07-21-2011
You mean: you need to implement a
Readers-writer lock mechanism in your program, right?
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Dear Reader,
I'm in a multiprocess environment working with shared mem and semaphores as mutex.. The problem is -- If one of the process hooked up with the semaphore and accessing the shared mem, terminates abruptly ( or got killed ), other process which are in want of the semaphore are... (1 Reply)
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Hi all,
I am using HP 10.20 on A 9000/785. My question is:
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Hi there,
Could someone please confirm which POSIX semaphore routines should be used for a multiprocess (and not multithreaded) environment?
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Hi Friends,
If i execute this command it comes back with 300 lines:
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Hello, first of all I apologize if this thread is not in the correct section of this forum, but this one just seemed the most appropriate.
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Hello,
Iam trying to implement the sleeping barber problem using semaphores and running on UNIX machine. Iam linking it to the thread libraries :
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Hello,
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I am having problem with semaphores. I am trying to protect line where process prints so that every process with print in proper order.This is the code..
#include <stdio.h>
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Hi,
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LEARN ABOUT DEBIAN
msgcache
MSGCACHE(8) System Manager's Manual MSGCACHE(8)
NAME
msgcache - Cache client messages for later pickup by hobbitfetch
SYNOPSIS
msgcache [options]
DESCRIPTION
msgcache implements a Xymon message cache. It is intended for use with clients which cannot deliver their data to the Xymon server in the
normal way. Instead of having the client tools connect to the Xymon server, msgcache runs locally and the client tools then deliver their
data to the msgcache daemon. The msgcache daemon is then polled regularly by the hobbitfetch(8) utility, which collects the client messages
stored by msgcache and forwards them to the Xymon server.
NOTE: When using msgcache, the BBDISP setting for the clients should be BBDISP=127.0.0.1 instead of pointing at the real Xymon server.
RESTRICTIONS
Clients delivering their data to msgcache instead of the real Xymon server will in general not notice this. Specifically, the client con-
figuration data provided by the Xymon server when a client delivers its data is forwarded through the hobbitfetch / msgcache chain, so the
normal centralized client configuration works.
However, other commands which rely on clients communicating directly with the Xymon server will not work. This includes the config and
query commands which clients may use to fetch configuration files and query the Xymon server for a current status.
The download command also does not work with msgcache. This means that the automatic client update facility will not work for clients com-
municating via msgcache.
OPTIONS
--listen=IPADDRESS[:PORT]
Defines the IP-address and portnumber where msgcache listens for incoming connections. By default, msgcache listens for connections
on all network interfaces, port 1984.
--server=IPADDRESS[,IPADDRESS]
Restricts which servers are allowed to pick up the cached messages. By default anyone can contact the msgcache utility and request
all of the cached messages. This option allows only the listed servers to request the cached messages.
--max-age=N
Defines how long cached messages are kept. If the message has not been picked up with N seconds after being delivered to msgcache,
it is silently discarded. Default: N=600 seconds (10 minutes).
--daemon
Run as a daemon, i.e. msgcache will detach from the terminal and run as a background task
--no-daemon
Run as a foreground task. This option must be used when msgcache is started by hobbitlaunch(8) which is the normal way of running
msgcache.
--pidfile=FILENAME
Store the process ID of the msgcache task in FILENAME.
--logfile=FILENAME
Log msgcache output to FILENAME.
--debug
Enable debugging output.
SEE ALSO
hobbitfetch(8), xymon(7)
Xymon Version 4.2.3: 4 Feb 2009 MSGCACHE(8)