Add volume increment setting capability.

M  README
   Expanded.
M  vlm
   Add INC argument to increase and decrease sub-commands.
   Expand usage information output.

2 files changed, 34 insertions, 5 deletions

diff --git a/README b/README
index cc9db35..f813246 100644
--- a/README
+++ b/README
@@ -1,2 +1,18 @@
-The vlm script helps the user to easily set keyboard shortcuts to
-control pulseaudio volume, mute and switch pulseaudio output.
\ No newline at end of file
+The vlm script provides elementary sound control actions to set
+pulseaudio volume, mute or unmute sound and cycle through pulseaudio
+outputs, such that actions performed through this script will probably
+achieve sane results on all systems using pulseaudio. The script does
+not need any configuration from the user to perform its actions.
+
+It is provided so that the user can bind the script's actions to
+keyboard shortcuts of his choosing, and have those shortcuts trigger
+easy and consistent sound control actions.
+
+Because the script's capabilities are not exhaustive, and because it
+does not provide any output about their effects, it can not replace a
+full-blown sound mixer program.
+
+The script uses the pactl program to determine the currently active
+pulseaudio sink, then uses the same command again to perform its action.
+
+For usage information, type the command vlm without any argument.
diff --git a/vlm b/vlm
index b4b279b..fe62be4 100755
--- a/vlm
+++ b/vlm
@@ -45,10 +45,20 @@ fi
 
 case "$1" in
     increase)
-        pactl set-sink-volume ${SINKS[$IS]} "+5%"
+        if test "x$2" = "x"
+        then
+            pactl set-sink-volume ${SINKS[$IS]} "+5%"
+        else
+            pactl set-sink-volume ${SINKS[$IS]} $2
+        fi
         ;;
     decrease)
-        pactl set-sink-volume ${SINKS[$IS]} "-5%"
+        if test "x$2" = "x"
+        then
+            pactl set-sink-volume ${SINKS[$IS]} "-5%"
+        else
+            pactl set-sink-volume ${SINKS[$IS]} $2
+        fi
         ;;
     togglemute)
         pactl set-sink-mute ${SINKS[$IS]} toggle
@@ -67,7 +77,10 @@ case "$1" in
         done
         ;;
     *)
-        echo "Usage: /usr/local/bin/pavolctrl {increase|decrease|togglemute|nextsink}"
+        echo "Usage: vlm {increase [INC]|decrease [INC]|togglemute|nextsink}"
+        echo "  Volume increment INC is given as is to pactl."
+        echo "  Default INC is +5% for increase, -5% for decrease."
+        echo "  nextsink cycles audio outputs e.g. sound cards, usb, ..."
         exit 2
         ;;
 esac