Intel 05-2409-003 사용자 설명서

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This chapter provides some tips when developing programs using Global Call. Topics include: 

The following tips apply when programming with Global Call: 

When using Global Call functions, the application must use the Global Call handles (that is, 
the line device ID and CRN) to access Global Call functions. Do not substitute a network, 
voice or media device handle for the Global Call line device ID or CRN. If the application 
needs to use a network, voice or media device handle for a specific network or voice library 
call, for example, nr_scroute( ) (for E1, T1 or ISDN technologies only) or dx_play( ) (all 
technologies), you must use the gc_GetResourceH( ) to retrieve the network, voice or media 
device handle, associated with the specified Global Call line device. The gc_GetResourceH( ) 
function is only needed if the voice or media resource is associated with a Global Call line 
device. If a voice resource is not part of the Global Call line device, the device handle returned 
from the dx_open( ) call should be used. 

Do not access the underlying call control libraries directly. All access must be done using the 
Global Call library, that is, using Global Call (gc_) functions. 

Do not call any network library (dt_) function directly from your application that may affect 
the state of the line or the reporting of events, for example, dt_settssig( ), dt_setevtmsk( ), or 
others. 

The GCEV_BLOCKED and the GCEV_UNBLOCKED events are line related events, not call 
related events. These events do not cause the state of a call to change. 

Before exiting an application: 

Drop and release all active calls, using the gc_DropCall( ) and gc_ReleaseCallEx( ) 
functions. 

Close all open line devices, using the gc_Close( ) function. 

Stop the application, using the gc_Stop( ) function 

Before issuing gc_DropCall( ), you must use the dx_stopch( ) function to terminate any 
application-initiated voice functions, such as dx_play( ) or dx_record( ). 

In Windows environments, although asynchronous models are more complex than the 
synchronous model, asynchronous programming is recommended for more complex 
applications that require coordinating multiple tasks. Asynchronous programming can handle 
multiple channels in a single thread. In contrast, synchronous programming requires separate