s6-networking: the s6-ident-client program

The `s6-ident-client` program

s6-ident-client is a command-line client application that performs IDENT (RFC 1413) queries.

Interface

     s6-ident-client [ -t millisecs ] remoteaddr remoteport localaddr localport

s6-ident-client contacts the IDENT server on address remoteaddr port 113 and asks it about the connection from address remoteaddr port remoteport to address localaddr port localport.
It prints the answer to stdout.
It exits 0 if the answer is positive or 1 if the answer is negative, in which case it also prints an informative message to stderr.
remoteaddr and localaddr can be either IPv4 or IPv6 addresses; however, they must both be of the same type.

-t millisecs : if no answer has been obtained within millisecs milliseconds, s6-ident-client will exit 99 with an error message. By default, millisecs is 0, which means no time limit.