Search Results

Search found 47805 results on 1913 pages for 'return address'.

Page 198/1913 | < Previous Page | 194 195 196 197 198 199 200 201 202 203 204 205  | Next Page >

  • Google Apps e-mail being rejected from some domains

    - by Paul J. Lucas
    I'm migrating e-mail for my domains to Google Apps' e-mail. Most everything seems to work except e-mail sent to any user at (at least) sonic.net is rejected with a message of the form (where any-address has been substituted for my friend's address): From: Mail Delivery Subsystem <[email protected]> Date: March 11, 2010 10:04:48 AM PST To: [email protected] Subject: Delivery Status Notification (Failure) Delivered-To: [email protected] Received: by 10.229.194.26 with SMTP id dw26cs8717qcb; Thu, 11 Mar 2010 10:04:48 -0800 (PST) Received: by 10.223.68.143 with SMTP id v15mr3841599fai.62.1268330688325; Thu, 11 Mar 2010 10:04:48 -0800 (PST) Received: by 10.223.68.143 with SMTP id v15mr5119424fai.62; Thu, 11 Mar 2010 10:04:48 -0800 (PST) Mime-Version: 1.0 Return-Path: <> X-Failed-Recipients: [email protected] Message-Id: <[email protected]> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Delivery to the following recipient failed permanently: [email protected] Technical details of permanent failure: Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 550 550 5.1.1 <[email protected]>... No such user here (state 13). And here are the headers from the message it bounces back: Received: by 10.101.90.7 with SMTP id s7mr2515885anl.176.1267979929490; Sun, 07 Mar 2010 08:38:49 -0800 (PST) Return-Path: <[email protected]> Received: from [10.0.1.203] (adsl-76-201-171-194.dsl.pltn13.sbcglobal.net [76.201.171.194]) by mx.google.com with ESMTPS id 4sm1046550yxd.70.2010.03.07.08.38.48 (version=TLSv1/SSLv3 cipher=RC4-MD5); Sun, 07 Mar 2010 08:38:49 -0800 (PST) From: "Paul J. Lucas" <[email protected]> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Subject: Some fascinating subject Date: Sun, 7 Mar 2010 08:38:46 -0800 References: <[email protected]> To: [email protected] Message-Id: <[email protected]> Mime-Version: 1.0 (Apple Message framework v1077) X-Mailer: Apple Mail (2.1077) However, I am able to send mail to a user at sonic.net using my old e-mail account. Also, my company uses Google Apps for e-mail and I can send e-mail to a user at sonic.net from my company. The differences between my personal e-mail and my company's are: My company's domain has no SPF record whereas mine does. My company's domain has an A record whereas mine does not. My SPF record initially was as prescribed by Google here. However, this guy claims Google is wrong and gives a fix. I've tried it both ways with no difference. My SPF record is currently: v=spf1 mx include:aspmx.googlemail.com include:_spf.google.com ~all As for the lack of an A record, you wouldn't think that a mail host would care about that so long as mx records are defined. However, the funny thing is that if you look at the error message, why does Google state that the recipient's domain stated that there is "No such user here" for my address? That makes no sense. Of course there is no user having my address at sonic.net. Also, I assume that I just discovered that I can't send mail to users at sonic.net by accident and that there are probably other domains I can't send e-mail to. So... anybody have any idea what's going on? And how I can get mail to users at sonic.net?

    Read the article

  • MacBook can't use internet, but nslookup and ping both work

    - by Joel Coehoorn
    I have a user with a new high-end MacBook Pro that can't use the internet. He can connect to either our wired or wireless network and do things like browse file shares, but can get no further. When I brought the machine in for testing, I found that I could do an nslookup just fine, and I'm able to ping addresses returned by nslookup just fine. I'm even able to bring up web pages by entering the IP address into the address bar directly. However, when I try to ping the domain name rather than the IP address, it just sits there. So apparently I can either do name resolution or communicate with an address, but not both at the same time. Again, these symptoms occur on both the wired and wireless network. Other machines on our network, including a few other Macs, don't have this issue. Any ideas?

    Read the article

  • ifconfig ignores alias on IPv6

    - by Marten Lehmann
    When I add an IPv4 address for the interface eth0:0 with ifconfig, it is created correctly: ifconfig eth0:0 add 192.168.10.10 This can be verified by ifconfig or "ip a". When I add an IPv6 address however, ifconfig seems to ignore the alias of the interface: ifconfig eth0:0 add fc00::2/48 The address fc00::2/48 is added to eth0 then, not to eth0:0, no matter if eth0:0 previously exists with an IPv4 address or not. I'm doing this on CentOS 5 but I guess it is a general behaviour of ifconfig? Am I doing something wrong or is this by intention? I'm using separate aliases for interfaces very often and I hoped to use it for IPv6 as well. Kind regards Marten

    Read the article

  • Salt and hash a password in .NET

    - by Jon Canning
    I endeavoured to follow the CrackStation rules: Salted Password Hashing - Doing it Right    public class SaltedHash     {         public string Hash { get; private set; }         public string Salt { get; private set; }         public SaltedHash(string password)         {             var saltBytes = new byte[32];             new RNGCryptoServiceProvider().GetNonZeroBytes(saltBytes);             Salt = ConvertToBase64String(saltBytes);             var passwordAndSaltBytes = Concat(password, saltBytes);             Hash = ComputeHash(passwordAndSaltBytes);         }         static string ConvertToBase64String(byte[] bytes)         {             return Convert.ToBase64String(bytes);         }         static string ComputeHash(byte[] bytes)         {             return ConvertToBase64String(SHA256.Create().ComputeHash(bytes));         }         static byte[] Concat(string password, byte[] saltBytes)         {             var passwordBytes = Encoding.UTF8.GetBytes(password);             return passwordBytes.Concat(saltBytes).ToArray();         }         public static bool Verify(string salt, string hash, string password)         {             var saltBytes = Convert.FromBase64String(salt);             var passwordAndSaltBytes = Concat(password, saltBytes);             var hashAttempt = ComputeHash(passwordAndSaltBytes);             return hash == hashAttempt;         }     }

