未知的 ANSI 转义序列

Question

I'm trying to create a HTML terminal emulator. With most of the formatting code I'm OK, pages like this are a great help. However the line containing the prompt is strange (string, then the ASCII codes below):

\e]0;pi@igor: ~{??}\e[01;32mpi@igor:[01;34m~ $  
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27 93 48 59 112 105 64 105 103 111 114 58 32 126 7 27 91 48 49 59 51 50 109 112 105 64 105 103 111 114 27 91 48 48 109 58 27 91

First of all, at the beginning of the line there's this \e] (Esc + closing bracket.) sequence I don't see in the docs, With an opening bracket it would be better. but even that I can't find in the reference.

The next thing is that char code 7 that I replaced with {??} in the string. Right after the prompt there's a single byte 7.

The actual prompt here is

pi@igor:~ $ 

with formatting (and igor is a Raspberry Pi), so the string is perfectly fine (even if truncated by me) after the {??} part, ie char 7. But what is it before that?

Edit: so yes, char 7 would be the bell in ASCII. If it's that, why does it have the full prompt go with it?

Answer 1

It is setting the terminal title to pi@igor: ~ which is done by the first part \e]0;pi@igor: ~\a .

The comment by dave_thompson_085 reports that this is an xterm sequence:

This is an xterm defined sequence, not ANSI or DEC. See https://invisible-island.net/xterm/ctlseqs/ctlseqs.html#h2-Operating-System-Commands (and the top of the page where OSC is explained as ESC ] or \x9D).