function closes the specified open line device.
A handle to the open line device to be closed. After the line has been
successfully closed, this handle is no longer valid.
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.
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.
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.
- Software for developers
Software for Android Developers
- More information resources
Unix Manual Pages