    Read the article

  • KVM machine does not start ssh, network is started, used to work

    - by lleto
    have been searching an pulling my hear out for the last 6 hours. I have a virtual machine that has been running fine for the last six months. I was happy ssh'ing into it and it was running a database and some small apps. Tonight ssh stopped working, so I decided to reboot the machine. I now have the following situation: virsh list --all states machine as running I can ping the machine and get a reply When I ssh to the machine I see "ssh: connect to host [myserver] port 22: Connection refused" nmap does not show port 22 as open I have tried to: - reboot the machine once more (no luck) - mount the filesystem and check /etc/ssh/sshd.conf (has not changed since working situation) - install virsh console, however this does not seem to work When I mount the fs directly using losetup the strange thing is that file dates seem to be frozen in /var/log/ around the time of the crash. If I look in /var/run/ I can see an sshd.pid, but the time is 6 hours ago (and numerous reboots). My virsh xml looks like this: <domain type='kvm' id='21'> <name>myserver</name> <uuid>09678c8d-a99b-1d18-a7af-88d027cc8f93</uuid> <memory>1048576</memory> <currentMemory>1048576</currentMemory> <vcpu>1</vcpu> <os> <type arch='x86_64' machine='pc-1.0'>hvm</type> <boot dev='hd'/> </os> <features> <acpi/> </features> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>destroy</on_crash> <devices> <emulator>/usr/bin/kvm</emulator> <disk type='file' device='disk'> <driver name='qemu' type='raw'/> <source file='/dev/disk01/myserver'/> <target dev='hda' bus='ide'/> <alias name='ide0-0-0'/> <address type='drive' controller='0' bus='0' unit='0'/> </disk> <controller type='ide' index='0'> <alias name='ide0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> </controller> <interface type='bridge'> <mac address='52:54:00:e3:13:86'/> <source bridge='br0'/> <target dev='vnet0'/> <model type='virtio'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> <serial type='pty'> <source path='/dev/pts/1'/> <target port='0'/> <alias name='serial0'/> </serial> <console type='pty' tty='/dev/pts/1'> <source path='/dev/pts/1'/> <target type='serial' port='0'/> <alias name='serial0'/> </console> <input type='mouse' bus='ps2'/> <graphics type='vnc' port='5900' autoport='yes' listen='127.0.0.1'> <listen type='address' address='127.0.0.1'/> </graphics> <video> <model type='cirrus' vram='9216' heads='1'/> <alias name='video0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </video> <memballoon model='virtio'> <alias name='balloon0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </memballoon> </devices> <seclabel type='dynamic' model='apparmor' relabel='yes'> <label>libvirt-09678c8d-a99b-1d18-a7af-88d027cc8f93</label> <imagelabel>libvirt-09678c8d-a99b-1d18-a7af-88d027cc8f93</imagelabel> </seclabel> </domain> I'm sort of lost as to where I can look to get the machine up and running again. On the same instance of kvm I have another server running which is working fine. Both are Ubuntu 12.04. All help is welcome....

    Read the article

  • what is ip 10.1.1.130 to which seems monitored by NT Kernel & System process on Windows 7?

    - by EndangeringSpecies
    I used netstat to see what is happening with network connections, and I see this weird ip address somehow listed together with PID 4 "NT Kernel & System", whatever that might be. Netstat describes it as a "local address" and there is no "foreign address" involved (btw, what are local and foreign addresses anyway?) In the column to the right there is neither "listening" nor "established" record, so no record at all there.

    Read the article

  • How to configure Exchange Server with AutoReply that sends the reply only once?

    - by Abel
    If you configure Exchange Server 2007 for auto-reply on a public address, and the reply is sent to an address that also has auto-reply or out-of-office-auto-reply, then Exchange Server will receive a new message, same from-address, and will again send an auto-reply. This can go on forever and can potentially lead to a DoS situation. How can I prevent multiple sending of auto-reply to the same address, preferably in a given timeframe (to prevent legitimate multiple mails to be treated incorrectly), using Exchange Server 2007? Our XS hosting provider says it cannot be done, but that strikes me as odd.

    Read the article

  • How to balance the root domain using NS records?

    - by Patrick McCurley
    I have two load balancers that balance incoming traffic across multiple data centers. These work fine. I can test them out by doing an 'nslookup mydomain.com xIP' I have now taken out DNS services with DYN.com to allow me to manage the DNS Zone file so that typing mydomain.com will ask my load balancers what the IP address is to resolve. Step 1 : the NS record for www. I set up A records (glue) for ns1 & ns2, then the corresponding NS record to delegate the DNS lookup to the balancers instead of DYN.com's nameservers. ns1.mydomain.com A [ip address of load balancer 1] ns2.mydomain.com A [ip address of load balancer 1] www.mydomain.com NS ns1.mydomain.com www.mydomain.com NS ns2.mydomain.com All is well - when I type www.mydomain.com, the requests get delegated to my load balancers who provide the IP address of the endpoint and the connect is made successfully. Step 2 : the NS record for root. This is where I run into problems. I need customers to be able to type 'mydomain.com' (without the www) and ALSO get delegated to the load balancers for the IP address. However - of the research I have done, and through the DYN control panel, it seems to be not allowed to provide an NS record for the root - as this overrides the default NS servers. How can i delegate both the root, and the www. to my load balancers?

    Read the article

  • How can I forward ALL traffic over a site-to-site VPN on Cisco ASA?

