<feed xmlns='http://www.w3.org/2005/Atom'>
<title>slosh.git/src/proto.c, branch docs-new</title>
<subtitle>an opinionated terminal multiplexer in C with programmable pane chrome</subtitle>
<id>https://git.sl0p.foo/slosh.git/atom/src/proto.c?h=docs-new</id>
<link rel='self' href='https://git.sl0p.foo/slosh.git/atom/src/proto.c?h=docs-new'/>
<link rel='alternate' type='text/html' href='https://git.sl0p.foo/slosh.git/'/>
<updated>2026-08-27T22:23:19Z</updated>
<entry>
<title>windows: a native port, on ConPTY and AF_UNIX</title>
<updated>2026-08-27T22:23:19Z</updated>
<author>
<name>Peter Geissler</name>
<email>peter@haxx.in</email>
</author>
<published>2026-08-27T22:11:24Z</published>
<link rel='alternate' type='text/html' href='https://git.sl0p.foo/slosh.git/commit/?id=d1b5a64c3855b07074b3c958739df4e16f6084a5'/>
<id>urn:sha1:d1b5a64c3855b07074b3c958739df4e16f6084a5</id>
<content type='text'>
slosh builds and runs on Windows 10/11, x86-64 and ARM64, as one exe
with no runtime dependency beyond the OS: panes, splits, tabs,
detachable sessions, the config file and its live reload, the control
socket, the mouse.

The port is a compatibility layer rather than a fork. compat/win holds
stub &lt;poll.h&gt;, &lt;sys/socket.h&gt;, &lt;termios.h&gt; and friends that redirect to
include/compat_win.h, which is force-included ahead of every translation
unit -- so the existing sources keep their POSIX includes and their
POSIX call sites, and the platform differences are answered in one
place.

Two decisions carry most of it.

Everything the event loop waits on is a socket. On POSIX a pty master,
an inotify descriptor and a unix socket are all file descriptors, so one
poll() covers them; Windows has no such union, and WSAPoll waits on
SOCKETs and nothing else. Rather than rewrite server.c's loop around
WaitForMultipleObjects -- which caps at 64 objects and cannot express
POLLOUT -- each non-socket source gets a pump thread that copies it into
one end of a loopback socketpair. The loop is then the POSIX one
unchanged, and only what sits behind the descriptor differs.

Socket descriptors are tagged rather than guessed: a wrapped SOCKET
comes back as SL_SOCK_BASE + slot, so read, write, close and poll can
tell a socket from a CRT descriptor with certainty instead of inferring
it from the numeric range. That is why socket() and accept() are shimmed
too -- an untagged descriptor escaping into the loop is the one failure
mode this scheme has, and it is worth closing completely.

Three things bit hard enough to be worth naming.

A pseudoconsole does not stop the child inheriting your stdio.
CreateProcess copies the parent's standard handles into the child when
STARTF_USESTDHANDLES is absent, and those win. With slosh's own stdout
redirected -- a pipe under ssh, a file under --script, a log under the
daemon -- the shell wrote its banner into slosh's output instead of into
the pane, and the pane had a correct title (ConPTY emits that itself)
over an empty body. The three handles are cleared for the duration of
the call, leaving the child nothing to inherit.

A ConPTY never reports EOF. The output pipe belongs to the
pseudoconsole, not to the child, so it stays open after the child exits
and pane_pump()'s read() -- the entire mechanism by which a pane learns
its program is gone -- never returns 0. A pane whose shell had been told
`exit` sat there looking alive forever. So the exit is waited for on the
process handle, and ClosePseudoConsole is what then produces the EOF.
That third thread is also why the per-pty state is reference counted: a
pump blocked on a dead pipe must not be waited for, or pty_close would
hang the session on the one program that misbehaves, so whoever finishes
last frees.

cmd.exe does not use CommandLineToArgvW's quoting. A literal quote is
\" to an ordinary program and a backslash-then-end-of-quoted-section to
cmd, so building `cmd /c notepad "C:\...\config.kdl"` the first way
handed the editor \"C:\...\config.kdl\", backslashes and all, and
notepad answered "Not a valid file name" about a path that existed.
cmd /c now gets the rest of the line verbatim -- the caller composed a
complete command with its own quoting, exactly as it does for sh -c.

Paths are mixed, and only some programs mind. slosh joins with '/' while
the environment supplies '\', so the config landed at
C:\Users\you/.config/slosh/config.kdl. The CRT opens that without
complaint, which is why --check reported it fine, but a GUI file dialog
rejects it outright. Anything handed to another program now goes through
sl_path_native() first; the internal representation is left alone.

