Putting the Virtual Machine Boot Session in the Workplace Shell

See the example as shown in Figure "The Program Page of the Settings Notebook for a VMB".

The Session notebook allows the user to specify the session type and DOS Settings for the VMB session.

The difference between a VMB session and a "normal" VDM is that the DOS Settings value of DOS_STARTUP_DRIVE is set. This setting determines the location of the DOS kernel to be booted. By default, MVDM's DOS Emulation is loaded. However, the user may specify a location from which to load DOS, in which case the version of DOS residing at that location is loaded.

Figure "DOS Settings - DOS_STARTUP_DRIVE"

Example values for DOS startup drive are:

DOS Start up setting

Meaning
a:
Boot using the diskette in drive A:
c:\bootimg\dos50.vmb
Boot using the specified DOS image file
c:
Boot using the primary partition of the C: drive
The following restrictions apply:

A second diskette drive (B:) or hard disk (D:) cannot be specified as the startup drive.

To boot DOS from the C: partition, Boot Manager must be installed, and OS/2 Version 2.0 must reside in an extended partition on the first hard disk, or on another hard disk. See Booting from a DOS Partition.

Select the Save button to save the DOS settings and return.

Select the General notebook tab.

Change the Title field to your own name describing the new object.

Close the Settings notebook by double clicking on the system menu in the upper left corner of the window.

Other DOS Settings

DOS settings which control the VDM hardware environment are applicable to the VMB session and operate in the same way as for a DOS Emulation windowed or full-screen session. Those which modify the virtual DOS environment are ignored; the equivalent settings are instead determined by the CONFIG.SYS file of the booted DOS kernel. Ignored settings include:

DOS_DEVICES

DOS_UMB

DOS_SHELL

DOS_HIGH

DOS_LASTDRIVE

DOS_VERSION

The FCB limit is the lesser of either the booted DOS, or OS/2 Version 2.0 CONFIG.SYS value. The VMB session will by default have 640KB of real memory, mou se support, 2MB Expanded (EMS) memory, 2MB DPMI, and 2MB XMS memory.

Booting from an OS/2 V2.0 Program

By using DosStartSession it is possible to start a VMB session from an OS/2 V2.0 program. For more details see the following sample which shows how to boot from the disk drive A:. Of course, by changing startd.Environment, this sample can also be used to start a VMB from another hard disk partition or a boot image file from your hard disk.

Figure "VMB from an OS/2 2.0 Program"