    - by Scott Clements
    Hi There, I currently have two Cisco ASA 5100 routers. They are at different physical sites and are configured with a site-to-site VPN which is active and working. I can communicate with the subnets on either site from the other and both are connected to the internet, however I need to ensure that all the traffic at my remote site goes through this VPN to my site here. I know that the web traffic is doing so as a "tracert" confirms this, but I need to ensure that all other network traffic is being directed over this VPN to my network here. Here is my config for the ASA router at my remote site: hostname ciscoasa domain-name xxxxx enable password 78rl4MkMED8xiJ3g encrypted names ! interface Ethernet0/0 nameif NIACEDC security-level 100 ip address x.x.x.x 255.255.255.0 ! interface Ethernet0/1 description External Janet Connection nameif JANET security-level 0 ip address x.x.x.x 255.255.255.248 ! interface Ethernet0/2 shutdown no nameif security-level 100 no ip address ! interface Ethernet0/3 shutdown no nameif security-level 100 ip address dhcp setroute ! interface Management0/0 nameif management security-level 100 ip address 192.168.100.1 255.255.255.0 management-only ! passwd 2KFQnbNIdI.2KYOU encrypted ftp mode passive clock timezone GMT/BST 0 clock summer-time GMT/BDT recurring last Sun Mar 1:00 last Sun Oct 2:00 dns domain-lookup NIACEDC dns server-group DefaultDNS name-server 154.32.105.18 name-server 154.32.107.18 domain-name XXXX same-security-traffic permit inter-interface same-security-traffic permit intra-interface access-list ren_access_in extended permit ip any any access-list ren_access_in extended permit tcp any any access-list ren_nat0_outbound extended permit ip 192.168.6.0 255.255.255.0 192.168.3.0 255.255.255.0 access-list NIACEDC_nat0_outbound extended permit ip 192.168.12.0 255.255.255.0 192.168.3.0 255.255.255.0 access-list JANET_20_cryptomap extended permit ip 192.168.12.0 255.255.255.0 192.168.3.0 255.255.255.0 access-list NIACEDC_access_in extended permit ip any any access-list NIACEDC_access_in extended permit tcp any any access-list JANET_access_out extended permit ip any any access-list NIACEDC_access_out extended permit ip any any pager lines 24 logging enable logging asdm informational mtu NIACEDC 1500 mtu JANET 1500 mtu management 1500 icmp unreachable rate-limit 1 burst-size 1 asdm image disk0:/asdm-522.bin no asdm history enable arp timeout 14400 nat-control global (NIACEDC) 1 interface global (JANET) 1 interface nat (NIACEDC) 0 access-list NIACEDC_nat0_outbound nat (NIACEDC) 1 192.168.12.0 255.255.255.0 access-group NIACEDC_access_in in interface NIACEDC access-group NIACEDC_access_out out interface NIACEDC access-group JANET_access_out out interface JANET route JANET 0.0.0.0 0.0.0.0 194.82.121.82 1 route JANET 0.0.0.0 0.0.0.0 192.168.3.248 tunneled timeout xlate 3:00:00 timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02 timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00 timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00 timeout uauth 0:05:00 absolute http server enable http 192.168.12.0 255.255.255.0 NIACEDC http 192.168.100.0 255.255.255.0 management http 192.168.9.0 255.255.255.0 NIACEDC no snmp-server location no snmp-server contact snmp-server enable traps snmp authentication linkup linkdown coldstart crypto ipsec transform-set ESP-3DES-SHA esp-3des esp-sha-hmac crypto ipsec transform-set ESP-AES-256-SHA esp-aes-256 esp-sha-hmac crypto map JANET_map 20 match address JANET_20_cryptomap crypto map JANET_map 20 set pfs crypto map JANET_map 20 set peer X.X.X.X crypto map JANET_map 20 set transform-set ESP-AES-256-SHA crypto map JANET_map interface JANET crypto isakmp enable JANET crypto isakmp policy 10 authentication pre-share encryption aes-256 hash sha group 2 lifetime 86400 crypto isakmp policy 30 authentication pre-share encryption 3des hash sha group 2 lifetime 86400 crypto isakmp policy 50 authentication pre-share encryption aes-256 hash sha group 5 lifetime 86400 tunnel-group X.X.X.X type ipsec-l2l tunnel-group X.X.X.X ipsec-attributes pre-shared-key * telnet timeout 5 ssh timeout 5 console timeout 0 dhcpd address 192.168.100.2-192.168.100.254 management dhcpd enable management ! ! class-map inspection_default match default-inspection-traffic ! ! policy-map type inspect dns preset_dns_map parameters message-length maximum 512 policy-map global_policy class inspection_default inspect dns preset_dns_map inspect ftp inspect h323 h225 inspect h323 ras inspect rsh inspect rtsp inspect esmtp inspect sqlnet inspect skinny inspect sunrpc inspect xdmcp inspect sip inspect netbios inspect tftp inspect http ! service-policy global_policy global prompt hostname context no asdm history enable Thanks in advance, Scott

    Read the article

  • Of C# Iterators and Performance

    - by James Michael Hare
    Some of you reading this will be wondering, "what is an iterator" and think I'm locked in the world of C++.  Nope, I'm talking C# iterators.  No, not enumerators, iterators.   So, for those of you who do not know what iterators are in C#, I will explain it in summary, and for those of you who know what iterators are but are curious of the performance impacts, I will explore that as well.   Iterators have been around for a bit now, and there are still a bunch of people who don't know what they are or what they do.  I don't know how many times at work I've had a code review on my code and have someone ask me, "what's that yield word do?"   Basically, this post came to me as I was writing some extension methods to extend IEnumerable<T> -- I'll post some of the fun ones in a later post.  Since I was filtering the resulting list down, I was using the standard C# iterator concept; but that got me wondering: what are the performance implications of using an iterator versus returning a new enumeration?   So, to begin, let's look at a couple of methods.  This is a new (albeit contrived) method called Every(...).  The goal of this method is to access and enumeration and return every nth item in the enumeration (including the first).  So Every(2) would return items 0, 2, 4, 6, etc.   Now, if you wanted to write this in the traditional way, you may come up with something like this:       public static IEnumerable<T> Every<T>(this IEnumerable<T> list, int interval)     {         List<T> newList = new List<T>();         int count = 0;           foreach (var i in list)         {             if ((count++ % interval) == 0)             {                 newList.Add(i);             }         }           return newList;     }     So basically this method takes any IEnumerable<T> and returns a new IEnumerable<T> that contains every nth item.  Pretty straight forward.   The problem?  Well, Every<T>(...) will construct a list containing every nth item whether or not you care.  What happens if you were searching this result for a certain item and find that item after five tries?  You would have generated the rest of the list for nothing.   Enter iterators.  This C# construct uses the yield keyword to effectively defer evaluation of the next item until it is asked for.  This can be very handy if the evaluation itself is expensive or if there's a fair chance you'll never want to fully evaluate a list.   We see this all the time in Linq, where many expressions are chained together to do complex processing on a list.  This would be very expensive if each of these expressions evaluated their entire possible result set on call.    Let's look at the same example function, this time using an iterator:       public static IEnumerable<T> Every<T>(this IEnumerable<T> list, int interval)     {         int count = 0;         foreach (var i in list)         {             if ((count++ % interval) == 0)             {                 yield return i;             }         }     }   Notice it does not create a new return value explicitly, the only evidence of a return is the "yield return" statement.  What this means is that when an item is requested from the enumeration, it will enter this method and evaluate until it either hits a yield return (in which case that item is returned) or until it exits the method or hits a yield break (in which case the iteration ends.   Behind the scenes, this is all done with a class that the CLR creates behind the scenes that keeps track of the state of the iteration, so that every time the next item is asked for, it finds that item and then updates the current position so it knows where to start at next time.   It doesn't seem like a big deal, does it?  But keep in mind the key point here: it only returns items as they are requested. Thus if there's a good chance you will only process a portion of the return list and/or if the evaluation of each item is expensive, an iterator may be of benefit.   This is especially true if you intend your methods to be chainable similar to the way Linq methods can be chained.    For example, perhaps you have a List<int> and you want to take every tenth one until you find one greater than 10.  We could write that as:       List<int> someList = new List<int>();         // fill list here         someList.Every(10).TakeWhile(i => i <= 10);     Now is the difference more apparent?  If we use the first form of Every that makes a copy of the list.  It's going to copy the entire list whether we will need those items or not, that can be costly!    With the iterator version, however, it will only take items from the list until it finds one that is > 10, at which point no further items in the list are evaluated.   So, sounds neat eh?  But what's the cost is what you're probably wondering.  So I ran some tests using the two forms of Every above on lists varying from 5 to 500,000 integers and tried various things.    Now, iteration isn't free.  If you are more likely than not to iterate the entire collection every time, iterator has some very slight overhead:   Copy vs Iterator on 100% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 5 Copy 5 5 5 Iterator 5 50 50 Copy 28 50 50 Iterator 27 500 500 Copy 227 500 500 Iterator 247 5000 5000 Copy 2266 5000 5000 Iterator 2444 50,000 50,000 Copy 24,443 50,000 50,000 Iterator 24,719 500,000 500,000 Copy 250,024 500,000 500,000 Iterator 251,521   Notice that when iterating over the entire produced list, the times for the iterator are a little better for smaller lists, then getting just a slight bit worse for larger lists.  In reality, given the number of items and iterations, the result is near negligible, but just to show that iterators come at a price.  However, it should also be noted that the form of Every that returns a copy will have a left-over collection to garbage collect.   However, if we only partially evaluate less and less through the list, the savings start to show and make it well worth the overhead.  Let's look at what happens if you stop looking after 80% of the list:   Copy vs Iterator on 80% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 4 Copy 5 5 4 Iterator 5 50 40 Copy 27 50 40 Iterator 23 500 400 Copy 215 500 400 Iterator 200 5000 4000 Copy 2099 5000 4000 Iterator 1962 50,000 40,000 Copy 22,385 50,000 40,000 Iterator 19,599 500,000 400,000 Copy 236,427 500,000 400,000 Iterator 196,010       Notice that the iterator form is now operating quite a bit faster.  But the savings really add up if you stop on average at 50% (which most searches would typically do):     Copy vs Iterator on 50% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 2 Copy 5 5 2 Iterator 4 50 25 Copy 25 50 25 Iterator 16 500 250 Copy 188 500 250 Iterator 126 5000 2500 Copy 1854 5000 2500 Iterator 1226 50,000 25,000 Copy 19,839 50,000 25,000 Iterator 12,233 500,000 250,000 Copy 208,667 500,000 250,000 Iterator 122,336   Now we see that if we only expect to go on average 50% into the results, we tend to shave off around 40% of the time.  And this is only for one level deep.  If we are using this in a chain of query expressions it only adds to the savings.   So my recommendation?  If you have a resonable expectation that someone may only want to partially consume your enumerable result, I would always tend to favor an iterator.  The cost if they iterate the whole thing does not add much at all -- and if they consume only partially, you reap some really good performance gains.   Next time I'll discuss some of my favorite extensions I've created to make development life a little easier and maintainability a little better.

