12-27-2011
How to implement a semaphore with pedestrian pushbutton
Hello,
I need to implement a semaphore in linux c with the following conditions:
1. When there is no pedestrian crossing the street cars can move freely,but if there are any
pedestrians crossing the street, the cars have to wait for pedestrians to pass there.
2. Pedestrians have to wait any car that happens to cross the street, but there are other
pedestrians crossing the street may pass through it simultaneously with other pedestrians.
I think I need two lights synchronized:
1. For pedestrians with a button
2. For Cars
But do not do that by pressing send a signal and an ALARM skip 60 seconds at traffic lights
the cars.
Does anyone can help or give me some pointers on how to do it?
regards
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LEARN ABOUT DEBIAN
net::ldap::filtermatch
Net::LDAP::FilterMatch(3pm) User Contributed Perl Documentation Net::LDAP::FilterMatch(3pm)
NAME
Net::LDAP::FilterMatch - LDAP entry matching
SYNOPSIS
use Net::LDAP::Entry;
use Net::LDAP::Filter;
use Net::LDAP::FilterMatch;
my $entry = new Net::LDAP::Entry;
$entry->dn("cn=dummy entry");
$entry->add (
'cn' => 'dummy entry',
'street' => [ '1 some road','nowhere' ] );
my @filters = (qw/(cn=dummy*)
(ou=*)
(&(cn=dummy*)(street=*road))
(&(cn=dummy*)(!(street=nowhere)))/);
for (@filters) {
my $filter = Net::LDAP::Filter->new($_);
print $_,' : ', $filter->match($entry) ? 'match' : 'no match' ,"
";
}
ABSTRACT
This extension of the class Net::LDAP::Filter provides entry matching functionality on the Perl side.
Given an entry it will tell whether the entry matches the filter object.
It can be used on its own or as part of a Net::LDAP::Server based LDAP server.
METHOD
match ( ENTRY [ ,SCHEMA ] )
Return whether ENTRY matches the filter object. If a schema object is provided, the selection of matching algorithms will be derived
from schema.
In case of error undef is returned.
For approximate matching like (cn~=Schmidt) there are several modules that can be used. By default the following modules will be tried in
this order:
String::Approx
Text::Metaphone
Text::Soundex
If none of these modules is found it will fall back on a simple regexp algorithm.
If you want to specifically use one implementation only, simply do
use Net::LDAP::FilterMatch qw(Text::Soundex);
SEE ALSO
Net::LDAP::Filter
COPYRIGHT
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
AUTHORS
Hans Klunder <hans.klunder@bigfoot.com> Peter Marschall <peter@adpm.de>
perl v5.14.2 2012-01-29 Net::LDAP::FilterMatch(3pm)