AuCreatePlay(3X)

NAME

AuCreatePlay − create an audio play widget

SYNOPSIS

extern Widget
AuCreatePlay (

Widget parent,

String ∗ name,

ArgList ∗ arglist,

Cardinal argcount);

DESCRIPTION

AuCreatePlay() creates a play widget.

If you use the streams facility, the toolkit creates a file descriptor in connectFd during AuInvokePlay(). After calling AuInvokePlay(), retrieve the file descriptor by calling XtSetArg(args[0], AuNconnectFd, &stream_fd); and then call XtGetValue(playWidget,args,1);. Then, use the OS select, read, and write calls.

After calling AStopAudio() to stop the transaction, the application program must retrieve all the data in the buffer and close the file descriptor. A callback routine for AuNStopped may include all of these operations.

Note that for a play streams operation to work, a callback routine for AuNdataNeeded must be added using AtAddCallback().

To enable an application to use a widget after it is created, bind the widget library with the application as follows: ld my_file.o... -lAt -lAlib

parent Name of the parent widget

name Name for this widget

arglist The argument list for the widget

argcount The number of arguments in arglist.

arglist may contain the following:

gain Volume, in per cent of total gain. Acceptable values are from 0 to 100. Default is 70.

fileFormat Audio file format. Acceptable values are:

AuFMulaw AuFAlaw

AuFLinear16 AuFSun

AuFLinear8 AuFRiff

AuFMac AuFLinear8Offset

AuFUnknown

Default is AuFUnknown.

dataFormat Audio data format. Acceptable values are:

AuDMulaw AuDAlaw

AuDLinear16 AuDLinear8

AuDLinear8Offset AuDUnknown

Default is AuDUnknown.

durationType Duration units. Acceptable values are:

AuSamples AuMilliseconds

AuFullLength

Default is AuFullLength.

duration Number of units to play. Acceptable values are -1 to max_int. Default is ~0 (-1, play until notified).

fileName Name of the file to play (must be set prior to invocation of the play widget.) There is no default value.

startTimeType Type of start time unit. Acceptable values are AuSamples and AuMilliseconds. Default is AuMilliseconds.

startTime Number of units into the file to begin recording. Acceptable values are 0 to max_int. Default value is 0 (BOF).

pause Start in paused state. Acceptable values are ON or OFF. Default is OFF.

stop Stop mode. Acceptable values are:

AuStopLinkTrans AuStopThisTrans

AuStopEndLoopTrans AuStopNone

Default is AuStopNone.

audioConnection Pointer to Audio structure for this connection, returned by AOpenAudio(). Specifying a valid pointer for this argument is mandatory; the default value is NULL, which will cause the program to fail.

streamOrFile Source of audio data. Acceptable values are AuStream or AuFile. Default is AuFile.

sStream Pointer to SStream structure for this AuStream-type widget. Specifying a valid pointer for this argument is mandatory; the default value is NULL, which will cause the program to fail.

connectFd File descriptor of the non-blocking connection made for the stream by the toolkit; created during AuInvokeRecord().

reserved

writeMode Mode for saving data. Acceptable values are:

AuOverWrite AuTruncAppend

AuInsert

Default is AuOverWrite.

speaker Speaker choice. Acceptable values are AuInternal or AuExternal. Default is AuInternal.

link name of another play widget; when link is finished playing, the current widget starts immediately and automatically. Default is NULL.

The link feature enables two or more play widgets to be linked into a continuous play operation. Follow these steps to link two or more widets:

1. Create widget A with pause ON and with NULL specified in link.

2. Create widget B with pause ON and with A’s name specified in link.

3. Repeat step 2 for as many widgets as you want in the chain (creating C with B’s name in link, and so on.)

4. Invoke widget A.

loopCount Number of times to play this widget. Acceptable values are -1 to max_int. Default is 0. Note that a value of -1 specifies an infinite loop.

priority Priority level of play request. Acceptable values are:

AuUrgent AuHigh

AuNormal AuLow

Default is AuNormal.

RETURN VALUE

Upon successful completion, AuCreatePlay() returns the widget ID.

ERRORS

AuCreatePlay() does not return an error status.

DEPENDENCIES

This function belongs to the Audio Application Program Interface widget library. The audio server must run on a system that has audio hardware. To find out whether or not your system has audio hardware, refer to the hardware manual that accompanies your system.

AUTHOR

AuCreatePlay() was developed by HP.

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