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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URI::URL(3) User Contributed Perl Documentation URI::URL(3)
NAME
URI::URL - Uniform Resource Locators
SYNOPSIS
$u1 = URI::URL->new($str, $base);
$u2 = $u1->abs;
DESCRIPTION
This module is provided for backwards compatibility with modules that depend on the interface provided by the "URI::URL" class that used to
be distributed with the libwww-perl library.
The following differences exist compared to the "URI" class interface:
o The URI::URL module exports the url() function as an alternate constructor interface.
o The constructor takes an optional $base argument. The "URI::URL" class is a subclass of "URI::WithBase".
o The URI::URL->newlocal class method is the same as URI::file->new_abs.
o URI::URL::strict(1)
o $url->print_on method
o $url->crack method
o $url->full_path: same as ($uri->abs_path || "/")
o $url->netloc: same as $uri->authority
o $url->epath, $url->equery: same as $uri->path, $uri->query
o $url->path and $url->query pass unescaped strings.
o $url->path_components: same as $uri->path_segments (if you don't consider path segment parameters)
o $url->params and $url->eparams methods
o $url->base method. See URI::WithBase.
o $url->abs and $url->rel have an optional $base argument. See URI::WithBase.
o $url->frag: same as $uri->fragment
o $url->keywords: same as $uri->query_keywords
o $url->localpath and friends map to $uri->file.
o $url->address and $url->encoded822addr: same as $uri->to for mailto URI
o $url->groupart method for news URI
o $url->article: same as $uri->message
SEE ALSO
URI, URI::WithBase
COPYRIGHT
Copyright 1998-2000 Gisle Aas.
perl v5.16.2 2012-02-11 URI::URL(3)