    Read the article

  • VPN networking issue

    - by DuncanDavies
    I have 2 servers hosted in the cloud. One an application server, one a VPN server, both running Win2008. Both have a local IP address assigned by DHCP in different network subnets, 10.227.55.0 (VPN) and 10.231.5.0 (App Server). These servers can ping each other. My VPN client connects in to the VPN server (using a L2TP connection on a Win7 client). It is assigned an IP Address from the VPN server's static pool (the VPN server takes 192.168.100.1, the client is given 192.168.100.2). The client can ping both the 192.168.100.1 address of the VPN server, and its 'local' IP address (10.227.55.X). What the client can't do is ping the App Server. How can I configure routing so that my client can access the App Server, without hard-coding any of the DHCP IP addresses anywhere? thanks Duncan

    Read the article

  • Web Application : How to upload multiple images at a time

    - by SAMIR BHOGAYTA
    //First add image control into the web form how many you want to upload images at a time //Add one button //Write the below code into the button_click event if (FileUpload1.HasFile) { string imagefile = FileUpload1.FileName; if (CheckFileType(imagefile) == true) { Random rndob = new Random(); int db = rndob.Next(1, 100); filename = System.IO.Path.GetFileNameWithoutExtension(imagefile) + db.ToString() + System.IO.Path.GetExtension(imagefile); String FilePath = "images/" + filename; FileUpload1.SaveAs(Server.MapPath(FilePath)); objimg.ImageName = filename; Image1(); if (Session["imagecount"].ToString() == "1") { Img1.ImageUrl = FilePath; ViewState["img1"] = FilePath; } else if (Session["imagecount"].ToString() == "2") { Img1.ImageUrl = ViewState["img1"].ToString(); Img2.ImageUrl = FilePath; ViewState["img2"] = FilePath; } else if (Session["imagecount"].ToString() == "3") { Img1.ImageUrl = ViewState["img1"].ToString(); Img2.ImageUrl = ViewState["img2"].ToString(); Img3.ImageUrl = FilePath; ViewState["img3"] = FilePath; } else if (Session["imagecount"].ToString() == "4") { Img1.ImageUrl = ViewState["img1"].ToString(); Img2.ImageUrl = ViewState["img2"].ToString(); Img3.ImageUrl = ViewState["img3"].ToString(); Img4.ImageUrl = FilePath; ViewState["img4"] = FilePath; } else if (Session["imagecount"].ToString() == "5") { Img1.ImageUrl = ViewState["img1"].ToString(); Img2.ImageUrl = ViewState["img2"].ToString(); Img3.ImageUrl = ViewState["img3"].ToString(); Img4.ImageUrl = ViewState["img4"].ToString(); Img5.ImageUrl = FilePath; ViewState["img5"] = FilePath; } } } //execption handling else { lblErrMsg.Visible = true; lblErrMsg.Text = ""; lblErrMsg.Text = "please select a file"; } } //if file extension belongs to these list then only allowed public bool CheckFileType(string filename) { string ext; ext = System.IO.Path.GetExtension(filename); switch (ext.ToLower()) { case ".gif": return true; case ".jpeg": return true; case ".jpg": return true; case ".bmp": return true; case ".png": return true; default: return false; } }

    Read the article

  • Mac Websharing Off but Process Running

    - by benedict_w
    I have my mac setup to use php / mysql / apache via macports. Recently it has gone a bit pear shaped: it seems that the local mac versions of apache and mysql are running blocking the macports services: (48)Address already in use: make_sock: could not bind to address [::]:80 (48)Address already in use: make_sock: could not bind to address [::]:443 Web sharing in System preferences is off - How can I properly disable it? I tried turning it on an off again in System Preferences but it would not changed from off to on. Also if I kill the process it starts running again.

