i386_get_ioperm2
Manage per-process access to the i386 i/o port space
Usage
#include <machine/sysarch.h>
int
i386_get_ioperm(unsigned int start, unsigned int *length, int *enable);
int
i386_set_ioperm(unsigned int start, unsigned int length, int enable);
Library
Standard C Library (libc, -lc)
Overview
The i386_get_ioperm() system call will return the permission for the process' I/O port space in the *enable argument. The port range starts at start and the number of contiguous entries will be returned in *length.
The i386_set_ioperm() system call will set access to a range of I/O ports described by the start and length arguments to the state specified by the enable argument.
Return values
The i386_get_ioperm() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error.
Errors
The i386_get_ioperm() and i386_set_ioperm() system calls will fail if:
- [EINVAL]
-
An invalid range was specified by the start or length arguments.
- [EPERM]
-
The caller of i386_set_ioperm was not the superuser.