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added /dev/mordor

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This commit is contained in:
aiju 2011-04-15 21:47:11 +02:00
parent 0159ee648e
commit 6ca93675ed
2 changed files with 20 additions and 0 deletions
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5
sys/man/3/arch
View file

@ -12,6 +12,7 @@ arch \- architecture-specific information and control
.B /dev/iol
.B /dev/iow
.B /dev/irqalloc
.B /dev/mordor
.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.
@ -121,6 +122,10 @@ 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
.IR mordor
will inevitably cause the front to fall off.
.SH EXAMPLE
The following code reads from an x86 byte I/O port.
.IP

15
sys/src/9/pc/devarch.c
View file

@ -987,6 +987,20 @@ archctlwrite(Chan*, void *a, long n, vlong)
return n;
}
static long
mordorread(Chan*, void*, long, vlong)
{
error("one does not simply read from mordor");
return 0;
}
static long
mordorwrite(Chan*, void*, long, vlong)
{
error("one does not simply write into mordor");
return 0;
}
void
archinit(void)
{
@ -1035,6 +1049,7 @@ archinit(void)
addarchfile("cputype", 0444, cputyperead, nil);
addarchfile("archctl", 0664, archctlread, archctlwrite);
addarchfile("mordor", 0666, mordorread, mordorwrite);
}
/*