, is described in detail. Two detailed case studies of designing real-time systems are included. Annotation c. Book News, Inc., Portland, OR (booknews.com)\ \