osReadLine goes through the shell's editor now, so anything that asks the system
for a line gets arrows, Home, End and Delete. The editor is a program, and a word
typed with two letters the wrong way round can be put right without starting the
line again.
IT DOES NOT GET THE HISTORY, and that is the interesting half. Edit would
otherwise fill the history with the text of somebody's document, and pressing Up
in the middle of writing one would put "dir" into it. The history belongs to the
thing whose lines are commands. Two entry points rather than a flag the caller
sets first, so a caller cannot forget which it wanted.
And the console is put back the way it was FOUND rather than the way the shell
likes it. A program that had asked for key mode and then read a line through the
system used to be handed back a console in line mode having asked for nothing of
the sort. The status port reports all three things the control port can ask for,
in the same order two bits along, so one shift turns what the console IS into
what to write to make it that again.
Which uncovered a real fault in the console. READING THE STATUS PORT WAS EATING A
KEY: in line mode the poll consumed an arrow key and dropped it, so a program
that looked and then asked for key mode - exactly what reading a line now does -
found the first key it was reaching for already gone. A look must not consume
what it cannot report, because the mode can change. It is held now and delivered
as soon as something will take it. A blocking read still discards it, and must:
that read IS the delivery, and a byte held there would be met again forever.
Four recordings gained a program's echo, and cosmosEdit's went from
"> : : : : > : : > 1: alpha" to a session you can read. VERIFIED THE SAME WAY AS
BEFORE: with only the program side of the echo silenced, all 192 tests pass
against the recordings as they were before this commit, so the echo is the whole
of what changed.
cosmosEditService is the new test and it checks both halves at once. Inside Edit,
Left/Delete/Left puts "alpah" right. Up and Down do nothing there - were a
program's line walking the shell's history, the next line would come out as the
echo command from the top of the file instead of the word. And one press of Up
back at the prompt finds the command typed before Edit was started, which is the
proof that nothing the editor read went into the history at all.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW
AnachronautandClaude Opus 5
4d976fc22a