NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | COLOPHON
VM86(2) Linux Programmer's Manual VM86(2)
vm86old, vm86 - enter virtual 8086 mode
#include <sys/vm86.h>
int vm86old(struct vm86_struct *info);
int vm86(unsigned long fn, struct vm86plus_struct *v86);
The system call vm86() was introduced in Linux 0.97p2. In Linux 2.1.15 and
2.0.28 it was renamed to vm86old(), and a new vm86() was introduced. The
definition of struct vm86_struct was changed in 1.1.8 and 1.1.9.
These calls cause the process to enter VM86 mode (virtual-8086 in Intel
literature), and are used by dosemu.
VM86 mode is an emulation of real mode within a protected mode task.
On success, zero is returned. On error, -1 is returned, and errno is set
appropriately.
EFAULT This return value is specific to i386 and indicates a problem with
getting userspace data.
ENOSYS This return value indicates the call is not implemented on the present
architecture.
EPERM Saved kernel stack exists. (This is a kernel sanity check; the saved
stack should only exist within vm86 mode itself.)
This call is specific to Linux on 32-bit Intel processors, and should not be
used in programs intended to be portable.
This page is part of release 3.23 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
Linux 2009-02-20 VM86(2)