vznnc: Run a program connected to a socket

SYNOPSIS

\$1 { -l | -c } -p port program [arg ...]

DESCRIPTION

This "nano-netcat" utility can be used to either listen on or connect to a TCP port at localhost, and run a specified program with its stdin and stdout (or a specified file descriptor) connected to the socket.

OPTIONS

-l: Listen on a specified TCP port at localhost.
-c: Connect to a specified TCP port at localhost.
-p port: Port number.
-f fd: File descriptor ID. If this option is not set, stdin and stdout are closed and are connected to the socket, otherwise they are left intact, and the specified fd is used.
--: This is a separator between vznnc own arguments and program arguments, so that latter won't be processed by vznnc. It is required in case there are any arguments to program that start with the dash (-) character, and is optional otherwise.
program [ arg ... ]: Program to run, with optional arguments.

EXIT STATUS

Returns program exit status upon success, or one of the following codes in case of an error:

1: Invalid usage
127: Error executing program.
220: Network-related error.

EXAMPLES

To run receiving side of ploop copy command on a remote server, using openssh port forwarding:

 PORT=2345
 ssh -L localhost:$PORT:localhost:$PORT $REMOTE_SERVER \
	vznnc -l -p $PORT -- ploop copy -d $FILE -i0 -o1

To do the same, but with stdin and stdout intact, using file descriptor 5 for communication:

ssh -L localhost:$PORT:localhost:$PORT $REMOTE_SERVER \ vznnc -l -p $PORT -f 5 -- ploop copy -d $FILE -i5 -o5

RELATED TO vznnc…

nc(3), netcat(3), socat(2).

vznnc (8)