Autostart CAT servers with AetherSDR¶

Configure AetherSDR to start the rigctld TCP servers and/or PTY virtual serial ports automatically each time the application launches, so external logging and contest software is ready without manual intervention.

Before you start¶

AetherSDR must be connected to a FLEX-8600 radio before the CAT servers can operate. The autostart setting is saved regardless, but servers only become active once a radio connection is established.
Decide whether you need TCP, PTY (Linux/macOS only), or both. TCP works on all platforms; PTY is for applications that expect a serial device path.
PTY symlink paths are located in per-user runtime directories for security:
Linux: $XDG_RUNTIME_DIR/aethersdr/cat-A through cat-D
macOS: ~/Library/Caches/AetherSDR/cat-A through cat-D

Steps¶

Enable autostart for TCP servers¶

Open Settings > Autostart rigctld with AetherSDR.
Click the item to place a checkmark next to it.

AetherSDR will now start all four rigctld TCP servers automatically on the next launch. The base port persisted in CatTcpPort (default 4532) is used; channels bind to port, port+1, port+2, and port+3.

Enable autostart for PTY virtual serial ports¶

Open Settings > Autostart CAT with AetherSDR.
Click the item to place a checkmark next to it.

AetherSDR will now create the PTY symlinks under the per-user runtime paths automatically on the next launch: - Linux: $XDG_RUNTIME_DIR/aethersdr/cat-A through cat-D - macOS: ~/Library/Caches/AetherSDR/cat-A through cat-D

Verify the current session without restarting¶

If you want the servers running immediately in the current session as well:

Click the CAT tray button on the right sidebar to open the CAT Control applet.
Click Enable TCP to start the TCP servers now.
Click Enable TTY to start the PTY symlinks now (Linux/macOS only).

The channel rows (A, B, C, D) will update from (stopped) to :<port> (0 clients) as each server comes up. Each channel row also displays the current PTY path.

What each control does¶

Control	Kind	Default
`Enable TCP`	Toggle button	Off
`Enable TTY`	Toggle button	Off
`Base`	Text field	`4532`
A/B/C/D channel rows	Indicator	`(stopped)`

The per-channel PTY path indicator shows: - stopped when no PTY is active - The full symlink path (e.g., /run/user/1000/aethersdr/cat-A on Linux or ~/Library/Caches/AetherSDR/cat-A on macOS) when the PTY is running

Tips¶

The Enable TCP toggle in the applet reflects the AutoStartRigctld setting. The Enable TTY toggle reflects the AutoStartCAT setting. Toggling either button in the applet updates the autostart preference at the same time, so you can use the applet buttons instead of the Settings menu if you prefer.
If you change the Base port after enabling autostart, the new port is saved to CatTcpPort and the running servers restart on the new base immediately. The saved value is used on the next autostart as well.
In v26.5.3, AetherSDR includes a native Hamlib NET rigctl implementation, replacing the need for a standalone rigctld bridge. Slices A–H each expose a TTY (per-user runtime path) and a TCP port (4532–4539).
PTY symlink creation uses atomic replacement (symlink + rename) to prevent TOCTOU race conditions (GHSA-qxhr-cwrc-pvrm).

Troubleshooting¶

Servers do not start after launch even though autostart is enabled — The radio must be connected before the servers become active. Confirm the connection state in the title bar and retry once connected.
PTY symlinks do not appear — The Enable TTY autostart is only functional on Linux and macOS. On Windows, Enable TTY has no effect. On Linux, verify that $XDG_RUNTIME_DIR is set (typically /run/user/<uid>).
Port already in use — If another application occupies a port in the Base–Base+3 range, the corresponding server will fail silently. Change the Base value in the CAT Control applet to an unused port range and re-enable TCP.
Channel badge colours appear incorrect — Slice colours are managed dynamically. If badges show unexpected colours, disconnect and reconnect to the radio so that slice colour assignments are refreshed.