How to add the rest of the bytes to the buffer?

Question

Node.js

I create a buffer for two bytes, only one is written, how can I fill the last byte with 00? This option is not suitable because bl.length can be any length and 0 and 1 and 2 Wrote like this, but how terrible it is)
Buffer.alloc(2).write( String( bl.length ) )

Buffer.concat([Buffer.from([]), Buffer.alloc(2)])

Buffer.concat([ Buffer.from([bl.length]), Buffer.alloc(2 - Buffer.from([bl.length]).length ) ])

Answer 1

There are two functions for this
https://nodejs.org/api/buffer.html#buffer_buf_writ...
https://nodejs.org/api/buffer.html#buffer_buf_writ...
Same for reading only if BE write - do not read LE;)