an opinionated terminal multiplexer in C with programmable pane chrome https://git.sl0p.foo/slosh.git/atom/?h=v0.1.1 2026-08-27T14:31:56Z 2026-08-27T14:31:56Z Peter Geissler peter@haxx.in 2026-08-27T14:31:02Z urn:sha1:b380d3541d71ee2a94b4bda3b99182eddd153851 On Darwin a pty master has no line discipline until its slave has been opened: every TIOCSWINSZ on the master until then fails with ENOTTY and the size is dropped without a word. A pane is born 1x1 and told how big it really is by the layout an instant after the fork -- and with the child doing the open(), that message raced the child and usually lost. Nothing ever sent it again, so the program in the pane spent its whole life believing it had one row and one column. `C-a e` hit it every time, because the editor's pane is always brand new: nvim drew its screen into two rows in the corner of a 94x15 pane. The old code knew half of this -- the child set the winsize on the slave it had just opened, which is what kept a fresh pane from being 0x0 -- but that only fixed the *spawn* size. Every resize after it still went to a master that might not have a slave yet. So open the slave here, before the fork, and let the child inherit it. The fork copies the fd table, so the slave is open from the child's first instruction and every resize the parent sends afterwards lands; BSD's forkpty() does the same thing for the same reason. The winsize is set on that slave before the fork, which orders it ahead of anything the parent sends later, and the child no longer sets it at all: by the time the child ran, the size it was spawned with could already be stale, and writing it back would undo the very resize this is about. test_pty_size.py asks the pane's own program what size it thinks it is -- for the first pane, for a pane from a split, and after a resize -- and compares it to the pane. It printed "1 1" against a 74x18 pane before this. live_m0.py asked `tput cols`, which needs a terminfo entry for xterm-ghostty and therefore fails on most macs for a reason that has nothing to do with resizing. `stty size` asks the tty itself, which is the thing under test. 2026-08-27T14:27:13Z user user@clank 2026-08-27T14:27:13Z urn:sha1:21a2a39a3b27ff4625bbc1d89220fa83e923ecf8 The vendored tree has no .git, so upstream's version detection runs git describe in *our* repository -- and the moment this repo grew its first release tag (v0.1.0), ghostty's build refused it: 'tagged releases must be in vX.Y.Z format matching build.zig'. Our v0.1.0 is not ghostty's 1.3.2-dev, and upstream is right not to let a stranger's tag name its build. -Dversion-string is upstream's own escape hatch for exactly this. The value is read from the vendored build.zig.zon rather than written here, so a re-vendor updates it in the one place it already lives. Both invocations (the host vendor target and the cross-built release legs) get it through one VT_FLAGS. 2026-08-27T14:19:25Z user user@clank 2026-08-27T14:19:25Z urn:sha1:b6fb41cea7610e56280a4db6572bbad955a9b667 'With Homebrew (macOS or Linux)' followed by a source build made every reader parse which half was theirs; now macOS and Linux each have a heading, and you read yours. macOS is the tap; Linux is the same tap under Homebrew on Linux, or the source build, which the docs landing page had never mentioned brew at all. Also fixes the README telling people to run bare 'make', which prints the help text (the default goal) and builds nothing. install.sh had this figured out and commented on it; the README had not. 2026-08-27T14:11:26Z user user@clank 2026-08-27T14:11:26Z urn:sha1:238b1a7eb51c576254537705597f8a039e1d9c86 Some 230 sentences hung their qualifications between dashes, and at that density the tic reads as the writing's signature rather than a tool it occasionally picks up. Each one is now the punctuation the sentence actually wanted: a colon where the aside defines, parentheses where it whispers, a comma where it barely pauses, a full stop where two thoughts were pretending to be one. Definition lists and reference tables take colons throughout. Two double hyphens remain on purpose, both literal: the argv separator in a shell example, and a table cell that means 'takes nothing'. 2026-08-27T14:04:37Z user user@clank 2026-08-27T14:04:37Z urn:sha1:5151e42f22b404cf41dc8b409bcdfcd4b39444ea Every C comment, commit message and generated config in this repo writes the aside dash as a spaced double hyphen; the Markdown alone used U+2014, some 220 of them. One spelling, and the ASCII one -- the prose now matches the code it documents. Mechanical (every occurrence was the spaced form, checked including the one inside a code fence, where it was comment text), so the words themselves are untouched. 