==== VioModeUndo ====

**Bindings**: [[modeundo#C bindings|C]], [[modeundo#MASM bindings|MASM]]

This call allows one thread within a process to cancel a [[modewait|VioModeWait]] issued by another thread within the same process. 

//VioModeUndo// (OwnerIndic, KillIndic, Reserved) 

//OwnerIndic// (**USHORT**) - input 
Indicates whether the thread issuing [[modeundo|VioModeUndo]] wants ownership of [[modewait|VioModeWait]] to be reserved for its process. 

^Value ^Definition ^
|0 |Reserve ownership |
|1 |Give up ownership. |

//KillIndic// (**USHORT**) - input 
Indicates whether the thread (with the outstanding VioModeWait) should be returned an error code or be terminated. 

^Value ^Definition ^
|0 |Return error code |
|1 |Terminate thread. |

//Reserved// (**USHORT**) - input 
Reserved word of 0s. 

//rc// (**USHORT**) - return 
Return code descriptions are: 

|0 |NO_ERROR |
|421 |ERROR_VIO_INVALID_PARMS |
|422 |ERROR_VIO_FUNCTION_OWNED |
|427 |ERROR_VIO_NO_MODE_THREAD |
|430 |ERROR_VIO_ILLEGAL_DURING_POPUP |
|465 |ERROR_VIO_DETACHED |
|486 |ERROR_VIO_BAD_RESERVE |
|494 |ERROR_VIO_EXTENDED_SG |

**Remarks**

[[modeundo|VioModeUndo]] may be issued only by a thread within the process that owns [[modewait|VioModeWait]]. The thread issuing [[modeundo|VioModeUndo]] can either reserve ownership of the [[modewait|VioModeWait]] function for its process or give up ownership. The thread whose [[modewait|VioModeWait]] is cancelled is optionally terminated. 

=== C bindings ===

<code c>
#define INCL_VIO

USHORT  rc = VioModeUndo(OwnerIndic, KillIndic, Reserved);

USHORT           OwnerIndic;    /* Ownership indicator */
USHORT           KillIndic;     /* Terminate indicator */
USHORT           Reserved;      /* Reserved (must be zero) */

USHORT           rc;            /* return code */
</code>

=== MASM bindings ===

<code asm>
EXTRN  VioModeUndo:FAR
INCL_VIO            EQU 1

PUSH   WORD    OwnerIndic    ;Ownership indicator
PUSH   WORD    KillIndic     ;Terminate indicator
PUSH   WORD    Reserved      ;Reserved (must be zero)
CALL   VioModeUndo

Returns WORD
</code>