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arch(3): document msr

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cinap_lenrek 2011-08-27 07:42:13 +02:00
parent 78e19b52bf
commit c8168fd3bc
1 changed files with 6 additions and 1 deletions
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7
sys/man/3/arch
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@ -12,6 +12,7 @@ arch \- architecture-specific information and control
.B /dev/iol
.B /dev/iow
.B /dev/irqalloc
.B /dev/msr
.SH DESCRIPTION
This device presents textual information about PC hardware and allows
user-level control of the I/O ports on x86-class and DEC Alpha machines.
@ -116,11 +117,15 @@ Reads and writes to
.IR iob ,
.IR iow ,
and
.I iol
.IR iol
cause 8-bit wide, 16-bit wide, and 32-bit wide requests to
I/O ports.
The port accessed is determined by the byte offset of the
file descriptor.
.PP
Reads and writes to
.I msr
go to the P4/P6/Core/Core2/AMD64 MSRs.
.SH EXAMPLE
The following code reads from an x86 byte I/O port.
.IP