computer science Computer science is the study of computation, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, ...

, the concept of protected procedure, first introduced as protected service routine in 1965, is necessary when two computations ''A'' and ''B'' use the same routine ''S''; a protected procedure is such if makes not possible for a malfunction of one of the two computation to cause incorrect execution to the other.Dennis 66 One of the most important aspects of Dennis and Van Horn (hypothetical) system "supervisor" was the inclusion of a description of protected procedure.Levy 84, pp.46-6 In a global environment system (where there's some shared variable), the protected procedure mechanism allows the enforcement of the

principle of least privilege In information security, computer science, and other fields, the principle of least privilege (PoLP), also known as the principle of minimal privilege (PoMP) or the principle of least authority (PoLA), requires that in a particular abstraction l ...

and the avoidance of

side effects In medicine, a side effect is an effect of the use of a medicinal drug or other treatment, usually adverse but sometimes beneficial, that is unintended. Herbal and traditional medicines also have side effects. A drug or procedure usually used ...

in resources management (see Denning principles).

Footnotes

References

* Dennis, J. B., and Glasee, E. ''The structure of on-line information processing systems''. Information Systems Sciences: Proc. Second Cong., Spartan Books, Baltimore, 1965, pp. 1–11 *J. B. Dennis and E. C. Van Horn.
Programming Semantics for Multiprogrammed Computations
'. Communications of the ACM 9(3), March 1966. * Concurrent computing Subroutines {{compu-sci-stub