每次拔下耳机时（就像电话一样），是否可以从计算机中使声音静音，以停止声音然后在扬声器中播放？

如何检测拔出

基本上对我有用的是：

# When plugged in:
cat /proc/asound/card0/codec#0 > pluggedin.txt

# When not plugged in:
cat /proc/asound/card0/codec#0 > notplugged.txt

# Then compare the differences
diff pluggedin.txt notplugged.txt

对我来说，区别在于“ Amp-Out vals”下的“ Node 0x16”：

Node 0x16 [Pin Complex] wcaps 0x40058d: Stereo Amp-Out             Node 0x16 [PinComplex] wcaps 0x40058d: Stereo Amp-Out
  Amp-Out caps: ofs=0x00, nsteps=0x00, stepsize=0x00, mute=1         Amp-Out caps:ofs=0x00, nsteps=0x00, stepsize=0x00, mute=1
  Amp-Out vals:  [0x80 0x80]                                    |    Amp-Out vals:  [0x00 0x00]

因此，我根据发现的差异进行检测。

如何静音

有了这些知识，您就可以在后台运行脚本了。如果将其拔出，脚本将使扬声器静音，就像使用一样amixer sset Master playback 0%（或其他任何命令）。

#!/bin/bash
# This scripts detecs unplugging headphones.

oldstatus="unrelated string"
while [ 1 ]; do
    # The following line has to be changed depending on the difference (use diff) in '/proc/asound/card0/code#0'
    status=$(grep -A 4 'Node 0x16' '/proc/asound/card0/codec#0' |  grep 'Amp-Out vals:  \[0x80 0x80\]')
    if [ "$status" != "$oldstatus" ]; then
        if [ -n "$status" ]; then
            echo "Plugged in"
             amixer sset Master playback 80% # Set volume to 80%
            oldstatus="$status"
        else
            echo "Unplugged"
            amixer sset Master playback 0%  # Mute
            oldstatus="$status"
        fi
    fi
done

您可以使其可执行chmod +x scriptname.sh并放入启动应用程序。您必须通过找到自己的差异来调整拔出检测/proc/asound/card0/codec#0（甚至可以更改多个声卡的数字）。

相关链接：

https://wiki.ubuntu.com/Audio/PreciseJackDetectionTesting

/unix/25776/detecting-headphone-connection-disconnection-in-linux

拔/插耳机时如何自动改变音量？

这在Ubuntu 14.04上对我有用：

“使耳机熄灭，使其静音。插入耳机并提高音量。取下耳机并检查是否静音。”

图片来源：RevDrStrangelove，网址为https://www.reddit.com/r/LifeProTips/comments/369k76/lpt_request_automaticly_mute_laptop_after_headset/

对于ubuntu-16.10，我在此答案中所做的更改很少。

oldresult="Some Random String"

while [ 1 ]; do
        # incase of plugged out result will contain some data
        result=$(grep "EAPD 0x2: EAPD" /proc/asound/card0/codec#0)

        # checking for oldresult if not same then only go inside
        if [ "$oldresult" != "$result" ]; then
                oldresult=$result
                if [[ -z "$result" ]]; then
                        notify-send "Plugged In"
                        amixer sset Master playback 80% # Set volume to 80%
                 else
                        notify-send "Plugged Out"
                        amixer sset Master playback 0% # Set volume to 0%
                 fi
        fi
done

如果您有与事件问题在追赶/etc/acpi/handler.sh看到我的答案。它也没有设备代码为Node 0x16。