A comprehensive examination of UNIX system calls - the interface between user programs and the kernel.* features in-depth coverage of AT&T Systems III and V, IBMs PC/IX, and Microsofts Xenix 3. offers practical advice on how and when to use - and not use - system calls, based on the authors extensive experience with UNIX. provides hints on making applications portable. emphasizes strengths and limitations of UNIX. explains the rationale behind many UNIX design features. contains a logical grouping of system calls to facilitate study in conjunction with operating system texts. contains over 100 detailed, tested example programs.