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 SUSE
page_util_quote
page_util_quote(n) Parser generator tools page_util_quote(n)
__________________________________________________________________________________________________________________________________________________
NAME
page_util_quote - page character quoting utilities
SYNOPSIS
package require page::util::quote ?0.1?
package require snit
::page::util::quote::unquote char
::page::util::quote::quote'tcl char
::page::util::quote::quote'tclstr char
::page::util::quote::quote'tclcom char
_________________________________________________________________
DESCRIPTION
This package provides a few utility commands to convert characters into various forms.
API
::page::util::quote::unquote char
A character, as stored in an abstract syntax tree by a PEG processor (See the packages grammar::peg::interpreter, grammar::me, and
their relations), i.e. in some quoted form, is converted into the equivalent Tcl character. The character is returned as the result
of the command.
::page::util::quote::quote'tcl char
This command takes a Tcl character (internal representation) and converts it into a string which is accepted by the Tcl parser, will
regenerate the character in question and is 7bit ASCII. The string is returned as the result of this command.
::page::util::quote::quote'tclstr char
This command takes a Tcl character (internal representation) and converts it into a string which is accepted by the Tcl parser and
will generate a human readable representation of the character in question. The string is returned as the result of this command.
The string does not use any unprintable characters. It may use backslash-quoting. High UTF characters are quoted to avoid problems
with the still prevalent ascii terminals. It is assumed that the string will be used in a double-quoted environment.
::page::util::quote::quote'tclcom char
This command takes a Tcl character (internal representation) and converts it into a string which is accepted by the Tcl parser when
used within a Tcl comment. The string is returned as the result of this command.
BUGS, IDEAS, FEEDBACK
This document, will undoubtedly contain bugs and other problems. Please report such in the category page of the Tcllib SF Trackers
[http://sourceforge.net/tracker/?group_id=12883]. Please also report any ideas for enhancements you may have.
KEYWORDS
page, parser generator, quoting, text processing
COPYRIGHT
Copyright (c) 2007 Andreas Kupries <andreas_kupries@users.sourceforge.net>
page 1.0 page_util_quote(n)