ComDBClaimPort function

ComDBClaimPort logs an unused COM port number as "in use" in the COM port database.

Syntax

LONG ComDBClaimPort(
  HCOMDB HComDB,
  DWORD  ComNumber,
  BOOL   ForceClaim,
  PBOOL  Forced
);

Parameters

HComDB

Handle to the COM port database that is returned by ComDBOpen.

ComNumber

Specifies which COM port number the caller attempts to claim. A port number is an integer that can range from 1 to COMDB_MAX_PORTS_ARBITRATED.

ForceClaim

Reserved for internal use only.

Forced

Reserved for internal use only.

Return Value

ComDBClaimPort returns one of the following status values.

Return code Description
ERROR_SUCCESS
The COM port number was not in use and is now logged as "in use".
ERROR_CANTWRITE
The routine could not write to the database.
ERROR_INVALID_PARAMETER
One of the following is true: The specified handle to the COM port database is not valid. The specified port number is greater than COMDB_MAX_PORTS_ARBITRATED.
ERROR_NOT_CONNECTED
The routine could not access the database. To get extended error information, call GetLastError.
ERROR_SHARING_VIOLATION
The specified port number is already in use.
ERROR_Xxx
An internal error occurred; call GetLastError to get extended error information.

Remarks

Claiming a COM port number in the COM port database logs the port number as "in use". Note that the database does not contain information about the caller or device that claims a port number.

ComDBClaimPort runs in user mode.

For more information, see Obtaining and Releasing a COM Port Number.

Requirements

   
Target Platform Desktop
Header msports.h (include Msports.h)
Library Msports.lib
DLL Msports.dll

See Also

ComDBClaimNextFreePort

ComDBReleasePort