I386_VM86(2) BSD System Calls Manual I386_VM86(2)NAMEi386_vm86 — control vm86-related functions
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/types.h>
#include <machine/sysarch.h>
#include <machine/vm86.h>
int
i386_vm86(int function, void *data);
DESCRIPTIONi386_vm86() is used to call various vm86 related functions. function can
be one of the following values:
VM86_INIT This will initialize the kernel's vm86 parameter area
for the process, and permit the process to make vm86
calls. data points to the following structure:
struct vm86_init_args {
int debug;
int cpu_type;
u_char int_map[32];
};
debug is used to turn on debugging code. cpu_type
controls the type of CPU being emulated, and is cur‐
rently unimplemented. int_map is a bitmap which
determines whether vm86 interrupts should be handled
in vm86 mode, or reflected back to the process. If
the Nth bit is set, the interrupt will be reflected
to the process, otherwise it will be dispatched by
the vm86 interrupt table.
vm86 mode is entered by calling sigreturn(2) with the correct machine
context for vm86, and with the PSL_VM bit set. Control returns to the
process upon delivery of a signal.
RETURN VALUES
The i386_vm86() function returns the value 0 if successful; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.
ERRORSi386_vm86() will fail if:
[EINVAL] The kernel does not have vm86 support, or an invalid
function was specified.
[ENOMEM] There is not enough memory to initialize the kernel
data structures.
AUTHORS
This man page was written by Jonathan Lemon.
BSD July 27, 1998 BSD
