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  • Forensic Analysis of the OOM-Killer

    - by Oddthinking
    Ubuntu's Out-Of-Memory Killer wreaked havoc on my server, quietly assassinating my applications, sendmail, apache and others. I've managed to learn what the OOM Killer is, and about its "badness" rules. While my machine is small, my applications are even smaller, and typically only half of my physical memory is in use, let alone swap-space, so I was surprised. I am trying to work out the culprit, but I don't know how to read the OOM-Killer logs. Can anyone please point me to a tutorial on how to read the data in the logs (what are ve, free and gen?), or help me parse these logs? Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 1, exc 2326 0 goal 2326 0... Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): task ebb0c6f0, thg d33a1b00, sig 1 Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 1, exc 2326 0 red 61795 745 Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 2, exc 122 0 goal 383 0... Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): task ebb0c6f0, thg d33a1b00, sig 1 Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 2, exc 383 0 red 61795 745 Apr 20 20:03:27 EL135 kernel: kill_signal(13516.0): task ebb0c6f0, thg d33a1b00, sig 2 Apr 20 20:03:27 EL135 kernel: OOM killed process watchdog (pid=14490, ve=13516) exited, free=43104 gen=24501. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=4457, ve=13516) exited, free=43104 gen=24502. Apr 20 20:03:27 EL135 kernel: OOM killed process ntpd (pid=10816, ve=13516) exited, free=43104 gen=24503. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=27401, ve=13516) exited, free=43104 gen=24504. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=29009, ve=13516) exited, free=43104 gen=24505. Apr 20 20:03:27 EL135 kernel: OOM killed process apache2 (pid=10557, ve=13516) exited, free=49552 gen=24506. Apr 20 20:03:27 EL135 kernel: OOM killed process apache2 (pid=24983, ve=13516) exited, free=53117 gen=24507. Apr 20 20:03:27 EL135 kernel: OOM killed process apache2 (pid=29129, ve=13516) exited, free=68493 gen=24508. Apr 20 20:03:27 EL135 kernel: OOM killed process sendmail-mta (pid=941, ve=13516) exited, free=68803 gen=24509. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=12418, ve=13516) exited, free=69330 gen=24510. Apr 20 20:03:27 EL135 kernel: OOM killed process python (pid=22953, ve=13516) exited, free=72275 gen=24511. Apr 20 20:03:27 EL135 kernel: OOM killed process apache2 (pid=6624, ve=13516) exited, free=76398 gen=24512. Apr 20 20:03:27 EL135 kernel: OOM killed process python (pid=23317, ve=13516) exited, free=94285 gen=24513. Apr 20 20:03:27 EL135 kernel: OOM killed process tail (pid=29030, ve=13516) exited, free=95339 gen=24514. Apr 20 20:03:28 EL135 kernel: OOM killed process apache2 (pid=20583, ve=13516) exited, free=101663 gen=24515. Apr 20 20:03:28 EL135 kernel: OOM killed process logger (pid=12894, ve=13516) exited, free=101694 gen=24516. Apr 20 20:03:28 EL135 kernel: OOM killed process bash (pid=21119, ve=13516) exited, free=101849 gen=24517. Apr 20 20:03:28 EL135 kernel: OOM killed process atd (pid=991, ve=13516) exited, free=101880 gen=24518. Apr 20 20:03:28 EL135 kernel: OOM killed process apache2 (pid=14649, ve=13516) exited, free=102748 gen=24519. Apr 20 20:03:28 EL135 kernel: OOM killed process grep (pid=21375, ve=13516) exited, free=132167 gen=24520. Apr 20 20:03:57 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 4, exc 4215 0 goal 4826 0... Apr 20 20:03:57 EL135 kernel: kill_signal(13516.0): task ede29370, thg df98b880, sig 1 Apr 20 20:03:57 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 4, exc 4826 0 red 189481 331 Apr 20 20:03:57 EL135 kernel: kill_signal(13516.0): task ede29370, thg df98b880, sig 2 Apr 20 20:04:53 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 5, exc 3564 0 goal 3564 0... Apr 20 20:04:53 EL135 kernel: kill_signal(13516.0): task c6c90110, thg cdb1a100, sig 1 Apr 20 20:04:53 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 5, exc 3564 0 red 189481 331 Apr 20 20:04:53 EL135 kernel: kill_signal(13516.0): task c6c90110, thg cdb1a100, sig 2 Apr 20 20:07:14 EL135 kernel: kill_signal(13516.0): selecting to kill, queued 0, seq 6, exc 8071 0 goal 8071 0... Apr 20 20:07:14 EL135 kernel: kill_signal(13516.0): task d7294050, thg c03f42c0, sig 1 Apr 20 20:07:14 EL135 kernel: kill_signal(13516.0): selected 1, signalled 1, queued 1, seq 6, exc 8071 0 red 189481 331 Apr 20 20:07:14 EL135 kernel: kill_signal(13516.0): task d7294050, thg c03f42c0, sig 2 Watchdog is a watchdog task, that was idle; nothing in the logs to suggest it had done anything for days. Its job is to restart one of the applications if it dies, so a bit ironic that it is the first to get killed. Tail was monitoring a few logs files. Unlikely to be consuming memory madly. The apache web-server only serves pages to a little old lady who only uses it to get to church on Sundays a couple of developers who were in bed asleep, and hadn't visited a page on the site for a few weeks. The only traffic it might have had is from the port-scanners; all the content is password-protected and not linked from anywhere, so no spiders are interested. Python is running two separate custom applications. Nothing in the logs to suggest they weren't humming along as normal. One of them was a relatively recent implementation, which makes suspect #1. It doesn't have any data-structures of any significance, and normally uses only about 8% of the total physical RAW. It hasn't misbehaved since. The grep is suspect #2, and the one I want to be guilty, because it was a once-off command. The command (which piped the output of a grep -r to another grep) had been started at least 30 minutes earlier, and the fact it was still running is suspicious. However, I wouldn't have thought grep would ever use a significant amount of memory. It took a while for the OOM killer to get to it, which suggests it wasn't going mad, but the OOM killer stopped once it was killed, suggesting it may have been a memory-hog that finally satisfied the OOM killer's blood-lust.

