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I386_IOPL(2) System Calls Manual (i386) I386_IOPL(2) NAME i386_iopl - change the i386 I/O privilege level LIBRARY i386 Architecture Library (libi386, -li386) SYNOPSIS #include <sys/types.h> #include <machine/sysarch.h> int i386_iopl(int iopl); DESCRIPTION i386_iopl() sets the i386 I/O privilege level to the value specified by iopl. This call is restricted to the super-user. RETURN VALUES Upon successful completion, i386_iopl() returns 0. Otherwise, a value of -1 is returned and the global variable errno is set to indicate the error. ERRORS i386_iopl() will fail if: [EPERM] The caller was not the super-user, or the operation was not permitted at the current security level. REFERENCES i386 Microprocessor Programmer's Reference Manual, Intel WARNING You can really hose your machine if you enable user-level I/O and write to hardware ports without care. NetBSD 10.99 April 12, 2004 NetBSD 10.99