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- File : Talk
- Date : 21-Feb-97
- Author : © A.Thoukydides, 1996, 1997
- Description : ARMEdit messages supported by the !ARMEdit front-end.
-
-
- INTRODUCTION
-
- The !ARMEdit front-end supports several messages used by PC software. The
- messages are arranged in pairs: code running on the PC card send a message,
- and the front-end sends an acknowledgement (with the same reason code). No
- messages are sent from the front-end unrequested.
-
- All of the messages use the ID 256.
-
-
- MSG_ARMEDIT_FIND
-
- Check whether the front-end is running.
-
- Data sent:
-
- Offset Size Description
-
- 0 4 Reason code = &00000000.
-
- Data returned:
-
- Offset Size Description
-
- 0 4 Reason code = &00000000.
-
- The PC software sends this message to ID 256 to find the handle of the
- front-end software. A timeout should be used to detect whether the
- message has been delivered.
-
- All future messages should use the message handle.
-
-
- MSG_ARMEDIT_START
-
- Start an external edit.
-
- Data sent:
-
- Offset Size Description
-
- 0 4 Reason code = &00000001.
- 4 4 Byte offset of initial cursor position.
- 8 20 Null terminated DOS leaf name of file to edit.
- 28 256 Null terminated name of RISC OS file to edit.
-
- Data returned:
-
- Offset Size Description
-
- 0 4 Reason code = &00000001.
- 4 4 Handle for this edit.
-
- This message is used to start an external edit. The leaf name is used for
- display purposes - only the RISC OS name is used to access the file
- (which must exist when the message is sent).
-
- No status is returned by this message. Use MSG_ARMEDIT_POLL to check the
- state of the edit.
-
- A unique handle is returned for this file. This handle should be used
- when polling the status of the edit.
-
-
- MSG_ARMEDIT_POLL
-
- Poll the status of the external edit.
-
- Data sent:
-
- Offset Size Description
-
- 0 4 Reason code = &00000002.
- 4 4 Handle of edit to poll.
- 8 4 Flags:
- bit 0 Set to retrieve data.
- bit 1 Set to end external edit.
- bit 2 Set to mark file as safely saved.
-
- Data returned:
-
- Offset Size Description
-
- 0 4 Reason code = &00000002.
- 4 4 Flags:
- bit 0 Set if file modified since last poll.
- bit 1 Set if external edit aborted.
-
- This message is used to check or update the status of an external edit.
- The input flags allow the file to be retrieved from the editor, or to
- abandon the edit. It is also possible to mark the edit as safely saved
- after it has been saved by the editor.
-
- If a request has been made to retrieve a file then the returned flags
- should be checked until the modified flag is set.
-
- If the returned flags indicate that the edit has been aborted then no
- more messages should be sent for this edit.
-
-
- MSG_ARMEDIT_SAVEAS
-
- Display a Save As window for a specified file.
-
- Data sent:
-
- Offset Size Description
-
- 0 4 Reason code = &00000003.
- 4 256 Null terminated name of RISC OS file to save.
- 260 256 Null terminated suggested name of file to save.
-
- Data returned:
-
- Offset Size Description
-
- 0 4 Reason code = &00000003.
-
- Allow a file to be saved under a user specifiable name. This is intended
- for use by the PUTFILE command when no destination is specified. The
- file is deleted when it has either been saved, or when the user has
- cancelled the operation. No method for determining the success or
- failure of the operation is provided.
-
-
- THINGS TO DO
-
- The following are changes that may be made to the HPC services sometime in
- the future.
-
- Support execution of commands in a TaskWindow from the OSCLI command.
-
-
- VERSION HISTORY
-
- 0.00 (10-Sep-96) Original development version.
-
- 0.01 (05-Feb-97) Cursor position in external edits can be specified.
- Added Save As window support.
-
- 1.03 (21-Feb-97) First official release version.