|
lineClose
The lineClose function closes the specified open line device.
LONG lineClose(
Parameters
hLine
A handle to the open line device to be closed. After the line has been
successfully closed, this handle is no longer valid.
Return Values
Returns zero if the request is successful or a negative error number if an
error has occurred. Possible return values are:
LINEERR_INVALLINEHANDLE, LINEERR_RESOURCEUNAVAIL, LINEERR_NOMEM,
LINEERR_UNINITIALIZED, LINEERR_OPERATIONFAILED, LINEERR_OPERATIONUNAVAIL.
Remarks
If an application calls lineClose while it still has active calls on the opened line, the application's
ownership of these calls is revoked. If the application was the sole owner of these
calls, the calls are dropped as well. It is good programming practice for an
application to dispose of the calls it owns on an opened line by explicitly
relinquishing ownership and/or by dropping these calls prior to closing the line.
If the close was successful, a LINE_LINEDEVSTATE message is sent to all applications that are monitoring the line status of
open/close changes. Outstanding asynchronous replies are suppressed.
Service providers may find it useful or necessary to forcibly reclaim line
devices from an application that has the line open. This may be useful to prevent
a misbehaved application from monopolizing the line device for too long. If
this happens, a LINE_CLOSE message is sent to the application, specifying the line
handle of the line device that was closed.
The lineOpen function allocates resources to the invoking application, and applications
may be prevented from opening a line if resources are unavailable. Therefore, an
application that only occasionally uses a line device (such as for making
outbound calls) should close the line to free resources and allow other applications
to open the line.
See Also
LINE_CLOSE, LINE_LINEDEVSTATE, lineOpen
Related Links
Software for Delphi and C++ Builder developers
Software for Visual Studio .NET developers
Software for Visual Basic 6 developers
Delphi Tips&Tricks
MegaDetailed.NET
More Online Helps
Win32 Programmer's Reference (win32.hlp)
Win32 Multimedia Programmer's Reference (mmedia.hlp)
OLE Programmer's Reference (ole.hlp)
Microsoft Windows Pen API Programmer's Reference (penapi.hlp)
Microsoft Windows Sockets 2 Reference (sock2.hlp)
Unix Manual Pages
|