<operating system> An integer, string or other small data value which refers to one of several objects allocated to a program by the operating system, usually the kernel. A common example is a Unix file descriptor which is a small integer that identifies an I/O channel. Another example is a reference to an area of memory (e.g. shared memory).
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Nearby terms: descent function « Descriptive Intermediate Attributed Notation for Ada « Descriptive Top-Level Specification « descriptor » design » Design In Real Time » design pattern