rtl-sdr @20220115-5e73f90f rtl_tcp does not listen on specified port

[Waffle2]

Using rtl_tcp on Macosx 12.5 does not work as expected. A command line such as -a 127.0.0.1 -p 1234 should result with rtl_tcp listening on port 1234. Instead, it gives a spurious bind error, and listens on what appears to be a random port.

rtl_tcp -a 127.0.0.1 -p 1234 
Found 1 device(s):
  0:  Realtek, RTL2838UHIDIR, SN: 00000001

Using device 0: Generic RTL2832U OEM
Found Rafael Micro R820T tuner
[R82XX] PLL not locked!
Tuned to 100000000 Hz.
rtl_tcp bind error: Invalid argumentlistening...
Use the device argument 'rtl_tcp=127.0.0.1:1234' in OsmoSDR (gr-osmosdr) source
to receive samples in GRC and control rtl_tcp parameters (frequency, gain, ...).
...
lsof -i -n | grep rtl
rtl_tcp   7371            dlr    5u  IPv4 0x4c8c6c1688efaf9d      0t0    TCP *:51345 (LISTEN)

Different runs appear to listed on other, random, ports.

[jmroot (Joshua Root)]

Are you doing this as root? If not, you won't be able to bind to ports below 1024, and presumably the software is automatically changing to a random unused port that will work.

[Waffle2]

Please note port 1234 > 1024. Yes, I tried as root, and as not root.