Re: passing parameter by reference?

In article <1133224036.299815.300780@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
slebetman@xxxxxxxxx <slebetman@xxxxxxxxx> wrote:
.
.
.
>Actually, yes to a point. Fileevents may not return a complete packet
>and another fileevent on a different socket may trigger. So your
>concerns are valid.
>
>As previous posters have replied, you can use upvar to sort of pass by
>reference.
>
>Personally, for my own web server, I used a global array variable. Just
>use the socket name for the index to the array. For example, you can
>have a global $timeout($channel) to keep track of timeouts and
>$buffer($channel) to buffer incoming data etc.. This way you don't have
>to worry about the second fileevent clobbering your global since each
>fileevent has its own place in the global array.
>

I regard "Fileevents may not return a complete packet and
another fileevent on a different socket may trigger" as
at least doubly confusing:

A. Fileevents are guaranteed to return
a complete packet, in a weak sense
(if the channel is line-delimited,
for example, any fileevent will end
in a newline, 'cept for eof ...);
B. Stock Tcl is singly-threaded, so
a fileevent can trigger only when
the programmer has given control to
the event loop.

I'm fairly sure you know these things, but I suspect naive
readers might misinterpret your description.

I entirely agree that a lot of us index interesting associative
arrays with $channel.
.

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