Help with MMM-PIR-Sensor tvservice logical evaluation

[orayoflighto]

Can someone help shed some light on this piece of code in the MMM-PIR-Sensor module? In the node_helper.js there is:

      // Check if hdmi output is already on
      exec("/opt/vc/bin/tvservice -s").stdout.on('data', function(data) {
        if (data.indexOf("0x120002") !== -1)
          exec("/opt/vc/bin/tvservice --preferred && chvt 6 && chvt 7", null);

I understand what it is doing. It is checking if the monitor is in standby [TV is off] and if so then it turns it on. This bit of code also executes when the monitor is on though which is the part that I am having trouble with. I understand that 0x120002 is what tvservice reports when the monitor is off. I don’t understand the!== -1

Any help? I would like to change the logic so it doesn’t execute that line when the monitor is on (0x12000a)

[strawberry 3.141]

@orayoflighto if there is no occurence of the string 0x120002, the method indexOf returns -1. So he checks if the string 0x120002 is part of the variable data.

[orayoflighto]

I figured it out. There are missing brackets for the if statement. In node_helper.js:

From:

        if (data.indexOf("0x120002") !== -1)
          exec("/opt/vc/bin/tvservice --preferred && chvt 6 && chvt 7", null);

To:

        if (data.indexOf("0x120002") !== -1){
          exec("/opt/vc/bin/tvservice --preferred && chvt 6 && chvt 7", null);
       }

@paviro