Re: /dev/tcp

Eli the Bearded <*@eli.users.panix.com> wrote:
> What system(s) have /dev/tcp/* natively?

What "systems"?  Only those with a /bin/bash compiled with this 
"special bash feature" compiled in.

>   $ man bash
>   [...]
>   REDIRECTION
>   [...]
>        Bash handles several filenames specially when they are used in
>        redirections,  as described  in the  following table.   If the
>        operating  system on  which  bash is  running  provides  these
>        special files, bash will use them;  other wise it will emulate
>        them internally with the behavior described below.
>   [...]
>               /dev/tcp/host/port
>                   If  host  is a valid  hostname or Internet address,
>                   and port is an integer port number or service name,
>                   bash attempts to open the corresponding TCP socket.
> 
> I don't see it on the various systems I have handy (Debian 13, Amazon
> Linux 2023, Mac OS 15.7.x, NetBSD 10.1, Android 14).

> is it a plan9 thing?

It's a Bash feature.  Note the man page quote you provided:

>  **Bash** handles several filenames specially when they are used in 
>  redirections

These are handled by Bash, they don't exist as part of the OS (system).