5B ReadScratchFile¶

Stub MON 5B (5 decimal) · Mnemonic RDISK · Group: File Operations (manual section 2.4)

Available from: Background programs (manual compatibility box)

Emulation source: src/handlers/mon_5B_ReadScratchFile.c

Description¶

Reads randomly from the scratch file. One block is transferred. There is one scratch file connected to each terminal. It is opened for random read and write access when you log in. Its file number is 100B.

Notes¶

The standard block size is 512 bytes. You can change this with SetBlockSize. The first block is number 0.

Parameters¶

Name	Type	Direction	Description
`BlockNumber`	INTEGER	In	Block number to start reading from. First block is 0.
`DataDestination`	ARRAY	Out	Buffer address for the transferred data (256 words / 512 bytes).

Direction: In = the program supplies the value, Out = the call returns it, In/Out = both.

Compatibility¶

Machines	Users	Programs
ND-100	All users	Background programs

The manual's compatibility box for this call, word for word.

Yes/no fields from the YAML extraction (not in the manual's words):

ND-100	ND-500	User programs	RT programs	System programs
No	No	Yes	Yes	No

Disagreement

The manual box says ND-100, but the yes/no fields say ND-100 = No, ND-500 = No. The manual box is the source.

Examples¶

From the manual (OCR text, not corrected).

PLANCFORTRANPascalCOBOLMAC

INTEGER : BlockNumber
BYTES : DataDestination(0:511)
...
ON ROUTINEERROR DO
    IF ErrCode > 0 THEN ...
ENDON
Monitor_Call('ReadScratchFile', BlockNumber, DataDestination(0))

INTEGER BlockNumber
INTEGER DataDestination(256)
...
Monitor_Call('ReadScratchFile', BlockNumber, DataDestination(1))
IF (ErrCode .NE. 0) THEN ...

BlockNumber : INTEGER2;
DataDestination : RECORD...END;
...
ReadScratchFile(BlockNumber, DataDestination);
IF ErrCode <> 0 THEN ...

01 BlockNumber COMP.
01 DataDestination.
   02 array COMP OCCURS 256 TIMES.
01 ErrCode COMP.
...
MONITOR-CALL "ReadScratchFile" USING BlockNumber, DataDestination.
CALL "CbError" USING ErrCode.
IF ErrCode NOT = 0 GO ...

| Instruction | Description                                  |
|-------------|----------------------------------------------|
| LDT BLKNO   | %Block number to be read.                    |
| LDX (BUFF   | %Address of buffer to receive block read.    |
| MON 5       | %Monitor call ReadScratchFile.               |
| JMP ERROR   | %Error return from monitor call.             |
| ...         | %Normal return.                              |
| ERROR, ...  | %Error number in register A.                 |
| BLKNO, ...  |                                              |
| BUFF, 0     | `*+400/` %Make a buffer of 256 words, 1 block. |

ndmonlib implementation¶

Stub Registered MON_STATUS_NOT_IMPLEMENTED: the handler is a stub. mon_dispatch() in src/core/mon_dispatch.c reports the call as unimplemented without calling it.


Handler	`mon_5B_ReadScratchFile`
Code lines	6 (non-blank, non-comment lines in the file)

Source¶

SINTRAN III Monitor Calls (ND-860228.2 EN), page 403.