    Read the article

  • getting Internet connection sharing working in a slightly more complicated configuration

    - by tirichitirca t
    I have the following configuration: Computer A - Mac OSX 10.8.4, wireless & wired adapters Computer B - Windows 7 (64 bit), wireless & wired adapters, has internet connection via the wired adapter (ethernet) d-link wired/wireless router. Problem to solve: Connect from computer A to the internet through the wired connection of computer B. I tried the following: I set up a local network between A and B using the d-link router. The configuration is this: D-link router - 192.168.0.1 A - wired connection to the d-link router, static 192.168.0.101 (I could have used the wireless but I preferred the wired connection) B - wireless connection to the d-link router DHCP 192.168.0.102 (but I made sure it always gets the same address) B - wired connection to the internet using some address that begins with 10.x.y.z. In this configuration A can see B. I enabled ICS on the wired adapter of B. I set up the Gateway of A to point to B and DNS servers to point to the DNS servers specified for the 10.x.y.z address. It doesn't work, A goes only as far as B. It can ping the 10.x.y.z address of B though. I then found this article: http://terrybritton.com/windows-internet-connection-sharing-ics-not-working-with-linux-bridging-is-the-solution-916/. Terry is suggesting that a bridge should be defined on B between the two connections. I tried that but basically computer B is screwed as soon as I create the bridge. It can't connect to the internet anymore. It is as if the network bridge seems to think the traffic to the internet should go from the wired connection to the wireless and not the other way around. The other thing that puzzles me is the router itself. In general the router needs an internet address. In a normal configuration it is the router that gets the ip address and the internet traffic goes through the router. In my case I am not interested in that. So, any suggestions to get this working? I wouldn't shy away from using a commercial software but I would think windows 7 should allow me to do it. Thanks

    Read the article

  • Mac OS X Server 10.6.6 DNS not responding properly, get a "Truncated, retrying in TCP mode" for subdomain

    - by Eric Arseneau
    If I do an nslookup on youtube.com, no problem, if I do one with www.youtube.com, failure. See details below. [~] nslookup youtube.com Server: 192.168.1.1 Address: 192.168.1.1#53 Non-authoritative answer: Name: youtube.com Address: 74.125.127.93 Name: youtube.com Address: 74.125.47.93 Name: youtube.com Address: 74.125.95.93 [~] nslookup www.youtube.com ;; Truncated, retrying in TCP mode. ;; Connection to 192.168.1.1#53(192.168.1.1) for www.youtube.com failed: connection refused. If I do the same from a Windows machine its fine, its when I do it from a Mac workstation that I get the issue. I have rebooted, both server and workstation, I did a changeip, but nothing is working. Any recommendations?

    Read the article

  • String.IsNullOrWhiteSpace

    - by Scott Dorman
    An empty string is different than an unassigned string variable (which is null), and is a string containing no characters between the quotes (""). The .NET Framework provides String.Empty to represent an empty string, and there is no practical difference between ("") and String.Empty. One of the most common string comparisons to perform is to determine if a string variable is equal to an empty string. The fastest and simplest way to determine if a string is empty is to test if the Length property is equal to 0. However, since strings are reference types it is possible for a string variable to be null, which would result in a runtime error when you tried to access the Length property. Since testing to determine if a string is empty is such a common occurrence, the .NET Framework provides the static method String.IsNullOrEmpty method: public static bool IsNullOrEmpty(string value) { if (value != null) { return (value.Length == 0); }   return true; } It is also very common to determine if a string is empty and contains more than just whitespace characters. For example, String.IsNullOrEmpty("   ") would return false, since this string is actually made up of three whitespace characters. In some cases, this may be acceptable, but in many others it is not. TO help simplify testing this scenario, the .NET Framework 4 introduces the String.IsNullOrWhiteSpace method: public static bool IsNullOrWhiteSpace(string value) { if (value != null) { for (int i = 0; i < value.Length; i++) { if (!char.IsWhiteSpace(value[i])) { return false; } } } return true; }   Using either String.IsNullOrEmpty or String.IsNullOrWhiteSpace helps ensure correctness, readability, and consistency, so they should be used in all situations where you need to determine if a string is null, empty, or contains only whitespace characters. Technorati Tags: .NET,C# 4

    Read the article

  • Does not recognize usb sticks and drives

    - by Peter
    When connecting any usb stick to my thinkpad ubuntu 10.10 does not recognize them. I don't see anything on the desktop. the output of "dmesg | tail -n10" gives me: [ 1965.696388] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1965.884537] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1966.072503] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1966.260349] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1966.506227] usb 1-1: new high speed USB device using ehci_hcd and address 9 [ 1966.572375] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1966.760379] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1966.948358] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1967.136335] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 1967.325423] hub 1-0:1.0: unable to enumerate USB device on port 1 When connecting my usb scanner to the same port: [ 2008.480135] usb 1-1: new high speed USB device using ehci_hcd and address 65 [ 2008.548389] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 2008.736786] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 2008.924379] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 2009.112348] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 2009.300443] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 2009.488536] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 2009.732180] usb 1-1: new high speed USB device using ehci_hcd and address 71 [ 2014.796299] hub 1-0:1.0: unable to enumerate USB device on port 1 [ 2018.000128] usb 2-1: new full speed USB device using uhci_hcd and address 3 And ubuntu 10.10 recognizes that scanner. So: What can i do to see my usb stick? BTW: on my other Thinkpad running fedora 14 it works perfectly... Cheers -Peter

    Read the article

  • USB keyboard stopped working in Ubuntu with error -71

    - by tapan
    I have a usb keyboard which was working perfectly till now (about a year since i have been regularly using ubuntu). It suddenly stopped working. It stopped working when I connected a USB HDD. Now the keyboard works randomly .. working for a while and then stops working for a longer time. Here is the dmesg output : [ 705.817076] usb 5-1: device not accepting address 8, error -71 [ 705.928032] usb 5-1: new low speed USB device using uhci_hcd and address 9 [ 706.336060] usb 5-1: device not accepting address 9, error -71 [ 706.448055] usb 5-1: new low speed USB device using uhci_hcd and address 10 [ 706.568044] usb 5-1: device descriptor read/64, error -71 [ 706.792049] usb 5-1: device descriptor read/64, error -71 [ 707.008060] usb 5-1: new low speed USB device using uhci_hcd and address 11 [ 707.128041] usb 5-1: device descriptor read/64, error -71 [ 707.352052] usb 5-1: device descriptor read/64, error -71 [ 707.456068] hub 5-0:1.0: unable to enumerate USB device on port 1 Based on the suggestions here i tried the following two things: echo -1 > /sys/module/usbcore/parameters/autosuspend echo Y > /sys/module/usbcore/parameters/old_scheme_first However, i am still facing the same problem. Can anyone help me out with this ? I'm using Ubuntu 10.04 Lucid Lynx.

