[SOLVED] how do I extract the mixer volume?

madeye · 2010-01-26 19:44:55

I'm setting up openbox to use my media keys, and want to show an OSD with the current volume(%) when I press volume up or down.
I have come this far:

amixer get Master |grep % |awk '{print $4}'|sed 's/.//'

this gives me

51%]

How do I get rid of the last bracket?

Is there an easier way to get this value? (probably. I don't often do something like this )

Through google I found how to remove the first char, and I also found how to remove the last char using sed. However I couldn't find anything that combines the two.

Any good ideas?

Last edited by madeye (2010-01-26 20:54:58)

Grazz256 · 2010-01-26 20:11:56

amixer get Master |grep % |awk '{print $5}'|sed -e 's/\[//' -e 's/\]//'

Probably not good form, but it works
Note that I have to change $4 to $5 for it to work on my machine

Cheers

edit
a slightly nicer version..
amixer get Master |grep % |awk '{print $5}'|sed 's/[^0-9\%]//g'

or if you dont want the %
amixer get Master |grep % |awk '{print $5}'|sed 's/[^0-9]//g'

Last edited by Grazz256 (2010-01-26 20:25:04)

madeye · 2010-01-26 20:22:54

Thanks,
That's working perfect.

Is the -e switch necesary because the string must be processed twice?

janboe · 2010-01-26 20:47:58

I think you can do this even a little bit more easy:

amixer get Master | awk '$0~/%/{print $4}' | tr -d '[]'

or if you don't want the "%":

amixer get Master | awk '$0~/%/{print $4}' | tr -d '[]%'

You might have to replace $4 by $5

skanky · 2010-01-26 20:50:36

Here's mine. I use gawk, but I think awk will work, too.

amixer get Master | gawk '/Mono.+/ {gsub("\\[","", $4);gsub("\\]", "", $4);printf("%s",$4)}'

It should be slightly more efficient as there's fewer processes spawned, but that's theory I haven't tested.

I'm matching "Mono..." you may need to match differently, and $4 is my volume setting.
Also, I think it's possible to use just the one gsub, but I couldn't get that to work.

As an aside, another one I've used was this, which kept the [] as I used that to tell the difference between volume and other percentages in the status bar:

amixer get Master | awk '/Mono.+/ {print $6=="[off]"?$6:$4}'

This prints out [off] or the volume percentage, depending on if the volume is muted or not.

As usual, YMMV.

madeye · 2010-01-26 20:54:42

And then I learned something new again
Actually I didn't know about the tr command.

Thanks for all the solutions.

EDIT:
In case anyone is interested in my volume script, here it is:

#!/bin/sh

case $1 in
up)
    /usr/bin/amixer -q -c 0 sset 'Master' 5%+
    ;;
down)
    /usr/bin/amixer -q -c 0 sset 'Master' 5%-
    ;;
*)
    /usr/bin/amixer -q -c 0 sset 'Master' toggle
    ;;
esac

CURVOL=`amixer get Master | awk '/Mono.+/ {print $6=="[off]"?$6:$4}' | tr -d '[]'`

notify-send "Volume: $CURVOL"

I have added the following to my ~/.config/openbox/lxde-rc.xml

    <!-- volume control -->
    <keybind key="XF86AudioRaiseVolume">
      <action name="Execute">
        <command>amix.sh up</command>
      </action>
    </keybind>
    <keybind key="XF86AudioLowerVolume">
      <action name="Execute">
        <command>amix.sh down</command>
      </action>
    </keybind>
    <keybind key="XF86AudioMute">
      <action name="Execute">
        <command>amix.sh</command>
      </action>
    </keybind>

Last edited by madeye (2010-01-26 21:18:44)

robrene · 2010-01-26 22:53:41

You're using notify-send, if you want something a bit more cooler, look at this piece of python code I wrote a while back, it might inspire you

def notify():

    value = get_master_volume()

    if 66 < value <= 100:
        icon = "notification-audio-volume-high"
    if 33 < value <= 66:
        icon = "notification-audio-volume-medium"
    if 0 < value <= 33:
        icon = "notification-audio-volume-low"
    if value == 0:
        icon = "notification-audio-volume-off"

    if is_master_mute() == True:
        icon = "notification-audio-volume-muted"

    os.system("notify-send ' ' -i %s -h int:value:%s -h string:synchronous:volume" % (icon, value))

The notify-send line looks a little messy, but I'm sure you can figure it out.

notify-send ' ' -i $icon -h int:value:$volume -h string:synchronous:volume

Last edited by robrene (2010-01-26 22:57:18)

maximegb · 2010-02-03 19:56:01

Can be done in plain C :

#include <stdio.h>
#include <unistd.h>
#include <string.h>

int main(int argc,char *argv[])
{
    int pipe_fds[2],pid_amixer;
    
    if (argc<2) return 0;

    pipe(pipe_fds);

    if ((pid_amixer=fork())==0)
    {
        close(pipe_fds[0]);
        dup2(pipe_fds[1], 1);
        argv[0]="amixer";
        execvp(argv[0], argv);
    }
    else
    {
        char buffer[1024];
        char *tok;
        const char *target="Front Left:";
        int volume;
        char buf_is_on[6];
        int is_on;

        close(pipe_fds[1]);
        read(pipe_fds[0], buffer, 1024);
        close(pipe_fds[0]);

        if ((tok=strstr(buffer,target)))
        {
            sscanf(tok, "%*s %*s %*s %*s %*c%i%*s %*s %5s", &volume,buf_is_on);
            is_on=!strcmp("[on]",buf_is_on);
            printf("Volume = %d, is on = %d",volume,is_on);
            //instead of printf, you can exec notify-osd, etc...
        }
    }
    return 0;
}

Compile with :

gcc amixer-wrapper.c -o amixer-wrapper

Launch amixer-wrapper with usual amixer parameters, for instances:

amixer-wrapper get Master
amixer-wrapper set Master 3%+
amixer-wrapper set Master toggle

anrxc · 2010-02-04 01:41:10

Can be done in plain C

Of course it can be done in C. It can be done in anything. But do we want it to? Above shell script is just fine for a Linux user, a one-liner is simple and elegant, and those that did not employ anything other than awk especially so. Since you did write C maybe we will see other examples, maybe in Ruby?

Last edited by anrxc (2010-02-04 01:44:57)

Arch Linux

#1 2010-01-26 19:44:55

[SOLVED] how do I extract the mixer volume?

#2 2010-01-26 20:11:56

Re: [SOLVED] how do I extract the mixer volume?

#3 2010-01-26 20:22:54

Re: [SOLVED] how do I extract the mixer volume?

#4 2010-01-26 20:47:58

Re: [SOLVED] how do I extract the mixer volume?

#5 2010-01-26 20:50:36

Re: [SOLVED] how do I extract the mixer volume?

#6 2010-01-26 20:54:42

Re: [SOLVED] how do I extract the mixer volume?

#7 2010-01-26 22:53:41

Re: [SOLVED] how do I extract the mixer volume?

#8 2010-02-03 19:56:01

Re: [SOLVED] how do I extract the mixer volume?

#9 2010-02-04 01:41:10

Re: [SOLVED] how do I extract the mixer volume?

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