See the perl network examples at Prof Golden's Perl Client server basics. Of course, it is basic Perl, but modules like IO::Socket and IO::Select make things easier. As far as writing and receiving simultaneously, there are 3 solutions: use IO::Select, fork, or use threads. Generally select is used when the messages are short, because the server will only handle one client at a time. If big files are transferred, you usually using a forking design.

It's a big topic, and you can search google and groups.google.com for "perl server client", "perl server IO::Select", "perl multi-echo chat", etc. There are many variations on server client setups. In general, for a client, you want a forking client. When it connects, it immediately forks off, one fork is solely for receiving, and 1 fork for sending. See Simple bi-directional forking commandline client for a basic client that should work with almost any server, like a telnet client.

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In reply to Re: Server/client sync - when can I write to a socket? by zentara
in thread Server/client sync - when can I write to a socket? by techcode

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