DESCRIPTION

     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,  and  are
     used by dosemu.

RETURN VALUE

     On success, zero is returned.  On error, -1 is returned, and
     errno is set appropriately.

ERRORS

     (for vm86old)

     EPERM   Saved kernel stack exists. (This is a kernel  sanity
             check; the saved stack should only exist within vm86
             mode itself.)

CONFORMING TO

     This call is specific to  Linux  on  Intel  processors,  and
     should not be used in programs intended to be portable.