From: Robert Klemme <shortcutter@...>
Date: 2009-07-11T16:55:06+09:00
Subject: Re: Quick question on reading from TCPSockets

On 11.07.2009 00:15, Greg Chambers wrote:
> So in my program, I am reading a series of ASCII strings from the
> TCPSocket.  My code is letting everything through just fine.  The
> problem is in the verification of the data.  You see, the point of this
> protocol I am using is I am receiving a series of strings where each
> string has a 4 letter command and then parameters after it.  The command
> and parameters are separated by commas.  So my main worry here is most
> of the examples of TCPSocket networking I've seen use the #read method
> which requires a known amount of bytes to be read and I am worried that
> I will cut one of the commands part way through and cause problems.
> 
> I thought about using #readlines but I wasn't sure how it would treat a
> split message.  If I get a message like
> 
>> GHWD,12,67585,234,4767,234232,757
>> HGYT,0,0
>> PJIY,9876,234,56432,23
> 
> but the full last command was actually
> 
>> PJIY,9876,234,56432,234565,234,7774
> 
> then that messes everything up.  Is there a way to read data delimited
> by a newline and if the last line read does not end with a newline to
> have it placed back in a buffer of some sort to get the next set of
> messages appended to it?

You can simply use #gets or #each (same as #each_line).  Note that #each 
and #each_line accept separators so in case you have something different 
as separator character for records (commands) you can still use that 
approach.  You need to be aware though that the separator character is 
preserved:

socket.each "\n" do |command|
   command.chomp!
   cmd, *args = command.split ','
end


Kind regards

	robert

-- 
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