The rest is small. Panes run %ComSpec%, sessions live in
%LOCALAPPDATA%\slosh rather than $XDG_RUNTIME_DIR because a session
socket must not follow a roaming profile to another host, there is no
SIGWINCH so a resize is noticed by comparing the console size on a
bounded poll, no fork so the daemon is a fresh detached process that
reconstructs its arguments on the command line, and no process group on
a pty so the foreground program is the youngest descendant of the pane's
shell. C-a e prefers whichever console editor is actually installed --
notepad is a GUI program, so a pane running it draws nothing and looks
broken -- and says so when it has to fall back.

make -f Makefile.windows ARCH=x86_64 (or aarch64) cross-compiles from a
mac or Linux, and builds natively on the box with zig on PATH.
</content>
</entry>
<entry>
<title>a client that stops reading must not stop the session</title>
<updated>2026-08-26T14:48:17Z</updated>
<author>
<name>Peter Geissler</name>
<email>peter@haxx.in</email>
</author>
<published>2026-08-26T14:44:33Z</published>
<link rel='alternate' type='text/html' href='https://git.sl0p.foo/slosh.git/commit/?id=9d5f9d2a1c3b8d0948a8efa8443a36847aa2107b'/>
<id>urn:sha1:9d5f9d2a1c3b8d0948a8efa8443a36847aa2107b</id>
<content type='text'>
Everything the server said went out through msg_send(), which loops on
sendmsg() until the kernel has taken all of it. That is a blocking write
to whoever is attached. A display whose reader has paused -- C-s at the
terminal, a stopped ssh, a client being swapped -- fills its socket
buffer, and then the *server* sits inside that loop: every other pane,
the config watcher, the control socket and every other connection stop
with it. A session that is supposed to outlive its client hangs on one.

macOS is where this showed up, because its socket buffers are a fraction
of Linux's 64K and it wedges within a screenful rather than after a few
hundred. `make test-live` could not get past the forty-connection probe
in test_session.py: the server was blocked writing to a pty nobody was
draining, so `slosh cmd panes` timed out and took the suite with it.

So connections are non-blocking and output is queued, flushed when
poll() says the socket will take more. The queue is capped: past 4MB we
are not buffering a slow reader any more, we are storing a screen nobody
is looking at, and the connection is dropped -- a display that comes
back reattaches and gets a full repaint, which is what happens after any
detach anyway.

Measured, with a pane running `yes` and a display that never reads:
before, the first control command hung forever; after, 40 of 40 are
answered, the session stays listed, and the server's RSS is flat.
</content>
</entry>
<entry>
<title>slosh: rename the project from sl0ppty</title>
<updated>2026-08-18T19:26:00Z</updated>
<author>
<name>user</name>
<email>user@clank</email>
</author>
<published>2026-08-18T19:26:00Z</published>
<link rel='alternate' type='text/html' href='https://git.sl0p.foo/slosh.git/commit/?id=b9e53cace4eb75263077df8623b011e66f5f2241'/>
<id>urn:sha1:b9e53cace4eb75263077df8623b011e66f5f2241</id>
<content type='text'>
sl0p + pty was error-prone to type and the zero made it worse; slosh
(slop + sh) is one syllable, impossible to typo, and slosh.foo is ours.

Mechanical rename everywhere it appears: binary, env vars (SLOSH,
SLOSH_SESSION, SLOSH_BIN, SLOSH_CONFIG), socket dir (/tmp/slosh-&lt;uid&gt;,
$XDG_RUNTIME_DIR/slosh), config path (~/.config/slosh), header guards,
src/sl0ppty.h -&gt; src/slosh.h, contrib/sl0ppty-dev -&gt; contrib/slosh-dev,
the driving-slosh skill, docs and tests. The sl0ppi fork references and
the sl0p theme stay: one is history, the other is the brand.

The rename surfaced a latent bug in test_osc5577: the hello-reply
answer always appeared on screen twice (ECHOCTL echo plus cat -v), but
a seven-character implementation name happened to wrap the second copy
across the 60-column boundary, so counting substrings in wrapped text
found one and passed for the wrong reason. A five-character name moved
the wrap and exposed it. The loop guard itself is correct -- with echo
off before the request there is exactly one reply -- so the test now
counts on de-wrapped text and tolerates the pane's own echo.
</content>
</entry>
<entry>
<title>sl0ppty: clang-format the tree</title>
<updated>2026-08-17T12:22:38Z</updated>
<author>
<name>user</name>
<email>user@clank</email>
</author>
<published>2026-08-17T12:22:38Z</published>
<link rel='alternate' type='text/html' href='https://git.sl0p.foo/slosh.git/commit/?id=ec91ccffe631ae34b111bf6161fd0e3c487f684c'/>
<id>urn:sha1:ec91ccffe631ae34b111bf6161fd0e3c487f684c</id>
<content type='text'>
The bumpy one. `make fmt` over every `.c` and `.h` outside `vendor/`: 32 files,
1,843 lines rewritten, no behaviour changed. Nothing here is worth reading -- the
next commit adds it to `.git-blame-ignore-revs` so `git blame` walks past it.

