self-update

Updates turnout itself to the newest release.

turnout self-update

turnout 0.24.1 is available (you have 0.24.0).
It will replace /home/dev/.local/bin/turnout
Update now? yes
Updated to turnout 0.24.1
/home/dev/.local/bin/tn updated too.

Flag	Short	Effect
--yes	-y	Skip the confirmation prompt
--force	-f	Replace the binary even when a package manager owns it

It exits without doing anything when you are already on the latest release.

Installations it does not touch

Only installations that came from a release archive - the installers or a manually unpacked release - are replaced in place. When cargo, npm or a system package manager put turnout there, that tool keeps its own record of what is installed, and overwriting the file behind its back would leave it convinced the old version is still present.

Those cases print the command that actually updates them:

$ turnout self-update
turnout was installed with cargo, which keeps its own record of what is installed.

Update it with:
  cargo install turnout --force

--force replaces the binary anyway. It exists for the case where the guess is wrong, not as the normal path - if the guess was right, the package manager’s records go stale.

Replacing a running binary

The executable being replaced is the one currently running. Windows keeps it locked and refuses the write, so the outgoing binary is renamed to turnout.exe.old first - a rename is allowed while the image is mapped - and the new one takes its place.

That leftover is deleted by the next turnout command you run, whatever it is, since by then it is no longer the running image. Unix does not need the dance, but follows the same path so there is one behaviour to reason about.

If installing the new binary fails partway, the old one is moved back: the command never leaves you without a working turnout.

The tn alias

The short alias is a link to the binary rather than a copy of it, so both names always answer with the same code - there is nothing to keep in sync, and an install costs one binary instead of two.

The swap above breaks that link, though: it renames the file being replaced. So the other name is pointed back at the new binary as the last step of an update, and the command says so when it does.

Which name that is depends on how you started the update. self-update replaces the file it is running from, so tn self-update replaces tn and repairs turnout, exactly mirroring the usual direction. Either way both names end up on the new release.

An install without an alias does not grow one - TURNOUT_NO_ALIAS=1 is a choice the update has no business overruling. And if the relink fails, the command says that too, because a stale alias keeps answering under its own name:

Warning: /home/dev/.local/bin/tn still points at the previous version and could not be relinked (permission denied).
Re-run the installer to fix it.

Updating while the gateway or a dev server is running

You do not have to stop anything first. Both turnout gateway start and turnout dev leave a second turnout process running from the same executable, and the update succeeds anyway - for the same reason as above. The lock is on the file, not on the name, so the running process keeps executing the image that was renamed out of the way.

What it does mean is that already-running processes keep running the old code. They were loaded into memory before the swap and nothing reaches back into them:

Running	After self-update	To pick up the new version
turnout gateway	Keeps serving, on the old code	turnout gateway stop && turnout gateway start
turnout dev	Keeps running, on the old code	Stop it (Ctrl+C) and start it again

Nothing breaks either way - a restart is only needed when the new release changes something you actually want in those processes.

One consequence worth knowing: while the old image is still executing, its .old file cannot be deleted. The sweep skips it silently and removes it after the process has exited.

Where the release comes from

The tag is read from the /releases/latest redirect on github.com and the matching archive is downloaded from that release - the same source the installers use, and deliberately not api.github.com, whose unauthenticated rate limit is shared by everyone behind your IP address. See the update check for the rest of that reasoning.

Prebuilt binaries exist for x86-64 Windows, x86-64 Linux and Apple Silicon macOS. On any other platform the command says so and points at cargo install turnout --force.