    Read the article

  • XNA 3D model collision is inaccurate

    - by Daniel Lopez
    I am creating a classic game in 3d that deals with asteriods and you have to shoot them and avoid being hit from them. I can generate the asteroids just fine and the ship can shoot bullets just fine. But the asteroids always hit the ship even it doesn't look they are even close. I know 2D collision very well but not 3D so can someone please shed some light to my problem. Thanks in advance. Code For ModelRenderer: using System; using System.Collections.Generic; using System.Linq; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.GamerServices; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; using Microsoft.Xna.Framework.Media; namespace _3D_Asteroids { class ModelRenderer { private float aspectratio; private Model model; private Vector3 camerapos; private Vector3 modelpos; private Matrix rotationy; float radiansy = 0; private bool isalive; public ModelRenderer(Model m, float AspectRatio, Vector3 initial_pos, Vector3 initialcamerapos) { isalive = true; model = m; if (model.Meshes.Count == 0) { throw new Exception("Invalid model because it contains zero meshes!"); } modelpos = initial_pos; camerapos = initialcamerapos; aspectratio = AspectRatio; return; } public float RadiusOfSphere { get { return model.Meshes[0].BoundingSphere.Radius; } } public BoundingBox BoxBounds { get { return BoundingBox.CreateFromSphere(model.Meshes[0].BoundingSphere); } } public BoundingSphere SphereBounds { get { return model.Meshes[0].BoundingSphere; } } public Vector3 CameraPosition { set { camerapos = value; } get { return camerapos; } } public bool IsAlive { get { return isalive; } } public Vector3 ModelPosition { set { modelpos = value; } get { return modelpos; } } public void RotateY(float radians) { radiansy += radians; rotationy = Matrix.CreateRotationY(radiansy); } public Matrix RotationY { set { rotationy = value; } get { return rotationy; } } public float AspectRatio { set { aspectratio = value; } get { return aspectratio; } } public void Kill() { isalive = false; } public void Draw(float scale) { Matrix world; if (rotationy == new Matrix(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)) { world = Matrix.CreateScale(scale) * Matrix.CreateTranslation(modelpos); } else { world = rotationy * Matrix.CreateScale(scale) * Matrix.CreateTranslation(modelpos); } Matrix view = Matrix.CreateLookAt(camerapos, Vector3.Zero, Vector3.Up); Matrix projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(45.0f), this.AspectRatio, 1f, 100000f); foreach (ModelMesh mesh in model.Meshes) { foreach (BasicEffect effect in mesh.Effects) { effect.World = world; effect.View = view; effect.Projection = projection; } mesh.Draw(); } } public void Draw() { Matrix world; if (rotationy == new Matrix(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)) { world = Matrix.CreateTranslation(modelpos); } else { world = rotationy * Matrix.CreateTranslation(modelpos); } Matrix view = Matrix.CreateLookAt(camerapos, Vector3.Zero, Vector3.Up); Matrix projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(45.0f), this.AspectRatio, 1f, 100000f); foreach (ModelMesh mesh in model.Meshes) { foreach (BasicEffect effect in mesh.Effects) { effect.World = world; effect.View = view; effect.Projection = projection; } mesh.Draw(); } } } Code For Game1: using System; using System.Collections.Generic; using System.Linq; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.GamerServices; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; using Microsoft.Xna.Framework.Media; namespace _3D_Asteroids { /// <summary> /// This is the main type for your game /// </summary> public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; int score = 0, lives = 5; SpriteBatch spriteBatch; GameState gstate = GameState.OnMenuScreen; Menu menu = new Menu(Color.Yellow, Color.White); SpriteFont font; Texture2D background; ModelRenderer ship; Model b, a; List<ModelRenderer> bullets = new List<ModelRenderer>(); List<ModelRenderer> asteriods = new List<ModelRenderer>(); float time = 0.0f; int framecount = 0; SoundEffect effect; public Game1() { graphics = new GraphicsDeviceManager(this); graphics.PreferredBackBufferWidth = 1280; graphics.PreferredBackBufferHeight = 796; graphics.ApplyChanges(); Content.RootDirectory = "Content"; } /// <summary> /// Allows the game to perform any initialization it needs to before starting to run. /// This is where it can query for any required services and load any non-graphic /// related content. Calling base.Initialize will enumerate through any components /// and initialize them as well. /// </summary> protected override void Initialize() { // TODO: Add your initialization logic here base.Initialize(); } /// <summary> /// LoadContent will be called once per game and is the place to load /// all of your content. /// </summary> protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); font = Content.Load<SpriteFont>("Fonts\\Lucida Console"); background = Content.Load<Texture2D>("Textures\\B1_stars"); Model p1 = Content.Load<Model>("Models\\p1_wedge"); b = Content.Load<Model>("Models\\pea_proj"); a = Content.Load<Model>("Models\\asteroid1"); effect = Content.Load<SoundEffect>("Audio\\tx0_fire1"); ship = new ModelRenderer(p1, GraphicsDevice.Viewport.AspectRatio, new Vector3(0, 0, 0), new Vector3(0, 0, 9000)); } /// <summary> /// UnloadContent will be called once per game and is the place to unload /// all content. /// </summary> protected override void UnloadContent() { } /// <summary> /// Allows the game to run logic such as updating the world, /// checking for collisions, gathering input, and playing audio. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Update(GameTime gameTime) { KeyboardState state = Keyboard.GetState(PlayerIndex.One); switch (gstate) { case GameState.OnMenuScreen: { if (state.IsKeyDown(Keys.Enter)) { switch (menu.SelectedChoice) { case MenuChoices.Play: { gstate = GameState.GameStarted; break; } case MenuChoices.Exit: { this.Exit(); break; } } } if (state.IsKeyDown(Keys.Down)) { menu.MoveSelectedMenuChoiceDown(gameTime); } else if(state.IsKeyDown(Keys.Up)) { menu.MoveSelectedMenuChoiceUp(gameTime); } else { menu.KeysReleased(); } break; } case GameState.GameStarted: { foreach (ModelRenderer bullet in bullets) { if (bullet.ModelPosition.X < (ship.ModelPosition.X + 4000) && bullet.ModelPosition.Z < (ship.ModelPosition.X + 4000) && bullet.ModelPosition.X > (ship.ModelPosition.Z - 4000) && bullet.ModelPosition.Z > (ship.ModelPosition.Z - 4000)) { bullet.ModelPosition += (bullet.RotationY.Forward * 120); } else if (collidedwithasteriod(bullet)) { bullet.Kill(); } else { bullet.Kill(); } } foreach (ModelRenderer asteroid in asteriods) { if (ship.SphereBounds.Intersects(asteroid.BoxBounds)) { lives -= 1; asteroid.Kill(); // This always hits no matter where the ship goes. } else { asteroid.ModelPosition -= (asteroid.RotationY.Forward * 50); } } for (int index = 0; index < asteriods.Count; index++) { if (asteriods[index].IsAlive == false) { asteriods.RemoveAt(index); } } for (int index = 0; index < bullets.Count; index++) { if (bullets[index].IsAlive == false) { bullets.RemoveAt(index); } } if (state.IsKeyDown(Keys.Left)) { ship.RotateY(0.1f); if (state.IsKeyDown(Keys.Space)) { if (time < 17) { firebullet(); //effect.Play(); } } else { time = 0; } } else if (state.IsKeyDown(Keys.Right)) { ship.RotateY(-0.1f); if (state.IsKeyDown(Keys.Space)) { if (time < 17) { firebullet(); //effect.Play(); } } else { time = 0; } } else if (state.IsKeyDown(Keys.Up)) { ship.ModelPosition += (ship.RotationY.Forward * 50); if (state.IsKeyDown(Keys.Space)) { if (time < 17) { firebullet(); //effect.Play(); } } else { time = 0; } } else if (state.IsKeyDown(Keys.Space)) { time += gameTime.ElapsedGameTime.Milliseconds; if (time < 17) { firebullet(); //effect.Play(); } } else { time = 0.0f; } if ((framecount % 60) == 0) { createasteroid(); framecount = 0; } framecount++; break; } } base.Update(gameTime); } void firebullet() { if (bullets.Count < 3) { ModelRenderer bullet = new ModelRenderer(b, GraphicsDevice.Viewport.AspectRatio, ship.ModelPosition, new Vector3(0, 0, 9000)); bullet.RotationY = ship.RotationY; bullets.Add(bullet); } } void createasteroid() { if (asteriods.Count < 2) { Random random = new Random(); float z = random.Next(-13000, -11000); float x = random.Next(-9000, -8000); Random random2 = new Random(); int degrees = random.Next(0, 45); float radians = MathHelper.ToRadians(degrees); ModelRenderer asteroid = new ModelRenderer(a, GraphicsDevice.Viewport.AspectRatio, new Vector3(x, 0, z), new Vector3(0,0, 9000)); asteroid.RotateY(radians); asteriods.Add(asteroid); } } /// <summary> /// This is called when the game should draw itself. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); switch (gstate) { case GameState.OnMenuScreen: { spriteBatch.Begin(); spriteBatch.Draw(background, Vector2.Zero, Color.White); menu.DrawMenu(ref spriteBatch, font, new Vector2(GraphicsDevice.Viewport.Width / 2, GraphicsDevice.Viewport.Height / 2) - new Vector2(50f), 100f); spriteBatch.End(); break; } case GameState.GameStarted: { spriteBatch.Begin(); spriteBatch.Draw(background, Vector2.Zero, Color.White); spriteBatch.DrawString(font, "Score: " + score.ToString() + "\nLives: " + lives.ToString(), Vector2.Zero, Color.White); spriteBatch.End(); ship.Draw(); foreach (ModelRenderer bullet in bullets) { bullet.Draw(); } foreach (ModelRenderer asteroid in asteriods) { asteroid.Draw(0.1f); } break; } } base.Draw(gameTime); } bool collidedwithasteriod(ModelRenderer bullet) { foreach (ModelRenderer asteroid in asteriods) { if (bullet.SphereBounds.Intersects(asteroid.BoxBounds)) { score += 10; asteroid.Kill(); return true; } } return false; } } } }

