Add escape for reading clipboard

[chrisduerr]

No description provided.

[kchibisov]

Are we trying to follow what xterm does or we'd have our own approach on handling this?

Just reading through xterm spec https://invisible-island.net/xterm/ctlseqs/ctlseqs.html#h3-Operating-System-Commands . It seems it's a bit more tricky then just check first char of 1 parameter.

The first, Pc, may contain zero or more characters from the set c , p , q , s , 0 , 1 , 2 , 3 , 4 , 5 , 6 , and 7.

[chrisduerr]

It seems it's a bit more tricky then just check first char of 1 parameter.

That's correct, however I don't think we need to support the full spec. Our clipboard library doesn't even support all these different buffers, so there's no way we could support them. So we just support the part of the spec that is most likely to be used.

So we do p/s => selection clipboard and c => clipboard. The rest q/0-7 we can't support with our clipboard library, so we just throw it away.

I think that's a reasonable minimal implementation to follow and I don't expect that we really need to support any more than this. Considering how most terminal emulators (like VTE and URxvt) don't support this at all and even XTerm requires configuration to support setting the clipboard data.

[kchibisov]

I'm not worry about supporting full spec, I worry about your p,s,c parameters being missed, due to things like 0pc, since the spec isn't clear here. Am I correct that it shouldn't happen?

[chrisduerr]

I'm not worry about supporting full spec, I worry about your p,s,c parameters being missed, due to things like 0pc, since the spec isn't clear here. Am I correct that it shouldn't happen?

Honestly I don't 100% know myself how the other buffers work, but 0c as a parameter in the second position does not work with xterm. My assumption is that the buffers are set using q0 - q7 as second parameter and p c s are only valid on their own.

So I think we should be good the way we're doing it here. We're not supporting q and the multiple buffers, but that's just a completely missing feature, but everything else involving the clipboards we support ourselves seems to work exactly as it does in XTerm.

If you want to test it yourself and find anything else, please let me know. But I think our behavior should be correct for the things we do support.

[kchibisov]

Honestly I don't 100% know myself how the other buffers work, but 0c as a parameter in the second position does not work with xterm.

That's what I'd like to hear. I was wondering whether I can write to Selection and Clipboard, by sending just one escape, since xterm spec says, you can pass more then one char, but doesn't emphasize that p,c,s should be used on their own.

So, looks good to me.