When the terminal is in UTF-8 mode, we accumulate UTF-8 text normally
in the OSC string buffer - but the byte 0x9C is interpreted as the C1
control character String Terminator, which terminates the OSC
sequence. That's not really what you want in UTF-8 mode, because 0x9C
is also a perfectly normal UTF-8 continuation character. For example,
you'd expect this to set the window title to "FÜNF":
echo -ne '\033]0;FÜNF\007'
but in fact, by the sheer chance that Ü is encoded with an 0x9C byte,
you get a window title consisting of "F" followed by an illegal-
encoding marker, and the OSC sequence is terminated abruptly so that
the trailing 'NF' is printed normally to the terminal and then the BEL
generates a beep.
Now, in UTF-8 mode, we only support the C1 control for ST if it
appears in the form of the proper UTF-8 encoding of U+009C. So that
example now 'works', at least in the sense that the terminal considers
the OSC sequence to terminate where the sender expected it to
terminate.
Another case where we interpret 0x9C inappropriately as ST is if the
terminal is in a single-byte character set in which that character is
a printing one. In CP437, for example, you can't set a window title
containing a pound sign, because its encoding is 0x9C.
This commit by itself doesn't make those window titles _work_, in the
sense of coming out looking right. They just mean that the OSC
sequence is not terminated at the wrong place. The actual title
rendering will be fixed in the next commit.
This is the README for PuTTY, a free Windows and Unix Telnet and SSH
client.
PuTTY is built using CMake <https://cmake.org/>. To compile in the
simplest way (on any of Linux, Windows or Mac), run these commands in
the source directory:
cmake .
cmake --build .
Documentation (in various formats including Windows Help and Unix
`man' pages) is built from the Halibut (`.but') files in the `doc'
subdirectory using `doc/Makefile'. If you aren't using one of our
source snapshots, you'll need to do this yourself. Halibut can be
found at <https://www.chiark.greenend.org.uk/~sgtatham/halibut/>.
The PuTTY home web site is
https://www.chiark.greenend.org.uk/~sgtatham/putty/
If you want to send bug reports or feature requests, please read the
Feedback section of the web site before doing so. Sending one-line
reports saying `it doesn't work' will waste your time as much as
ours.
See the file LICENCE for the licence conditions.