nc -b flag bad interface name

FWIW, on my Mac, running macOS Sequoia, the following is the proper syntax for the nc command:

• usage: nc [-46AacCDdEFhklMnOortUuvz] [-K tc] [-b boundif] [-i interval] [-p source_port]

And man nc reveals:

SYNOPSIS

   nc [-46AcDCdhklnrtUuvz] [-b boundif] [-i interval] [-p source_port]

    [-s source_ip_address] [-w timeout] [-X proxy_protocol]

    [-x proxy_address[:port]] [--apple-delegate-pid pid]

    [--apple-delegate-uuid uuid] [--apple-ext-bk-idle]

    [--apple-nowakefromsleep n] [--apple-ecn mode] [hostname] [port[s]]

... and as etresoft has eluded to:

-b boundif

       Specifies the interface to bind the socket to.

According to the man page, you have to supply an interface name with the -b flag.

Try en1, en2, etc.