DevHelp QueueInit
From EDM2
This service initializes the specified character queue structure.
Contents
Syntax
C
USHORT APIENTRY DevHelp_QueueInit (NPBYTE Queue)
Assembler
MOV BX,OFFSET DS:queue ; Points to the queue structure to be initialized. ; (The Qsize field must be set up.) MOV DL,DevHlp_QueueInit CALL [Device_Help]
Parameters
C
- Queue (NPBYTE)
- input - Near pointer to the queue structure to be initialized. (The Qsize field must be set up.)
Assembler
MOV BX,OFFSET DS:queue ; Points to the queue structure to be initialized. ; (The Qsize field must be set up.)
Return Code
C
None .
Assembler
None .
Remarks
This function must be called before any other queue manipulation subroutine. Prior to this call, the physical device driver must allocate the character queue buffer with the following queue header:
type def struct_QUEUEHDR{ USHORT QSize; USHORT QChrOut; USHORT QCount; BYTE Queue [1]; }QUEUEHDR;
The Qsize field should be initialized by the physical device driver before calling QueueInit.
Example Code
C
USHORT APIENTRY DevHelp_QueueInit (NPBYTE Queue) typedef struct _QUEUEHDR { /* DHQH */ USHORT QSize; USHORT QChrOut; USHORT QCount; BYTE Queue[1]; } QUEUEHDR; typedef QUEUEHDR *PQUEUEHDR;