<jargon, memory management> A small piece of data inserted in order to achieve a desired memory alignment or other addressing property.
For example, the PDP-11 Unix linker, in split I&D (instructions and data) mode, inserts a two-byte shim at location 0 in data space so that no data object will have an address of 0 (and be confused with the C null pointer).
See also loose bytes.
(1994-12-21)
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