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Diffstat (limited to 'man2/vm86.2')
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diff --git a/man2/vm86.2 b/man2/vm86.2 new file mode 100644 index 000000000..6709d5467 --- /dev/null +++ b/man2/vm86.2 @@ -0,0 +1,69 @@ +.\" Hey Emacs! This file is -*- nroff -*- source. +.\" +.\" Copyright 1993 Rickard E. Faith (faith@cs.unc.edu) +.\" Copyright 1997 Andries E. Brouwer (aeb@cwi.nl) +.\" +.\" Permission is granted to make and distribute verbatim copies of this +.\" manual provided the copyright notice and this permission notice are +.\" preserved on all copies. +.\" +.\" Permission is granted to copy and distribute modified versions of this +.\" manual under the conditions for verbatim copying, provided that the +.\" entire resulting derived work is distributed under the terms of a +.\" permission notice identical to this one. +.\" +.\" Since the Linux kernel and libraries are constantly changing, this +.\" manual page may be incorrect or out-of-date. The author(s) assume no +.\" responsibility for errors or omissions, or for damages resulting from +.\" the use of the information contained herein. The author(s) may not +.\" have taken the same level of care in the production of this manual, +.\" which is licensed free of charge, as they might when working +.\" professionally. +.\" +.\" Formatted or processed versions of this manual, if unaccompanied by +.\" the source, must acknowledge the copyright and authors of this work. +.\" +.TH VM86 2 1997-07-17 "Linux 2.1.15" "Linux Programmer's Manual" +.SH NAME +vm86old, vm86 \- enter virtual 8086 mode +.SH SYNOPSIS +.B #include <sys/vm86.h> +.sp +.BI "int vm86old(struct vm86_struct *" info ); +.sp +.BI "int vm86(unsigned long " fn ", struct vm86plus_struct *" v86 ); +.SH DESCRIPTION +The system call +.B vm86 +was introduced in Linux 0.97p2. In Linux 2.1.15 and 2.0.28 it was renamed to +.BR vm86old , +and a new +.B vm86 +was introduced. The definition of `struct vm86_struct' was changed +in 1.1.8 and 1.1.9. +.LP +These calls cause the process to enter VM86 mode (virtual-8086 in Intel +literature), and are used by +.BR dosemu . +.PP +VM86 mode is an emulation of real mode within a protected mode task. +.SH "RETURN VALUE" +On success, zero is returned. On error, \-1 is returned, and +.I errno +is set appropriately. +.SH ERRORS +.TP +.B EFAULT +This return value is specific to i386 and indicates a problem with getting +userspace data. +.TP +.B ENOSYS +This return value indicates the call is not implemented on the present +architecture. +.TP +.B EPERM +Saved kernel stack exists. (This is a kernel sanity check; the saved +stack should only exist within vm86 mode itself.) +.SH "CONFORMING TO" +This call is specific to Linux on Intel processors, and should not be +used in programs intended to be portable. |