Two thirds of it is alignment the formatter now owns: trailing comments in a
struct, continuation lines under a signature. The rest is the hand-packed tables
opening up to one entry per line -- `ACTIONS`, `NAMED_KEYS`, `ACTION_HELP`. That
is a real loss of density and a real gain in diffs: adding an action was a reflow
of the block and is now one line. Anything worth keeping packed can be fenced with
`// clang-format off`; nothing was, on the grounds that a table is the thing a
formatter is for.

**One change is not formatting.** `src/config.h` had three trailing comments glued
onto one field:

    uint16_t hover_delay_ms; /* how long the pointer must rest to arm a guide */
    /* how long an announcement stays up */ /* rows per wheel notch */

-- `toast_ms`'s and `scroll_lines`' comments, landed on their neighbour by an
earlier edit, documenting the wrong things ever since. It is in this commit
because it is what caught it: clang-format could not settle on that line, wrapping
it one way and then re-indenting the wrap on a second pass, so `make fmt` was not
idempotent. The comments are back where they belong and it is.

Verified after the reformat, not before: `make clean &amp;&amp; make all` is
warning-free, `make retest` is 1801 checks green, and `make fmt` twice in a row
changes nothing the second time. A formatter that alters behaviour would be worse
than none, so the gate was the whole suite rather than a reading of the diff.
</content>
</entry>
<entry>
<title>sl0ppty: rename from sl0ptty</title>
<updated>2026-08-14T10:13:18Z</updated>
<author>
<name>user</name>
<email>user@clank</email>
</author>
<published>2026-08-14T10:13:18Z</published>
<link rel='alternate' type='text/html' href='https://git.sl0p.foo/slosh.git/commit/?id=20f269a0cdf65f196aea09f0279f5927f26d8192'/>
<id>urn:sha1:20f269a0cdf65f196aea09f0279f5927f26d8192</id>
<content type='text'>
A pty is a pseudo-terminal, and that is what this multiplexes: the extra t
was never standing for anything. Renaming now, while the only users are the
people who typed the old name on purpose, is cheaper than renaming later.

Mechanical, but not only cosmetic. The name is also the runtime contract, so
this moves $SL0PTTY and $SL0PTTY_CONFIG, ~/.config/sl0ptty/config.kdl, the
socket directory ($XDG_RUNTIME_DIR/sl0ptty, /tmp/sl0ptty-&lt;uid&gt;), and the
identity string a program gets back from an OSC 5577 hello. A session left
running under the old binary keeps its old socket directory and is invisible
to the new one; there is no migration and it does not seem worth writing one.

The sl0ppi fork keeps its name: it is a different thing, and D1 still points
at it.
</content>
</entry>
<entry>
<title>sl0ptty: M2 — server/client split, detach/reattach, control socket</title>
<updated>2026-08-13T20:52:33Z</updated>
<author>
<name>sl0p</name>
<email>sl0p@sl0p.foo</email>
</author>
<published>2026-08-13T20:52:33Z</published>
<link rel='alternate' type='text/html' href='https://git.sl0p.foo/slosh.git/commit/?id=7a6fa40a9c49245cf569e10e6ed635f9a6cbbcb7'/>
<id>urn:sha1:7a6fa40a9c49245cf569e10e6ed635f9a6cbbcb7</id>
<content type='text'>
The session now outlives its client, which is the point: agents keep running
while you are gone. The server owns the panes, the layout and the renderer;
the client is a terminal in raw mode and a socket, forwarding bytes and
painting what it is sent. It does not even decode input, so the decoder can
change without redeploying clients.

  sl0ptty            attach to 'main', creating it if nobody is home
  sl0ptty -s NAME    a named session
  sl0ptty ls         live sessions
  sl0ptty cmd LINE   one control command
  C-a d              detach

Connections are not clients. A connection becomes the display client only by
sending HELLO; control commands and liveness probes are just connections and
never displace anybody. This was found the hard way, one hour after the server
first ran: 'sl0ptty ls' kicked the attached client off, because ls connects to
see whether a socket answers. That is precisely the fault that gave the zellij
fork a 20-25% CLI failure rate, rebuilt and then fixed structurally. The
regression runs 20 x (ls + control) against a live client and demands 0
failures and a client that can still type.

cmd.c now holds the command vocabulary once, shared by the headless driver and
the control socket, so a script written against one works against the other —
'sl0ptty cmd "snapshot text"' against a detached session prints its screen.

tests/test_session.py: 18 checks over create, split, probe-resistance, detach,
survival, drive-while-detached, reattach, displacement and cleanup.
123 checks green overall.
</content>
</entry>
</feed>
