qdosmsq:traps:trap_3:xinf [QDOS Internals]

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
====== IOF_XINF ======


This trap returns extended filing system information.

^Call Parameters^^Return Parameters^^
|D0.B|$4F|D0.L|Error return.|
|D1.L|0|D1.L|Preserved.|
|D3.W|Timeout |D2.L|Preserved.|
|A0.L|Channel ID |A0.L|Preserved.|
|A1.L|Address of buffer|A1.L|Preserved.|
===== Errors =====
Any I/O subsystem errors including

|ERR_NC|Not complete.|


===== Notes =====
  * All registers not shown above are not used on entry and are preserved on exit.
  * A1.L must point to a 64-byte buffer.
  *This trap is supported on Level 2 device drivers and should be called to find out whether the current device is Level 2 or not. If this trap succeeds all other filing system traps will be available.
  *The format of the information in the buffer is given below.
  *The number of allocation units needed to store a file is:
    * (file + header length +alloc unit size -1)/(alloc unit size).
===== Extended Information =====
^Mnemonic^Address^Length^Item^
|IOI_NAME|$00|String|Up to 20 characters medium name (null filled)|
|IOI_DNAM|$16|String|Up to 4 characters device name (eg WIN)|
|IOI_DNUM|$1C|Byte|Drive number|
|IOI_RDON|$1D|Byte|Non zero if read only|
|IOI_ALLC|$1E|Word|Allocation unit size (bytes)|
|IOI_TOTL|$20|Long|Total medium size (in allocation units)|
|IOI_FREE|$24|Long|Free space on medium (in allocation units}|
|IOI_HDRL|$28|Long|File header length (per file storage overhead)|
|IOI_FTYP|$2C|Byte|Format type (1=QDOS,2=MSDOS etc)|
|IOI_STYP|$2D|Byte|Format sub-type|
|IOI_DENS|$2E|Byte|Medium type (0=RAM,1=FLP,2=HD,3=CD)|
|IOI_REMV|$30|Byte|Set if removable|
|IOI_XXXX|$31|$0F bytes|Set to -1|

===== Example =====
The example below shows the use of this trap call. It is assumed that the channel ID is held at id(A6) and that buf(A6) is the address of a 64-byte buffer.

<code>
info    moveq   #iof_xinf,d0    ; $4F
        moveq   #-1,d3          ; Timeout
        moveq   #0,d1           ; D1 must be zero
        movea.l id(a6),a0       ; Set Channel ID
        lea     buf(a6),a1      ; Set address of 64 byte buffer        
        trap    #3              ; Get information
        tst.l   d0              ; OK? . .
        bne     error           ; . . no!
</code>