Expand description
Stable per-machine identifier used to deduplicate device rows on the relay.
The relay uses machine_id to recognize when the CLI and desktop on the
same Mac are signing in independently and should share a single device row
instead of producing two. The value is opaque (SHA-256 of the OS-provided
UUID, truncated to 16 hex chars) so the underlying hardware identifier is
never sent in cleartext.
Sources by platform:
macOS — IOPlatformUUID via ioreg -rd1 -c IOPlatformExpertDevice
Linux — /etc/machine-id (or /var/lib/dbus/machine-id fallback)
Windows — HKLM\SOFTWARE\Microsoft\Cryptography\MachineGuid
Returns an empty string when the source is unavailable; callers treat that the same as “no dedup hint” and the relay falls back to today’s behavior.
Functions§
- hostname_
or_ unknown - Returns the OS-level hostname via
gethostname(3), or"unknown"if the syscall fails or yields an empty value. Identical on CLI and desktop so the relay’s source_key dedup matches across both clients on the same Mac. - in_
ssh_ session - Returns true if the current process appears to be running inside an SSH
session, based on the SSH_* environment variables OpenSSH’s sshd sets
when forking a login shell. Suppresses browser auto-open and desktop
handoff during
cinch auth login. - self_
source_ key - Returns the
sourcevalue used when this device pushes a clip. - stable_
machine_ id - Returns a stable, opaque identifier for this machine, or an empty string if no source is available. The value is suitable for sending to the relay (no raw hardware ID) and is consistent across CLI and desktop on the same machine.