ucspi-tcp-ipv6

command-line tools for building TCP client-server applications (IPv6)

ucspi-tcp-ipv6 is the ucspi-tcp package with IPv6 support added. tcpserver waits for incoming connections and, for each connection, runs a program of your choice. Your program receives environment variables showing the local and remote host names, IP addresses, and port numbers. tcpserver offers a concurrency limit to protect you from running out of processes and memory. When you are handling 40 (by default) simultaneous connections, tcpserver smoothly defers acceptance of new connections. tcpserver also provides TCP access control features, similar to tcp-wrappers/tcpd's hosts.allow but much faster. Its access control rules are compiled into a hashed format with cdb, so it can easily deal with thousands of different hosts. This package includes a recordio tool that monitors all the input and output of a server. tcpclient makes a TCP connection and runs a program of your choice. It sets up the same environment variables as tcpserver. This package includes several sample clients built on top of tcpclient: who@, date@, finger@, http@, tcpcat, and mconnect. tcpserver and tcpclient conform to UCSPI, the UNIX Client-Server Program Interface, using the TCP protocol. UCSPI tools are available for several different networks.

ucspi-tcp

command-line tools for building TCP client-server applications

tcpserver waits for incoming connections and, for each connection, runs a program of your choice. Your program receives environment variables showing the local and remote host names, IP addresses, and port numbers. tcpserver offers a concurrency limit to protect you from running out of processes and memory. When you are handling 40 (by default) simultaneous connections, tcpserver smoothly defers acceptance of new connections. tcpserver also provides TCP access control features, similar to tcp-wrappers/tcpd's hosts.allow but much faster. Its access control rules are compiled into a hashed format with cdb, so it can easily deal with thousands of different hosts. This package includes a recordio tool that monitors all the input and output of a server. tcpclient makes a TCP connection and runs a program of your choice. It sets up the same environment variables as tcpserver. This package includes several sample clients built on top of tcpclient: who@, date@, finger@, http@, tcpcat, and mconnect. tcpserver and tcpclient conform to UCSPI, the UNIX Client-Server Program Interface, using the TCP protocol. UCSPI tools are available for several different networks.

courier-mta

Courier mail server - ESMTP daemon

The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols, such as ESMTP, IMAP, POP3, LDAP, TLS, and HTTP. Courier provides ESMTP, IMAP, POP3, webmail, and mailing list services within a single, consistent, framework. This package provides an ESMTP daemon which uses the Maildir format as native storage format, supports IPv6, implements SMTP extensions for mailing list management and features integrated mail filtering. It can function as an intermediate mail relay, relaying mail between an internal LAN and the Internet, or perform final delivery to mailboxes. ESMTP over TLS is handled by the regular ESMTP daemon in conjunction with the TLS wrapper.