Prosody generic: API: sm_channel_alloc_placed

Prototype Definition

int sm_channel_alloc_placed(struct sm_channel_alloc_placed_parms *channelp)

Parameters

*channelp
a structure of the following type: 
typedef struct sm_channel_alloc_placed_parms {
	tSMChannelId channel;					/* out */
	enum kSMChannelType {
		kSMChannelTypeInput,
		kSMChannelTypeOutput,
		kSMChannelTypeHalfDuplex,
		kSMChannelTypeFullDuplex,
	} type;							/* in */
	tSMModuleId module;					/* in */
	tSM_INT caps_mask;					/* in */
} SM_CHANNEL_ALLOC_PLACED_PARMS;

Description

Allocates, on a specific module, a new channel to generate output data and/or process input data. The type parameter determines which kind of channel is allocated

If the call completes successfully, the parameter channel will be set to the identifier for that channel.

The task of supporting this channel is assigned by the driver to the module specified by the module parameter.

The caps_mask parameter is ignored.

Fields

channel
The allocated channel.
type
The type of channel to allocate. One of these values:
kSMChannelTypeInput
An input channel, which can be used to record data, recognise digits and tones etc.
kSMChannelTypeOutput
An output channel, which can be used to replay data, generate tones, dial DTMF digits etc.
kSMChannelTypeHalfDuplex
A channel that may operate either in input mode or in output mode (but not both simultaneously, except for DTMF detection). Resources required by a channel are allocated only as soon as they are needed, so there is no advantage in using a half-duplex channel over a full-duplex channel, and since it is typically more complicated for an application to handle half-duplex channels than full-duplex channels, it is recommended that full-duplex channels always be used in preference to half-duplex channels.
kSMChannelTypeFullDuplex
A channel that may operate both in input mode and in output mode (simultaneous input and output possible).
module
A value obtained from sm_open_module() which indicates the module where the channel is to be allocated.
caps_mask
Bitmask of required capabilities, or zero to indicate that the default capabilities are required. This field is ignored.

Returns

0 if call completed successfully, otherwise a standard error such as:

This function is part of the Prosody generic API.