Communications
The following settings control the communications environment (COM ports)
used by a VDM.
COM_HOLD
Function:
When set on, provides exclusive
access to COM ports for the specified VDM, preventing other processes from
using the port and preventing the operating system from releasing the port
until the VDM terminates.
Advantages:
For
certain applications which use COM ports and which require multiple programs
to access the COM port (for example, this setting prevents the COM port
from being released when the first program terminates).
Drawbacks:
If not required by the application running
in a VDM, this setting may prevent other applications from accessing COM
ports.
Default:
Settable:
Examples:
Certain
bulletin board applications use one program to dial the BBS and another
to exchange information; setting COM_HOLD on prevents the operating system
from releasing the COM port when the first program terminates.
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