KbdSynch: Difference between revisions
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This call synchronizes access from a keyboard subsystem to the keyboard device driver. | This call synchronizes access from a keyboard subsystem to the keyboard device driver. | ||
==Syntax== | ==Syntax== | ||
KbdSynch (IOWait) | KbdSynch (IOWait) | ||
| Line 6: | Line 6: | ||
==Parameters== | ==Parameters== | ||
; IOWait (USHORT) - input : Wait for the bond. Values are: | ; IOWait (USHORT) - input : Wait for the bond. Values are: | ||
::0 - Indicates the requestor does not wait for access to the device driver. | |||
::1 - Indicates the requestor waits for access to the device driver. | |||
==Return Code== | ==Return Code== | ||
;rc (USHORT) - return:Return code descriptions are: | |||
Return code descriptions are: | |||
* 0 NO_ERROR | * 0 NO_ERROR | ||
* 121 ERROR_SEM_TIMEOUT | * 121 ERROR_SEM_TIMEOUT | ||
==Remarks== | ==Remarks== | ||
KbdSynch blocks all other threads within a session until return from the subsystem to the router. To ensure proper synchronization, KbdSynch should be issued by a keyboard subsystem if it intends to issue a DosDevIOCtl or access dynamically shared data. KbdSynch does not protect globally shared data from threads in other sessions. | KbdSynch blocks all other threads within a session until return from the subsystem to the router. To ensure proper synchronization, KbdSynch should be issued by a keyboard subsystem if it intends to issue a [[DosDevIOCtl]] or access dynamically shared data. KbdSynch does not protect globally shared data from threads in other sessions. | ||
== | ==Bindings== | ||
=== C | === C === | ||
<PRE> | <PRE> | ||
#define INCL_KBD | #define INCL_KBD | ||
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USHORT rc = KbdSynch(IOWait); | USHORT rc = KbdSynch(IOWait); | ||
USHORT | USHORT IOWait; /* Indicate if wait */ | ||
USHORT rc; /* return code */ | |||
USHORT | |||
</PRE> | </PRE> | ||
===MASM | ===MASM=== | ||
<PRE> | <PRE> | ||
EXTRN KbdSynch:FAR | EXTRN KbdSynch:FAR | ||
Latest revision as of 16:17, 3 January 2019
This call synchronizes access from a keyboard subsystem to the keyboard device driver.
Syntax
KbdSynch (IOWait)
Parameters
- IOWait (USHORT) - input
- Wait for the bond. Values are:
- 0 - Indicates the requestor does not wait for access to the device driver.
- 1 - Indicates the requestor waits for access to the device driver.
Return Code
- rc (USHORT) - return
- Return code descriptions are:
- 0 NO_ERROR
- 121 ERROR_SEM_TIMEOUT
Remarks
KbdSynch blocks all other threads within a session until return from the subsystem to the router. To ensure proper synchronization, KbdSynch should be issued by a keyboard subsystem if it intends to issue a DosDevIOCtl or access dynamically shared data. KbdSynch does not protect globally shared data from threads in other sessions.
Bindings
C
#define INCL_KBD USHORT rc = KbdSynch(IOWait); USHORT IOWait; /* Indicate if wait */ USHORT rc; /* return code */
MASM
EXTRN KbdSynch:FAR INCL_KBD EQU 1 PUSH WORD IOWait ;Indicate if wait CALL KbdSynch Returns WORD