PEEK
The command in most microcomputer BASICs for reading memory contents (a byte) at
an absolute address. POKE is the corresponding command to write a value to an
absolute address.
This is often extended to mean the corresponding constructs in any High Level
Language.
Much hacking on small microcomputers without MMUs consists 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 circulate (see interrupt list). The results of "poke"s at
these addresses may be highly useful, mildly amusing, useless but neat, or 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, operating system kernels often
have to do exactly this; a real C hacker would unhesitatingly, if unportably,
assign an absolute address to a pointer variable and indirect through it.
[Jargon File]
(1995-01-31)
Nearby terms:
PEBKAC « PECOS « Pedagogic Algorithmic Language «
PEEK
» PEEL » peephole optimisation » peer
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