OS_Dor, The DOR interface
- Gunther Strube
- Elpekos
Owned by Gunther Strube
Register parameters
RST 20H, DEFB $87
IN:
A = reason code
HL, IX arguments
Reason codes are as follows:
DR_GET ($01) get handle for a DOR name (internal use)
DR_DUP ($02) duplicate DOR
DR_SIB ($03) return brother DOR
DR_SON ($04) return child DOR
DR_FRE ($05) free DOR handle
DR_CRE ($06) create blank DOR
DR_DEL ($07) delete DOR
DR_INS ($08) insert DOR
DR_RD ($09) read DOR record
DR_WR ($0A) write DOR record
DR_OP ($0B) open explicit filename (OZ 5.0 and newer)
DR_USE ($0C) handle in use (OZ 5.0 and newer)
OUT, if call successful:
Fc = 0
returned values depend on A(in)
OUT, if call failed:
Fc = 1
A = error code:
RC_HAND ($08), bad handle
RC_BAD ($04), bad argument
RC_ROOM ($07), no room
RC_EOF ($09), end of file
Registers changed after return:
not documented.Â
Notes
When the last DOR record in a list has been read, an RC_EOF is reported and the handle is immediatly released, ie. it will not be necessary to release the handle with a DR_FRE call.
Bugs
Corrupts the stack pointer SP when called with an old handle, e.g. when a previous DR_ call resulted in a "End of list" error (RC_EOF).
Reason code specifications
DR_GET ($01), get a handle for a DOR name (internal usage)
 IN: -
OUT, if call successful:
Fc = 0
IX = DOR handle
A = minor type (device, always)
Registers changed after return:
..BCDEHL/..IY same
AF....../IX.. different
Note
- Operating system only. Do not use this call.
- Instead use OS_Dor / DR_OP or GN_Opf / OP_DOR to obtain a DOR handle.
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DR_DUP ($02), duplicate DOR
IN:
IX = DOR handle
OUT, if call successful:
Fc = 0
BC = duplicate DOR handle (IX is still valid)
OUT, if call failed:
Fc = 1
BC = 0 (IX is still valid)
A = error code
RC_HAND ($08), bad DOR handle
Registers changed after return:
....DEHL/IXIY same
AFBC..../.... different
DR_SIB ($03), return brother DOR
IN:
IX = DOR handle
OUT, if call successful:
Fc = 0
IX = next DOR handle (original IX invalid)
A = minor type
OUT, if call failed:
Fc = 1
A = error code
RC_HAND ($08), bad DOR handle
Registers changed after return:
..BCDEHL/..IY same
AF....../IX.. different
DR_SON ($04), return child DOR
IN:
IX = DOR handle
OUT, if call successful:
Fc = 0
IX = child DOR handle (original IX invalid)
A = minor type
OUT, if call failed:
Fc = 1
A = error code
RC_HAND ($08), bad DOR handle
Registers changed after return:
..BCDEHL/..IY same
AF....../IX.. different
DR_FRE ($05), free DOR handle
IN:
IX = DOR handle
OUT, if call successful:
Fc = 0
IX = 0
OUT, if call failed:
Fc = 1
A = error code
RC_HAND ($08), bad DOR handle
Registers changed after return:
..BCDEHL/..IY same
AF....../IX.. different
DR_CRE ($06), create blank DOR
IN:
IX = parent DOR handle
B = minor type
OUT, if call successful:
Fc = 0
IX = new DOR handle (original IX invalid)
OUT, if call failed:
Fc = 1
A = error code
RC_HAND ($08), bad DOR handle
RC_BAD ($04), bad argument
RC_ROOM ($07), no room
Registers changed after return:
..BCDEHL/..IY same
AF....../IX.. different
DR_DEL ($07), delete DOR
IN:
IX = DOR handle
OUT, if call successful:
Fc = 0, DOR deleted
IX = 0
OUT, if call failed:
Fc = 1
A = error code
RC_HAND ($08), bad DOR handle
Registers changed after return:
..BCDEHL/..IY same
AF....../IX.. different
Note
This call deletes a DOR node and deallocates its memory used by filesystem (DN_Fil minor type only)
DR_INS ($08), insert DOR
IN:
BC = parent DOR handle
IX = DOR handle
OUT, if call successful:
Fc = 0
original BC and IX DOR handles are still valid
OUT, if call failed:
Fc = 1
BC and IX is still valid
A = error code
RC_HAND ($08), bad DOR handle
Registers changed after return:
..BCDEHL/IXIY same
AF....../.... different
DR_RD ($09), read DOR record
IN:
B = record type
C = buffer length
DE = user buffer address (to store information of read, always local, in S0 or S1)
IX = DOR handle
OUT, if call successful:
Fc = 0
original IX DOR handle is still valid
C = actual length of information
OUT, if call failed:
Fc = 1
original IX is still valid
A = error code
RC_HAND ($08), bad DOR handle
RC_BAD ($04), bad argument
RC_FAIL ($16), information is not present
Registers changed after return:
..B.DEHL/IXIY same
AF.C..../.... different
DR_WR ($0A), read DOR record
IN:
B = record type
C = buffer length
DE = user buffer address (to store information to be written, always local, in S0 or S1)
IX = DOR handle
OUT, if call successful:
Fc = 0
original IX DOR handle is still valid
C = length of information written
OUT, if call failed:
Fc = 1
original IX is still valid
A = error code
RC_HAND ($08), bad DOR handle
RC_BAD ($04), bad argument
RC_FAIL ($16), information is not present
Registers changed after return:
..B.DEHL/IXIY same
AF.C..../.... different
DR_OP ($0B), open explicit filename (OZ 5.0 and newer)
IN:
C = number of segment to parse (0 for all, default)
DE = filename buffer (always local, in S0 or S1)
OUT, if call successful:
Fc = 0
IX = handle (device type, always)
A = DOR type (device, file, directory, EPROM)
B = segment count in explicit filename
HL = last character parsed in filename (separator or null terminator)
OUT, if call failed:
Fc = 1
A = RC_Fail, buffer not in S0 or S1
A = RC_Onf, filename does not exist
Registers changed after return:
...CDE.. / ..IY same
AFB...HL / IX.. different
Notes
- This call is the optimized equivalent of GN_Opf / OP_DOR. It is used by GN_Opf itself and allows a faster file open.
- It is recommended to use this call before making file DOR operation like reading filename, timestamp...
- It always create a device type handle ($01) which is required to perform DOR header operation. Type can be changed by calling OS_Fn / FN_CH (in order to perform file I/O).
- API call implemented in OZ 5.0
DR_USE ($0C), handle in use (OZ 5.0 and newer)
IN:
IX = DOR handle
OUT, if call successful:
Fc = 0, handle or device is NOT already in use
OUT, if call failed:
Fc = 1, original IX is still valid
A = error code
RC_USE, already in use
Registers changed after return:
..BCDEHL/IXIY same
.F....../.... different