10-09-2008
Hello,
Quote:
Its just that I realized now, that neither select() nor O_NONBLOCK ("standard to *nix for alleviating blocking behaviors") work for ordinary files (I mean, who would have thought?)
This is one of the well known *nix gotchas.
Most unix systems programmers have gotten used to it.
Not that it's ideal.
Quote:
By the way, as long as you don't use ordinary files, O_NONBLOCK is not needed. select() does it's job very well even without O_NONBLOCK. On the other hand, if you use select(), O_NONBLOCK is not really needed anymore. Read man select_tut(2) on this.
"
Read or write not blocking on a resource after select returns is not entirely reliable at all times. The select_tut example is it's own best argument against using the non-blocking model imho. Also see:
http://cr.yp.to/unix/nonblock.html
Quote:
You mean I'm trying to optimize too soon? I don't think so, because in this case I try to figure out a good overall structure for the app. This is better done before I write the bulk of code
You are ,imo, optimizing too soon and encountering problems that research may have
ameliorated. Please see if you haven't already:
The C10K problem
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LEARN ABOUT MOJAVE
urn-scheme
uri_urn(n) Tcl Uniform Resource Identifier Management uri_urn(n)
__________________________________________________________________________________________________________________________________________________
NAME
uri_urn - URI utilities, URN scheme
SYNOPSIS
package require Tcl 8.2
package require uri::urn ?1.1.2?
uri::urn::quote url
uri::urn::unquote url
_________________________________________________________________
DESCRIPTION
This package provides two commands to quote and unquote the disallowed characters for url using the urn scheme, registers the scheme with
the package uri, and provides internal helpers which will be automatically used by the commands uri::split and uri::join of package uri to
handle urls using the urn scheme.
COMMANDS
uri::urn::quote url
This command quotes the characters disallowed by the urn scheme (per RFC 2141 sec2.2) in the url and returns the modified url as its
result.
uri::urn::unquote url
This commands performs the reverse of ::uri::urn::quote. It takes an urn url, removes the quoting from all disallowed characters,
and returns the modified urls as its result.
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category uri of
the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883]. Please also report any ideas for enhancements you may have for
either package and/or documentation.
KEYWORDS
rfc 2141, uri, url, urn
CATEGORY
Networking
uri 1.1.2 uri_urn(n)