software 1. A temporary addition to a piece of code, usually
misfeature. A patch may or may not work, and may or may not
eventually be incorporated permanently into the program.
Distinguished from a
diff or
mod by the fact that a patch
is generated by more primitive means than the rest of the
program; the classical examples are instructions modified by
using the front panel switches, and changes made directly to
the binary executable of a program originally written in an
2. To insert a patch into a piece of code.
3. [in the Unix world] A
diff.
4. A set of modifications to binaries to be applied by a
patching program.
IBM systems often receive updates to the
patches. If you have modified your OS, you have to
might later be corrected by other patches on top of them
(patches were said to "grow scar tissue"). The result was
There is a classic story of a
tiger team penetrating a
secure military computer that illustrates the danger inherent
in binary patches (or, indeed, any patches that you can't - or
don't - inspect and examine before installing). They couldn't
find any
trap doors or any way to penetrate security of
IBM's OS, so they made a site visit to an IBM office
(remember, these were official military types who were
purportedly on official business), swiped some IBM stationery,
and created a fake patch. The patch was actually the trapdoor
they needed. The patch was distributed at about the right
time for an IBM patch, had official stationery and all
accompanying documentation, and was dutifully installed. The
installation manager very shortly thereafter learned something
about proper procedures.
5.
Larry Wall's "patch" utility, which automatically applies
a patch to a set of
source code or other text files. It
accepts input in any of the four forms output by the
Unixhow to apply them.
Diff and patch are the standard way of producing and applying
updates to
Unix files ditributed via
Usenet and the
(1996-06-04)