DosMonOpen: Difference between revisions

Latest revision as of 04:54, 26 January 2020

This call gains access to a character device data stream.

Syntax

DosMonOpen (Devname, Handle)

Parameters

Devname (PSZ) - input: Address of the device name string.
Handle (PHMONITOR) - output: Address of the handle for the monitor. This value must be passed to DosMonReg to communicate with the device, and is passed to DosMonClose to close the connection to the monitor.

Return Code

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

0 - NO_ERROR
110 - ERROR_OPEN_FAILED
379 - ERROR_MON_INVALID_PARMS
380 - ERROR_MON_INVALID_DEVNAME

Remarks

For a detailed description of this call see the chapter "Character Device Monitors" in the IBM Operating System/2 Version 1.2 I/O Subsystems And Device Support Volume 1.

Only one DosMonOpen call is necessary per device per process. That is, several DosMonReg calls can be made using the same monitor handle to the same device. This allows monitors to be registered using different values for Index from the same process and going to the same device. When the DosMonClose is issued, all of the monitors registered on the handle is closed.

Bindings

C

#define INCL_DOSMONITORS

USHORT     rc = DosMonOpen(Devname, Handle);
PSZ        Devname;       /* Device name string */
PHMONITOR  Handle;        /* Monitor handle (returned) */

USHORT     rc;            /* return code */

MASM

EXTRN  DosMonOpen:FAR
INCL_DOSMONITORS    EQU 1

PUSH@  ASCIIZ  Devname    ;Device name string
PUSH@  WORD    Handle     ;Monitor handle (returned)
CALL   DosMonOpen

Returns WORD

@@ Line 1: / Line 1: @@
-==Description==
 This call gains access to a character device data stream.
 ==Syntax==
-<PRE>
+  DosMonOpen (Devname, Handle)
-  DosMonOpen
-    (Devname, Handle)
-</PRE>
 ==Parameters==
-; Devname (PSZ) - input : Address of the device name string.
+;Devname (PSZ) - input: Address of the device name string.
+;Handle (PHMONITOR) - output: Address of the handle for the monitor. This value must be passed to [[DosMonReg]] to communicate with the device, and is passed to [[DosMonClose]] to close the connection to the monitor.
-; Handle (PHMONITOR) - output : Address of the handle for the monitor. This value must be passed to DosMonReg to communicate with the device, and is passed to DosMonClose to close the connection to the monitor.
 ==Return Code==
- rc (USHORT) - return
+;rc (USHORT) - return:Return code descriptions are:
+*0 - NO_ERROR
-Return code descriptions are:
+*110 - ERROR_OPEN_FAILED
+*379 - ERROR_MON_INVALID_PARMS
-* 0     NO_ERROR
+*380 - ERROR_MON_INVALID_DEVNAME
-* 110        ERROR_OPEN_FAILED
-* 379        ERROR_MON_INVALID_PARMS
-* 380        ERROR_MON_INVALID_DEVNAME
 ==Remarks==
-For a detailed description of this call see the chapter "Character Device Monitors" in the IBM Operating System/2 Version 1.2 I/O Subsystems And Device Support Volume 1.
+For a detailed description of this call see the chapter "Character Device Monitors" in the ''IBM Operating System/2 Version 1.2 I/O Subsystems And Device Support Volume 1''.
-Only one DosMonOpen call is necessary per device per process. That is, several DosMonReg calls can be made using the same monitor handle to the same device. This allows monitors to be registered using different values for Index from the same process and going to the same device. When the DosMonClose is issued, all of the monitors registered on the handle is closed.
-==Example Code==
-=== C Binding===
-<PRE>
-#define INCL_DOSMONITORS
-USHORT  rc = DosMonOpen(Devname, Handle);
-PSZ              Devname;       /* Device name string */
-PHMONITOR        Handle;        /* Monitor handle (returned) *
-USHORT           rc;            /* return code */
-</PRE>
-===MASM Binding===
-<PRE>
-EXTRN  DosMonOpen:FAR
-INCL_DOSMONITORS    EQU 1
-PUSH@  ASCIIZ  Devname       ;Device name string
+Only one DosMonOpen call is necessary per device per process. That is, several ''DosMonReg'' calls can be made using the same monitor handle to the same device. This allows monitors to be registered using different values for Index from the same process and going to the same device. When the ''DosMonClose'' is issued, all of the monitors registered on the handle is closed.
-PUSH@  WORD    Handle        ;Monitor handle (returned)
-CALL   DosMonOpen
-Returns WORD
+==Bindings==
-</PRE>
+===C===
+<code>
+ #define INCL_DOSMONITORS
+ USHORT     rc = DosMonOpen(Devname, Handle);
+ PSZ        Devname;       /* Device name string */
+ PHMONITOR  Handle;        /* Monitor handle (returned) */
+ USHORT     rc;            /* return code */
+</code>
-==Related Functions==
+===MASM===
-*
+<code>
+ EXTRN  DosMonOpen:FAR
+ INCL_DOSMONITORS    EQU 1
+ PUSH@  ASCIIZ  Devname    ;Device name string
+ PUSH@  WORD    Handle     ;Monitor handle (returned)
+ CALL   DosMonOpen
+ Returns WORD
+</code>
-[[Category:The OS/2 API Project]]
+[[Category:Dos16]]