Polling on a socket without select()...

[matt robinson]

In article 2065, micky at cunixc.cc.columbia.edu (Micky Liu) writes:
 
>I am writing a program that needs to effect a poll on a udp/ip socket.  I am
>using recvfrom(2) to read data, but I would like it to return immediately if
>there is no data ready...  My SunOS4.x man page says that there is a method
>to make the recvfrom() call return immediately using ioctl(2) to set the
>socket to non-blocking...  I have looked in <sys/ioctl.h> and <sys/sockio.h>
>but have not found any ioctl capable of doing this...

You could set the ioctl to non-blocking without having to check the socket
just once, but if you are looking for the long run, I would suggest using
select to check for data, especially if you are looking to delay for any
length of time, and would like to repeat the procedure.

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