NAME
outb, outw, outl, outsb, outsw, outsl - port output
inb, inw, inl, insb, insw, insl - port input
outb_p, outw_p, outl_p, inb_p, inw_p, inl_p - paused I/O
DESCRIPTION
This family of functions is used to do low level port input
and output. They are primarily designed for internal kernel
use, but can be used from user space, given the following
information in addition to that given in outb(9)
You compile with -O or -O2 or similar. The functions are
defined as inline macros, and will not be substituted in
without optimization enabled, causing unresolved references
at link time.
You use ioperm(2) or alternatively iopl(2) to tell the ker-
nel to allow the user space application to access the I/O
ports in question. Failure to do this will cause the appli-
cation to receive a segmentation fault.
CONFORMING TO
outb and friends are hardware specific. The port and value
arguments are in the opposite order to most DOS implementa-
tions.
SEE ALSO
outb(9), ioperm(2), iopl(2)