A command line runs as its own command pane unless it is clicked at a shell's prompt

A middle click, an exec write or a tag word that no builtin knows was typed
into some terminal for the pane's directory, sharing whatever state that
shell was in and answering nothing, so a misspelling vanished into a shell.
Now only a line clicked at an interactive terminal's prompt is typed there.
From anywhere else it runs as a command pane: a terminal whose child is
$SHELL -c the line in the pane's directory, full emulation, which shows its
output and then exit N from the host's reaping of the child, and stays. A
finished command pane is the next command's for its directory, which runs
below what it showed after a '% line' line (acme appends to +Errors and never
clears it, util.c:213); a running one gets a second pane. Kill ends a command
pane's whole process group, the log records run and exit, exec reads back the
command pane's serial, and a line is at most 1 KB, read off the pane as the
host forks rather than carried in every spawn effect. ttyForDir's search for
a free shell is gone. The goldens of chordcut, cmdword and layout-open change
where a file's exec now opens a command pane, and ttytaken is rewritten to
exec from the terminal itself; docs/open-questions.md records the decision.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 15 insertions, 0 deletions

diff --git a/src/builtins.zig b/src/builtins.zig
index d06897ff..19d16e1e 100644
--- a/src/builtins.zig
+++ b/src/builtins.zig
@@ -419,6 +419,21 @@ pub const Kill = struct {
         var jobless = false;
         for (c.p.panes, 0..) |slot, id| {
             const pane = slot orelse continue;
+            // A command pane's child is the command: the whole of its
+            // process group goes, as acme's Kill ends the process.
+            if (pane.command) |line| if (!pane.command_done) {
+                const said = std.mem.trim(u8, line, " \t");
+                const first = said[0 .. std.mem.indexOfAny(u8, said, " \t") orelse said.len];
+                if (names.len > 0) {
+                    var words = std.mem.tokenizeAny(u8, names, " \t");
+                    while (words.next()) |w| {
+                        if (std.mem.eql(u8, w, first)) break;
+                    } else continue;
+                }
+                c.p.emit(.{ .signal_pty = .{ .pane = @intCast(id), .sig = .term } });
+                stopped = true;
+                continue;
+            };
             if (!panes.Terminal.commandRunning(pane)) continue;
             const sent = pane.sent_command.?;
             if (names.len > 0) {