文件包中有三个文件：sound.c,mixer.c.vol.c

其中sound.c是实现打开、关闭音频接口，同时实现录音放音功能的文件；

mixer.c是实现读取当前混音器的设备信息，设置左、右声道增益功能的文件；

vol.c是实现调节音量功能的文件

此文件是基于linux开发板编写的-Package has three files: sound.c, mixer.c.vol.c sound.c which is to achieve open, close the audio interface, simultaneous recording playback function in the file　mixer.c read the current mixer to achieve the device information, setting the left and right channel gain function file　vol.c adjust the volume function is to achieve a document This document is prepared based on linux development board