2026-08-27T14:04:37Z user user@clank 2026-08-27T14:04:37Z urn:sha1:c76159dd380bf5a37d1a24e5295c42c626090c5c The 'Why another one' section was two paragraphs of case-making against other multiplexers, and a landing page that defends its existence reads as unsure of it. What the section said truthfully -- the vendored core, recompute-not-remember, scriptable to its depth -- design.md already says where it belongs. The one-line closer stays: 15k lines of C and no dependencies is a fact, not a defence. 2026-08-27T14:02:11Z user user@clank 2026-08-27T14:02:11Z urn:sha1:d7742f16b81ef09e74c0cbe6999d07100e5ef63c Same reasoning as the README's (24a6db01): the sketch says nothing the first paragraph did not, and on the rendered site it sat where the reader was deciding whether to keep reading. 2026-08-27T13:58:35Z user user@clank 2026-08-27T13:58:35Z urn:sha1:24a6db01b24b8ef4cfae42e18284e1168cbca0df Sixteen lines of box-drawing was the biggest thing on the page and the least true: a static sketch of two frames says nothing the first paragraph had not already said, and the real look -- themes, compact borders, shaders -- is not something a code block can be honest about. The docs site keeps its copy; the README gets to the install command sooner. 2026-08-27T13:27:51Z user user@clank 2026-08-27T13:27:51Z urn:sha1:b5df6a7b1d73fc9740a077e8eca2d7fc8f6afe60 Section 5 is where unix keeps its file formats, and slosh has two documents sharing one syntax -- the configuration and the layouts -- so they share a page the way they share a parser. docs/slosh.5 covers the KDL subset, where the file lives and how reload refuses a broken one, include and its precedence, every top-level setting grouped the way config.md groups them, the theme block, the shader vocabulary with the expression language summarised, the states and their ranking, the keys block including direct bindings, and the layout schema (tab, pane, and their properties). Held to the source like slosh.1 before it: every name in config.c's KNOWN_TOP -- the list the loader refuses unknown settings against, itself held to the loader by test_config.py -- must appear in the page, so a knob cannot be added without this page hearing about it. The pair must cross-reference each other, and both must be pure ASCII and lint clean under groff -ww. slosh(1) grows a SHADERS section -- the one feature a synopsis reader would never guess a multiplexer had -- and its SEE ALSO now names slosh(5) and nothing else: the other multiplexers can advertise themselves. Install puts the page under share/man/man5, the release tarballs carry both pages, and the Homebrew formula installs what the commit it is building has, guarded as before. 2026-08-27T13:17:57Z user user@clank 2026-08-27T13:17:57Z urn:sha1:ee5790225261fb3d473a16a365bedc15619f93cc The distributables were a bare binary and a directory of Markdown, which is fine until somebody types 'man slosh' -- the unix-traditional place to ask. docs/slosh.1 is hand-written man(7), pure ASCII roff, no toolchain: the synopsis, the options, the session commands, the default keys, the mouse (including the new drag-past-an-edge scrolling), where the configuration lives, what SLOSH_* means in a pane's environment, files, exit status. The prose docs stay the long form; the page says so and points at them. 'make install' puts it under PREFIX/share/man/man1 (and uninstall takes it away), the release tarballs carry it beside the LICENSE -- a tarball is what a packager starts from -- and the Homebrew formula installs it when the commit it is building has one, guarded because the formula must be able to build commits older than the page. Prose about a program drifts unless something holds them together, so test_docs.py holds the page to the source the way it already holds the site to docs/nav: every option main.c's parser compares against and every word command must appear in the page, every SLOSH_* variable the code reads or sets must be documented, the roff must be pure ASCII (it travels through implementations that never heard of preconv), and where groff exists the page must lint clean at CHECKSTYLE=3 with -ww. Adding a flag without documenting it is now a failing test, which is the only kind of documentation policy that survives contact with a deadline.