Peek N.,vt. (and Poke) The Commands In Most Microcomputer BASICs For Directly Accessing Memory Contents At An Absolute Addre

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peek n.,vt.

(and poke) The commands in most
microcomputer BASICs for directly accessing memory contents at an
absolute address; often extended to mean the corresponding
constructs in any HLL (peek reads memory, poke modifies it).
Much hacking on small, non-MMU micros used to consist of `peek'ing
around memory, more or less at random, to find the location where
the system keeps interesting stuff. Long (and variably accurate)
lists of such addresses for various computers circulated (see
interrupt list). The results of `poke's at these
addresses may be highly useful, mildly amusing, useless but neat,
or (most likely) total lossage (see killer poke).

Since a real operating system provides useful, higher-level
services for the tasks commonly performed with peeks and pokes on
micros, and real languages tend not to encourage low-level memory
groveling, a question like "How do I do a peek in C?" is
diagnostic of the newbie. (Of course, OS kernels often have to
do exactly this; a real kernel hacker would unhesitatingly, if
unportably, assign an absolute address to a pointer variable and
indirect through it.)

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