linux 如何获取系统音量修改系统音量

来源：互联网发布：网络语言9代表什么意思编辑：程序博客网时间：2024/06/06 00:39

这几天一直在查资料如何在linux下获取系统音量并修改音量，找了很多资料终于还是在csdn论坛里找到了答案。

#include <stdio.h>#include <alsa/asoundlib.h>int main(void){    int unmute, chn;    int al, ar;    snd_mixer_t *mixer;    snd_mixer_elem_t *master_element;        snd_mixer_open(&mixer, 0);    snd_mixer_attach(mixer, "default");    snd_mixer_selem_register(mixer, NULL, NULL);    snd_mixer_load(mixer);  /* 取得第一個 element，也就是 Master */    master_element = snd_mixer_first_elem(mixer);  /* 設定音量的範圍 0 ~ 100 */      snd_mixer_selem_set_playback_volume_range(master_element, 0, 100);  /* 取得 Master 是否靜音 */      snd_mixer_selem_get_playback_switch(master_element, 0, &unmute);      if (unmute)            printf("Master is Unmute.\n");      else            printf("Master is Mute.\n");  /* 取得左右聲道的音量 */      snd_mixer_selem_get_playback_volume(master_element, SND_MIXER_SCHN_FRONT_LEFT, &al);      snd_mixer_selem_get_playback_volume(master_element, SND_MIXER_SCHN_FRONT_RIGHT, &ar);  /* 兩聲道相加除以二求平均音量 */      printf("Master volume is %d\n", (al + ar) >> 1);  /* 設定 Master 音量 */      snd_mixer_selem_set_playback_volume(master_element, SND_MIXER_SCHN_FRONT_LEFT, 99);      snd_mixer_selem_set_playback_volume(master_element, SND_MIXER_SCHN_FRONT_RIGHT, 99);  /* 將 Master 切換為靜音 */      for (chn=0;chn<=SND_MIXER_SCHN_LAST;chn++) {            snd_mixer_selem_set_playback_switch(master_element, chn, 0);      }  /* 將 Master 切換為非靜音 */      for (chn=0;chn<=SND_MIXER_SCHN_LAST;chn++) {            snd_mixer_selem_set_playback_switch(master_element, chn, 1);      }  return 0;}

最后在编译的时候要记得添加libasound.so库