    Read the article

  • C#: LINQ vs foreach - Round 1.

    - by James Michael Hare
    So I was reading Peter Kellner's blog entry on Resharper 5.0 and its LINQ refactoring and thought that was very cool.  But that raised a point I had always been curious about in my head -- which is a better choice: manual foreach loops or LINQ?    The answer is not really clear-cut.  There are two sides to any code cost arguments: performance and maintainability.  The first of these is obvious and quantifiable.  Given any two pieces of code that perform the same function, you can run them side-by-side and see which piece of code performs better.   Unfortunately, this is not always a good measure.  Well written assembly language outperforms well written C++ code, but you lose a lot in maintainability which creates a big techncial debt load that is hard to offset as the application ages.  In contrast, higher level constructs make the code more brief and easier to understand, hence reducing technical cost.   Now, obviously in this case we're not talking two separate languages, we're comparing doing something manually in the language versus using a higher-order set of IEnumerable extensions that are in the System.Linq library.   Well, before we discuss any further, let's look at some sample code and the numbers.  First, let's take a look at the for loop and the LINQ expression.  This is just a simple find comparison:       // find implemented via LINQ     public static bool FindViaLinq(IEnumerable<int> list, int target)     {         return list.Any(item => item == target);     }         // find implemented via standard iteration     public static bool FindViaIteration(IEnumerable<int> list, int target)     {         foreach (var i in list)         {             if (i == target)             {                 return true;             }         }           return false;     }   Okay, looking at this from a maintainability point of view, the Linq expression is definitely more concise (8 lines down to 1) and is very readable in intention.  You don't have to actually analyze the behavior of the loop to determine what it's doing.   So let's take a look at performance metrics from 100,000 iterations of these methods on a List<int> of varying sizes filled with random data.  For this test, we fill a target array with 100,000 random integers and then run the exact same pseudo-random targets through both searches.                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     Any         10       26          0.00046             30.00%     Iteration   10       20          0.00023             -     Any         100      116         0.00201             18.37%     Iteration   100      98          0.00118             -     Any         1000     1058        0.01853             16.78%     Iteration   1000     906         0.01155             -     Any         10,000   10,383      0.18189             17.41%     Iteration   10,000   8843        0.11362             -     Any         100,000  104,004     1.8297              18.27%     Iteration   100,000  87,941      1.13163             -   The LINQ expression is running about 17% slower for average size collections and worse for smaller collections.  Presumably, this is due to the overhead of the state machine used to track the iterators for the yield returns in the LINQ expressions, which seems about right in a tight loop such as this.   So what about other LINQ expressions?  After all, Any() is one of the more trivial ones.  I decided to try the TakeWhile() algorithm using a Count() to get the position stopped like the sample Pete was using in his blog that Resharper refactored for him into LINQ:       // Linq form     public static int GetTargetPosition1(IEnumerable<int> list, int target)     {         return list.TakeWhile(item => item != target).Count();     }       // traditionally iterative form     public static int GetTargetPosition2(IEnumerable<int> list, int target)     {         int count = 0;           foreach (var i in list)         {             if(i == target)             {                 break;             }               ++count;         }           return count;     }   Once again, the LINQ expression is much shorter, easier to read, and should be easier to maintain over time, reducing the cost of technical debt.  So I ran these through the same test data:                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile   10       41          0.00041             128%     Iteration   10       18          0.00018             -     TakeWhile   100      171         0.00171             88%     Iteration   100      91          0.00091             -     TakeWhile   1000     1604        0.01604             94%     Iteration   1000     825         0.00825             -     TakeWhile   10,000   15765       0.15765             92%     Iteration   10,000   8204        0.08204             -     TakeWhile   100,000  156950      1.5695              92%     Iteration   100,000  81635       0.81635             -     Wow!  I expected some overhead due to the state machines iterators produce, but 90% slower?  That seems a little heavy to me.  So then I thought, well, what if TakeWhile() is not the right tool for the job?  The problem is TakeWhile returns each item for processing using yield return, whereas our for-loop really doesn't care about the item beyond using it as a stop condition to evaluate. So what if that back and forth with the iterator state machine is the problem?  Well, we can quickly create an (albeit ugly) lambda that uses the Any() along with a count in a closure (if a LINQ guru knows a better way PLEASE let me know!), after all , this is more consistent with what we're trying to do, we're trying to find the first occurence of an item and halt once we find it, we just happen to be counting on the way.  This mostly matches Any().       // a new method that uses linq but evaluates the count in a closure.     public static int TakeWhileViaLinq2(IEnumerable<int> list, int target)     {         int count = 0;         list.Any(item =>             {                 if(item == target)                 {                     return true;                 }                   ++count;                 return false;             });         return count;     }     Now how does this one compare?                         List<T> On 100,000 Iterations     Method         Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile      10       41          0.00041             128%     Any w/Closure  10       23          0.00023             28%     Iteration      10       18          0.00018             -     TakeWhile      100      171         0.00171             88%     Any w/Closure  100      116         0.00116             27%     Iteration      100      91          0.00091             -     TakeWhile      1000     1604        0.01604             94%     Any w/Closure  1000     1101        0.01101             33%     Iteration      1000     825         0.00825             -     TakeWhile      10,000   15765       0.15765             92%     Any w/Closure  10,000   10802       0.10802             32%     Iteration      10,000   8204        0.08204             -     TakeWhile      100,000  156950      1.5695              92%     Any w/Closure  100,000  108378      1.08378             33%     Iteration      100,000  81635       0.81635             -     Much better!  It seems that the overhead of TakeAny() returning each item and updating the state in the state machine is drastically reduced by using Any() since Any() iterates forward until it finds the value we're looking for -- for the task we're attempting to do.   So the lesson there is, make sure when you use a LINQ expression you're choosing the best expression for the job, because if you're doing more work than you really need, you'll have a slower algorithm.  But this is true of any choice of algorithm or collection in general.     Even with the Any() with the count in the closure it is still about 30% slower, but let's consider that angle carefully.  For a list of 100,000 items, it was the difference between 1.01 ms and 0.82 ms roughly in a List<T>.  That's really not that bad at all in the grand scheme of things.  Even running at 90% slower with TakeWhile(), for the vast majority of my projects, an extra millisecond to save potential errors in the long term and improve maintainability is a small price to pay.  And if your typical list is 1000 items or less we're talking only microseconds worth of difference.   It's like they say: 90% of your performance bottlenecks are in 2% of your code, so over-optimizing almost never pays off.  So personally, I'll take the LINQ expression wherever I can because they will be easier to read and maintain (thus reducing technical debt) and I can rely on Microsoft's development to have coded and unit tested those algorithm fully for me instead of relying on a developer to code the loop logic correctly.   If something's 90% slower, yes, it's worth keeping in mind, but it's really not until you start get magnitudes-of-order slower (10x, 100x, 1000x) that alarm bells should really go off.  And if I ever do need that last millisecond of performance?  Well then I'll optimize JUST THAT problem spot.  To me it's worth it for the readability, speed-to-market, and maintainability.

