Comment 29 for bug 1297051

With the disclaimer that the original report was from 9 years ago(!) ... the application does *not* use C1 controls *with* UTF-8 text. That was just an observation on my part regarding how the character set and encoding would impact on any attempt to change the implementation to recognise C1 controls. The application has no support for Unicode characters in general and hence no need for UTF-8. Everything is effectively ISO-8859-1 i.e. clean traditional vanilla 8 bit data.

gnome-terminal is used here to access a "mainframe" host on the network that runs an in-house application. This host does not run Linux (shocking, I know). Hence I can assure you that it uses C1 controls but you will not be able to verify that. :-) This application would be described as "legacy" but 9 years down the track and it is still lingering on.

*Some* of the relevant escape sequences or other controls that exist in both a two-byte 7 bit form and a one-byte 8 bit (C1) form - as far as traditional 8 bit data goes - are mentioned above.

At a quick look, some of the relevant sequences that are actually used in the application:

RI = Reverse Index - used to move the cursor up, or scroll the scrolling region if the cursor is already at the top line of the scrolling region

CSI = Control Sequence Introducer - used for zillions of terminal escape sequences (and this was the main one that was causing a problem)

OSC = Operating System Command - has several functions but used here to set the window title and icon title

ST = String Terminator - used in several functions but used in setting the window title and the icon title and, more interestingly, used in sixel mode when drawing barcodes :-0