DEFAULT monitor command

V+ Operating System Reference Guide

DEFAULT monitor command

Syntax

DEFAULT physical_device>unit: directory_path

Function

Define the default relationship between a V+ logical device and the physical device to be accessed. Also, display the current default.

Parameters

physical_device
Optional name of the physical device to be associated with the logical device. Acceptable device names are "DISK", "KERMIT", "NFS" and "SERIAL:n", which must be specified without quotes, and can be abbreviated to "DI", "K", "N" or "SE:n").

The ">" character must be omitted if the physical device is omitted, in which case, the previous default physical device is not changed.

unit
Optional string specifying the desired default unit. For normal V+ disk assignments, this parameter is the letter name of the disk drive of interest-"A" or "C" (specified without quotes). For the Kermit physical device, this string can be any sequence of characters not containing a colon (":"). For the NFS device, this is the name of a remotely mounted server disk, specified by the FSET/MOUNT attribute.

The ":" character must not be entered if the unit is not specified. In that case, the previous default unit is not changed (except as noted above).

directory_path
Optional string specifying the directory path of interest. Normally, this parameter will contain file names and backslash (\) characters. (For disk devices, V+adds a "\" if one is not included at the end of a path specification.)

When the current or specified "physical_device" is not a disk device, a leading "\" specifies that the directory path starts at the top-level directory. That is, the path replaces any default path currently defined (absolute path). The absence of a leading "\" indicates that the path is to be appended to the current default path (relative path).

NOTE: If "unit" and "directory_path" are omitted, the unit and the directory path will be canceled in the default. If all parameters are omitted, the current directory path is displayed.

If the "unit" parameter specifies a unit different from the current default, the directory path specified is always started at the top-level directory.

As a special case, nonstandard directories (for example,
"[ ... ]" or "/.../") are accepted to assist with referencing other systems via Kermit.

Details

In the following description, the term "directory specification" is used to refer to the combination of physical device and/or disk unit and/or directory path.

When a disk-related V+ operation (for example, FDIRECTORY, LOAD, STORE, and FOPEN_) is processed, the V+ system automatically combines the current "default" directory specification with the directory specification supplied to the command or instruction. The DEFAULT command can be used to set the directory specification that is to be used in such situations. (See the examples below.)

NOTE: The DEFAULT command does not verify that the specified default device, unit, and directory can be accessed.

The DEFAULT command can be entered without any parameters to have the current default directory specification displayed on the monitor screen.

When the V+ system is booted from disk, the initial default disk relationship is set according to the configuration stored on the system disk.1

After a DEFAULT command is processed, subsequent disk operations (and DEFAULT commands) will use the new default directory specification as required. The following "rules" determine the directory specification that will result from a combination of the default specification and the directory specification in any command or instruction:

If no unit is specified, the unit in the default unit will be used. Any directory path specified is appended to the default directory path if the specified path does not start with a backslash (\). Otherwise, the default directory path is ignored.

(As noted above, however, the DEFAULT command cancels both the default unit and directory path if both the unit and directory path are omitted.)

If the unit specified is the same as the current default unit, the specified directory path (if any) is appended to the default directory path if the specified path does not start with a backslash (\). Otherwise, the default directory path is ignored.

If the unit specified is different from the current default unit, any directory path specified is always started at the top-level directory of the specified unit. (That is, the default directory path is ignored.)

See the V+ Operating System User's Guide for additional details on directory specifications, including how to specify the "directory_path" parameter.

Examples

The following examples illustrate how the DEFAULT command can be used to display or set the default directory specification.

DEFAULT Displays the current default for DISK.

DEFAULT = A:
Changes the default disk drive to unit "A".

DEFAULT = DI>C:\ROB1
Changes the default subdirectory to be the subdirectory "ROB1" on disk unit "C", on the physical device "DISK".

DEFAULT = TEST\DEMO
When used after the previous command, this changes the default directory path to "\ROB1\TEST\DEMO\" (on disk unit "C").

DEFAULT = K>
Changes the default disk physical device to be the KERMIT serial line. The default unit and directory path are both canceled.

The following examples show how the default directory specification is applied in certain situations. In each case, the current default directory specification is assumed to be "DISK>C:\ROB1\".

Command as entered by user: FDIRECTORY *.V2
Command as processed: FDIRECTORY DISK>C:\ROB1\*.V2

Comment: Whole default directory specification used.

Command as entered by user: FDIRECTORY JOB1\FEED*.*
Command as processed: FDIRECTORY DISK>C:\ROB1\JOB1\FEED*.*

Comment: Device, disk, and root directory are taken from the default directory specification.

Related Keywords

CD monitor command

$DEFAULT string function

FSET monitor command

FSET program instruction

1 Adept delivers V+ system boot disks with the default disk unit set to "DISK>D". The default unit and directory path can be changed with the CONFIG_C utility. See the manual Instructions for Adept Utility Programs for details.

DEFAULT	Displays the current default for DISK.
DEFAULT = A:	Changes the default disk drive to unit "A".
DEFAULT = DI>C:\ROB1	Changes the default subdirectory to be the subdirectory "ROB1" on disk unit "C", on the physical device "DISK".
DEFAULT = TEST\DEMO	When used after the previous command, this changes the default directory path to "\ROB1\TEST\DEMO\" (on disk unit "C").
DEFAULT = K>	Changes the default disk physical device to be the KERMIT serial line. The default unit and directory path are both canceled.