qr:tldr:0a89c

This command is used to display and encode data into a QR code with specified error correction level.

Here's how it works:

1. echo "${data}":

   • echo is a command that outputs the given text or value.
   • "${data}" is a shell variable that represents the data to be encoded into the QR code. The content of this variable will be displayed as the input to the next command.

2. | (pipe):

   • The pipe "|" is used to redirect the output of the preceding command (echo "${data}") as the input to the following command (qr --error-correction=${select}).

3. qr --error-correction=${select}:

   • qr is a command-line tool used to generate QR codes.
   • --error-correction=${select} is an option to specify the error correction level for the QR code.
     • ${select} is a shell variable that represents the selected error correction level for the QR code. The actual value of this variable will be inserted in place of ${select}.
     • Error correction level determines the amount of data that can be recovered if the QR code is damaged or partially obscured. It can be set to various options such as L (low), M (medium), Q (quartile), or H (high).

Overall, this command takes the value of the data variable, displays it, and pipes it as the input to the qr command with the specified error correction level. The qr command will generate a QR code representation of the data based on the chosen error correction level.