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cap-talk, e-lang,<br><br>
I'd like to ask a question of the cap-talk/e-lang lists (please include
cap-talk in any replies). If this issue has been addressed before,
somebody can just point me to the discussion (sorry if I missed
it).<br><br>
One of the strengths of Unix style systems is (I believe) their ability
to "pipe" data among processes, e.g.:<br><br>
ls -l | grep abc | sort > abc-files.txt<br><br>
or perhaps:<br><br>
intty wget <a href="http://.">http://.</a>.. | tr -u '\r' '\n' |<br>
awk '!/^(Location|HTTP|--)/{if($0=="")print;else
printf"%s\r",$0;fflush()}' <br><br>
(something I just grabbed off the Web), etc.<br><br>
In principle of course capability communication systems can provide
similar facilities for "piping" data between running
programs.<br><br>
However, what about "piping" capabilities? With
capabilities as data this seems to me relatively straight forward.
After all, such capabilities are simply data and can - perhaps with
minimal escaping or encoding - just flow through such
"pipes". However, what about in capability as descriptor
systems?<br><br>
Have there ever been such systems (e.g. E, KeyKos/EROS/Coyotos/CapROS,
etc.) that can effectively "pipe" communication streams between
running programs that include capabilities? Perhaps supporting
something like the Unix shell piping syntax, but including capabilities
in the communication for tinker toy connections between working
modules?<br><br>
I'm not aware of any such mechanisms. Perhaps this is just my
ignorance. If there are such I'd like to hear about them.<br><br>
Even in Unix I've heard that open file descriptors can be sent through a
pipe. If that's so, what's the syntax (e.g. as above) look
like? How are the descriptors sent and received specified (by the
sender on sending and by the OS on receiving to the receiver)?<br><br>
This is an area where it has seemed to me that capabilities as data have
some advantages over capabilities as descriptors. If this isn't
true I'd like to hear more about how this aspect of capabilities as
descriptors work (e.g. in reference E or even in Unix with file
descriptors).<br><br>
Thanks for any time to respond.<br>
<x-sigsep><p></x-sigsep>
--Jed
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