    Read the article

  • Can connect to DNS addresses typed in the URL but not by IP addresses

    - by Ben
    I just changed over my modem to bridged mode, and changed my wireless router to PPPoE. My PC IP address is reserved and forwards port 80 to my computer's IP address based on my MAC address. I have a problem, however. I cannot access my local webserver by public IP address or my router 192.168.0.1 wirelessly from any other computer or iPad. I can, however, connect by this PC which is connected to the wireless router via ethernet. Via wireless, it says it cannot connect, however DNS addresses work (e.g. google.com, etc.) Any ideas?

    Read the article

  • OpenVPN, Server 12.04, connect to machines in home LAN behind VPN server

    - by inexion
    Problem: I've set up a working OpenVPN server, and am able to connect to it from anywhere using my mac laptop and tunnelblick. When I connect in, I'm assigned an IP address of 10.8.0.x, the server is 10.8.0.1, so I have no problems SSHing into it. Once SSHd in, I can even ping other machines (obviously) on my home network (192.168.1.x). Desired outcome: What I want, is, to connect to the VPN server, and instead of getting a 10.8.0.x address, I get a 192.168.1.x on my home network. I can't figure out how to talk to the OTHER machines on my home network WITHOUT being SSHd in to the VPN server. I'd like to just connect to my VPN server, then be a part of my home network. Attempted solutions: I've read that I need to set up routes, and/or enable IP forwarding. I enabled IP forwarding using sudo sysctl -w net.ipv4.ip_forward=1 and that doesn't seem to have done anything. I've also uncommented a line in the OpenVPN's server.conf file: # Push routes to the client to allow it # to reach other private subnets behind # the server. Remember that these # private subnets will also need # to know to route the OpenVPN client # address pool (10.8.0.0/255.255.255.0) # back to the OpenVPN server. push "route 192.168.1.0 255.255.255.0" ;push "route 192.168.20.0 255.255.255.0" But still no luck, I still get a 10.8.0.x address... I've also read I may have to add routes to the router itself, but haven't tried that. Any help appreciated, thanks!

    Read the article

  • Windows 7 Multi-NIC woes

    - by Eric
    I have Comcast business Internet here. It gives me 5 static IPs. Most of the machines in my house connect to a router like every other household. It has a 192.168.117.x subnet, DHCP Server, etc. and all is well. However, I have a second machine on MY desk that has a life Internet IP. Up until yesterday, this machine was running XP Pro. The primary NIC was manually set to 192.168.117.241 with no gateway, and the secondary NIC was manually set to 173.x.x.171 with a gateway of 173.x.x.174. This worked just fine for years. Yesterday I replaced that XP machine with a brand new Windows 7 x64 box. Again, I configured it the same way. The onboard NIC was given a static 192.168.117.x address with no gateway, and the secondary NIC was given a live Internet IP address with the proper router, etc. 2 Problems. First is that the internal network (192.168.117.x) is listed as a public network because there's no gateway, so that means no homegroup, no file sharing, none of that. And I can't change it from what I'm reading... The second is that the machine reports the "router" ip address as it's address, and not the address that it's supposed to. I'm ready to tear my hair out over this. Any ideas?

    Read the article

  • Why does void in C mean not void?

    - by Naftuli Tzvi Kay
    In strongly-typed languages like Java and C#, void (or Void) as a return type for a method seem to mean: This method doesn't return anything. Nothing. No return. You will not receive anything from this method. What's really strange is that in C, void as a return type or even as a method parameter type means: It could really be anything. You'd have to read the source code to find out. Good luck. If it's a pointer, you should really know what you're doing. Consider the following examples in C: void describe(void *thing) { Object *obj = thing; printf("%s.\n", obj->description); } void *move(void *location, Direction direction) { void *next = NULL; // logic! return next; } Obviously, the second method returns a pointer, which by definition could be anything. Since C is older than Java and C#, why did these languages adopt void as meaning "nothing" while C used it as "nothing or anything (when a pointer)"?

    Read the article

< Previous Page | 194 195 196 197 198 199 200 201 202 203 204 205  | Next Page >