linux 录音放音程序（从网上找来的）

/*
  Name: SndKit.c
  Copyright: GPLv2
  Author: rockins(ybc2084@163.com)
  Date: 15-10-06 18:22
  Description: implent raw sound record/play
  run: ./SndKit [-h] [-d device] [-c channel] [-b bits] [-f hz] [-l len] <-r|-p file>
  e.g.:
  ./SndKit -h     show help information
  ./SndKit -r record.wav                   record audio from microphone(/dev/dsp)
  ./SndKit -d /dev/dsp -p record.wav        playback record.wav via /dev/dsp
  ./SndKit -b 8 -f 22 -r reacord.wav        record audio in 8 bit & 22k hz
  ./SndKit -d /dev/dsp -c 2 -r record.wav   record audio in /dev/dsp and stereo
  ./SndKit -r -l 40 record.wav   record 40k audio data
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <linux/soundcard.h> /*for OSS style sound programing */
#define TRUE  1
#define FALSE  0
#define FMT8BITS AFMT_U8 /*unsigned 8 bits(for almost PC) */
#define FMT16BITS AFMT_S16_LE /*signed 16 bits,little endian */
#define FMT8K    8000 /*default sampling rate */
#define FMT11K   11025 /*11,22,44,48 are three pop rate */
#define FMT22K   22050
#define FMT44K   44100
#define FMT48K  48000
#define MONO     1
#define STEREO   2
#define ACT_RECORD 0
#define ACT_PLAY 1
#define DFT_SND_DEV  "/dev/dsp"
#define DFT_SND_FMT  FMT8BITS
#define DFT_SND_SPD  FMT8K
#define DFT_SND_CHN  MONO
#define DFT_LEN  1024 /*default record length:40k */
#define BUFF_SIZE  512 /*buffer size:512 Bytes */
/************** function prototype ********************/
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