Yes, they do indeed block, but it sounds like blocking semantics are what you are looking for. Writing non-blocking code is a non-trivial task (especially if you want cross-platform compatibility).

If you did indeed fcntl the socket to O_NONBLOCK, then yes, it would be good form to use select (or IO::Select), in order to determine whether or not data is present for recv, though this is not technically required, as a recv call will return EAGAIN on a non-blocking socket, if there is no data present to be received.

You also seem to be confusing buffered/unbuffered with blocking/non-blocking. Using send and recv (as well as sysread and syswrite, but not read and print) means that you are using unbuffered IO. Changing the value of autoflush has no effect on recv and send.

Regarding the resizing of your scalar, it should only be resized up to the maximum size specified in your recv call. Why don't you post your code so we can get a better idea of what's happening?

In reply to Re: Re: Re: Re: Re: how do I read from a socket one byte at a time? by MeowChow
in thread how do I read from a socket one byte at a time? by reyjrar

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