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Returns the number of characters in the transmit queue.  
{{DISPLAYTITLE:ASYNC_GETOUTQUECOUNT}}
 
Returns the number of characters in the transmit queue.
; Category: IOCTL_ASYNC (01h)  
;Category: IOCTL_ASYNC (01h)
; Function: ASYNC_GETOUTQUECOUNT (69h)  
;Function: ASYNC_GETOUTQUECOUNT (69h)


==Parameter Packet Format==
==Parameter Packet Format==
None. Packet pointer must be NULL.  
None. Packet pointer must be NULL.


==Data Packet Format==
==Data Packet Format==
<pre>
{|class="wikitable"
┌──────────────────────────────────────────────────────┐
!Field||Length||C Datatype
│Field                          Length     C Datatype
|-
├──────────────────────────────────────────────────────┤
|Number of Characters Queued||WORD||USHORT
│Number of Characters Queued   WORD       USHORT     │
|-
├──────────────────────────────────────────────────────┤
|Size of Transmit Queue||WORD||USHORT
│Size of Transmit Queue         WORD       USHORT     │
|}
└──────────────────────────────────────────────────────┘
;Related C Data Structure:The RXQUEUE data structure can be used by C programmers.
</pre>
:To include this data structure in your file, make sure INCL_DOSDEVIOCTL is defined before you include OS2.H.
;Related C Data Structure  
 
The RXQUEUE data structure can be used by C programmers.  
 
To include this data structure in your file, make sure INCL_DOSDEVIOCTL is defined before you include OS2.H.
 
;Number of Characters Queued
Binary integer with the number of characters ready to be transmitted in the physical device driver transmit queue. This is a memory buffer between the memory pointed to by the WRITE request packet and the transmit hardware for this COM device. If the transmit queue is empty, the application cannot assume that all Write requests have completed or that no Write requests are outstanding.
 
:;Note ::The behavior of data movement between the Write request and the transmit queue can change with each release of the physical device driver. Applications should not be dependent on this information.  


;Size of Transmit Queue  
;Number of Characters Queued:Binary integer with the number of characters ready to be transmitted in the physical device driver transmit queue. This is a memory buffer between the memory pointed to by the WRITE request packet and the transmit hardware for this COM device. If the transmit queue is empty, the application cannot assume that all Write requests have completed or that no Write requests are outstanding.
Binary integer with the size of the physical device driver transmit queue. Applications should be independent of the transmit queue size (fixed or not fixed). The information in this field allows the application to get the size of the transmit queue, but is subject to change.  
:;Note:The behavior of data movement between the Write request and the transmit queue can change with each release of the physical device driver. Applications should not be dependent on this information.
;Size of Transmit Queue:Binary integer with the size of the physical device driver transmit queue. Applications should be independent of the transmit queue size (fixed or not fixed). The information in this field allows the application to get the size of the transmit queue, but is subject to change.


==Returns==
==Returns==
If the call is made with an invalid Parameter Packet value, a general failure error is reported and valid information is not returned in the Data Packet.  
If the call is made with an invalid Parameter Packet value, a general failure error is reported and valid information is not returned in the Data Packet.


==Remarks==
==Remarks==
If a general failure error is not returned, the physical device driver returns the information.  
If a general failure error is not returned, the physical device driver returns the information.


[[Category:IOCtl Commands]]
[[Category:IOCtl Function]]
{{DISPLAYTITLE:ASYNC_GETOUTQUECOUNT (69h)}}

Latest revision as of 18:57, 22 October 2021

Returns the number of characters in the transmit queue.

Category
IOCTL_ASYNC (01h)
Function
ASYNC_GETOUTQUECOUNT (69h)

Parameter Packet Format

None. Packet pointer must be NULL.

Data Packet Format

Field Length C Datatype
Number of Characters Queued WORD USHORT
Size of Transmit Queue WORD USHORT
Related C Data Structure
The RXQUEUE data structure can be used by C programmers.
To include this data structure in your file, make sure INCL_DOSDEVIOCTL is defined before you include OS2.H.
Number of Characters Queued
Binary integer with the number of characters ready to be transmitted in the physical device driver transmit queue. This is a memory buffer between the memory pointed to by the WRITE request packet and the transmit hardware for this COM device. If the transmit queue is empty, the application cannot assume that all Write requests have completed or that no Write requests are outstanding.
Note
The behavior of data movement between the Write request and the transmit queue can change with each release of the physical device driver. Applications should not be dependent on this information.
Size of Transmit Queue
Binary integer with the size of the physical device driver transmit queue. Applications should be independent of the transmit queue size (fixed or not fixed). The information in this field allows the application to get the size of the transmit queue, but is subject to change.

Returns

If the call is made with an invalid Parameter Packet value, a general failure error is reported and valid information is not returned in the Data Packet.

Remarks

If a general failure error is not returned, the physical device driver returns the information.