From cpan IO::Socket::SSL :

peek(...)

This function has exactly the same syntax as sysread(), and performs nearly the same task (reading data from the socket) but will not advance the read position so that successive calls to peek() with the same arguments will return the same results. This function requires OpenSSL 0.9.6a or later to work.


pending()

This function will let you know how many bytes of data are immediately ready for reading from the socket. This is especially handy if you are doing reads on a blocking socket or just want to know if new data has been sent over the socket.


Update:
Fixed cpan link. ikegami++

In reply to Re: Waiting for input, without sleep by jrsimmon
in thread Waiting for input, without sleep by Trihedralguy

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