61–70 of 191 posts
I'm sure this is very interesting but I couldn't make it past the first sentence. I'm sure there's a term for someone who writes like this, but all I could think was "redditspeak," or otherwise stale tryhard wacky. Forcibly inserting so much 'character' into your sentences that your syntax implodes.
You can't have "everything you wanted to know about terminals" with absolutely no mention of terminfo and (previously) termcap. You don't necessarily need ncurses to have a portable smart terminal experience, but you do need terminfo. ncurses magic relies on the lore stored in terminfo, which contains all of the obscure escape sequences and other information about the disparate world of terminals. They're maintained…
You can't have "everything you wanted to know about terminals" with absolutely no mention of terminfo and (previously) termcap. You don't necessarily need ncurses to have a portable smart terminal experience, but you do need terminfo. ncurses magic relies on the lore stored in terminfo, which contains all of the obscure escape sequences and other information about the disparate world of terminals. They're maintained…
[deleted]
It's not hard to find yourself with an incorrectly configured terminal on a modern Linux distro. For example, try running emacs inside tmux inside rxvt-unicode and find out how Ctrl/Shift/Ctrl+Shift with arrow keys are bound.
* The ESC [ command start sequence is actually a compromise for 7 bit systems. The [ character is not chosen by accident. It has an obvious positional relationship to ESC in the ASCII code which is why, informally, Ctrl-[ is the same as ESC.
* If you have an 8-bit-clean channel to the terminal, only a single character is required: the "upper escape" from the C1 control character set (0x80 to 0x9F). This character, 128 + 27 or 0x9B is called CSI: control sequence introducer, which is basically its role in these terminal control sequences. Thus ESC [ is just an alternative way of encoding CSI for 7 bit. E.g instead of CSI 4 A, you use ESC [ 4 A.
Earlier quoted context omitted.
You couldn't find an authoritative spec because there isn't a universal standard. Lots of terminal emulators differ in different ways.
https://www.ecma-international.org/publications-and-standard...
A while ago I was trying to find a way to make my terminal scroll back up after a command executed, so that if the output was long I could read it from the top without having to scroll up manually. There are ways to get yours shell to print something after the command executes, so I just needed to find an ansi escape sequence that would scroll up. Unfortunately I didn't see any sequences that do this. Anyone have any…
your_command_here | less
It will capture the output and let you scroll up and down.
Otherwise, this would really be a feature of the terminal, and not necessarily required to be supported (it makes sense when you consider that many early real terminals literally printed the output to paper -- who needs scroll-back, just look up the tape! And repeating previously shown output would result in a confusing print-out).
However, if your terminal emulator doesn't have a scroll-back, you could try something like tmux, or alternatively gnu screen. These add lots of little features to the terminal (a buffer to scroll back, split terminals, persistence so you can detach and reattach) (tmux is more modern feeling, IMO).
I was aware of the ANSI escape sequences and even used them directly in scripts on occasion, but I still used ncurses "where it mattered" because I didn't know about compatibility. I didn't want to risk Windows or a random flavor of linux I'd never heard of or a group of anti-VT100 enthusiasts getting upset because I didn't use an agreed upon compatibility layer. From the tone of this piece I gather that the ANSI esc…
Correct. Hardware terminals are extinct in the wild, and essentially all software terminals (including the Windows terminal!) now support a reasonable subset of "extended VT100" terminal control sequences. Some of the weirder features of the VT100 (like double-high/double-wide text or VT52 compatibility mode) are usually omitted, and some features which were added in later DEC terminals (like color) are often added.
A while ago I was trying to find a way to make my terminal scroll back up after a command executed, so that if the output was long I could read it from the top without having to scroll up manually. There are ways to get yours shell to print something after the command executes, so I just needed to find an ansi escape sequence that would scroll up. Unfortunately I didn't see any sequences that do this. Anyone have any…