==== MouSynch ====

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

This call provides synchronous access for a mouse subsystem to the mouse device driver. 

//MouSynch// (IOWait) 

//IOWait// (**USHORT**) - input 
Wait for access. The flag Word is defined as follows: 

^Value ^Definition ^
|0 |Control immediately returned to requestor. |
|1 |Requestor waits until mouse device driver is free. |

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

|0 |NO_ERROR |
|121 |ERROR_SEM_TIMEOUT |

**Remarks** 

[[en:ibm:prcp:mou:synch|MouSynch]] blocks all other threads within a session until the semaphore clears (returns from the subsystem to the router). To ensure proper synchronization, MouSynch should be issued by a mouse subsystem if it intends to access dynamically modifiable shared data for each session or if it intends to issue a [[en:ibm:prcp:cpi:dosdevioctl|DosDevIOCtl]]. [[en:ibm:prcp:mou:synch|MouSynch]] does not protect globally shared data from threads in other sessions. 

=== C bindings ===

<code c>
#define INCL_MOU

USHORT  rc = MouSynch(IOWait);

USHORT           IOWait;        /* Indicate wait/no wait */

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

=== MASM bindings ===

<code asm>
EXTRN  MouSynch:FAR
INCL_MOU            EQU 1

PUSH   WORD    IOWait        ;Indicate wait/no wait
CALL   MouSynch

Returns WORD
</code>