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  • IRQ problem with 2.6.32/2.6.39 kernel on Debian Squeeze x86_64

    - by MasterM
    I recently assembled a new computer so that all hardware is pretty new. Since then I've been experiencing some problem with IRQs when running Debian 6.0. On random occasions, usually after an hour or so of running I hear a beep and this shows up in dmesg: [ 3537.762795] irq 16: nobody cared (try booting with the "irqpoll" option) [ 3537.762797] Pid: 0, comm: swapper Tainted: P W O 2.6.39-2-amd64 #1 [ 3537.762798] Call Trace: [ 3537.762799] <IRQ> [<ffffffff810924d4>] ? __report_bad_irq+0x3a/0xa2 [ 3537.762803] [<ffffffff810926a4>] ? note_interrupt+0x168/0x1da [ 3537.762805] [<ffffffff81090dd4>] ? handle_irq_event_percpu+0x171/0x18f [ 3537.762807] [<ffffffff8100e0e2>] ? read_tsc+0x5/0x16 [ 3537.762809] [<ffffffff8106b8a2>] ? update_ts_time_stats+0x32/0x6b [ 3537.762810] [<ffffffff81090e26>] ? handle_irq_event+0x34/0x52 [ 3537.762812] [<ffffffff81063fb7>] ? sched_clock_idle_wakeup_event+0x12/0x1c [ 3537.762813] [<ffffffff81092df2>] ? handle_fasteoi_irq+0x82/0xa4 [ 3537.762815] [<ffffffff8100aadb>] ? handle_irq+0x1a/0x23 [ 3537.762816] [<ffffffff8100a384>] ? do_IRQ+0x45/0xaa [ 3537.762818] [<ffffffff81332c93>] ? common_interrupt+0x13/0x13 [ 3537.762818] <EOI> [<ffffffff81332c8e>] ? common_interrupt+0xe/0x13 [ 3537.762821] [<ffffffff81026800>] ? native_safe_halt+0x2/0x3 [ 3537.762829] [<ffffffffa016ed58>] ? acpi_idle_do_entry+0x39/0x62 [processor] [ 3537.762831] [<ffffffffa016edde>] ? acpi_idle_enter_c1+0x5d/0xad [processor] [ 3537.762834] [<ffffffff81261033>] ? cpuidle_idle_call+0x11f/0x1cc [ 3537.762835] [<ffffffff81008dd2>] ? cpu_idle+0xab/0xe1 [ 3537.762837] [<ffffffff8169fc60>] ? start_kernel+0x3e0/0x3eb [ 3537.762838] [<ffffffff8169f3c8>] ? x86_64_start_kernel+0x102/0x10f [ 3537.762839] handlers: [ 3537.762840] [<ffffffffa0358d5a>] (rtl8169_interrupt+0x0/0x2d7 [r8169]) [ 3537.762842] [<ffffffffa08ff2ca>] (nv_kern_isr+0x0/0x54 [nvidia]) [ 3537.762902] Disabling IRQ #16 After that Xorg either hogs on CPU or is unstable (up to hanging the system completely). When I restart Xorg everything is fine again and the problem doesn't occur until next reboot. I tried to upgrade the kernel from stock 2.6.32 to 2.6.39 from unstable repository but that didn't help. Booting with irqpoll option only seems to prolong the initial time period after which the problem occurs. I'm using latest NVIDIA drivers and Realtek firmware from firmware-realtek package. I have two GTX 560Ti that run in SLI. Disabling SLI or taking out one card completely doesn't solve the problem either. Output of uname -a is: Linux whitestar 2.6.39-2-amd64 #1 SMP Wed Jun 8 11:01:04 UTC 2011 x86_64 GNU/Linux Output of lspci is: 00:00.0 Host bridge: Intel Corporation Sandy Bridge DRAM Controller (rev 09) 00:01.0 PCI bridge: Intel Corporation Sandy Bridge PCI Express Root Port (rev 09) 00:01.1 PCI bridge: Intel Corporation Sandy Bridge PCI Express Root Port (rev 09) 00:16.0 Communication controller: Intel Corporation Cougar Point HECI Controller #1 (rev 04) 00:19.0 Ethernet controller: Intel Corporation 82579V Gigabit Network Connection (rev 05) 00:1a.0 USB Controller: Intel Corporation Cougar Point USB Enhanced Host Controller #2 (rev 05) 00:1b.0 Audio device: Intel Corporation Cougar Point High Definition Audio Controller (rev 05) 00:1c.0 PCI bridge: Intel Corporation Cougar Point PCI Express Root Port 1 (rev b5) 00:1c.1 PCI bridge: Intel Corporation Cougar Point PCI Express Root Port 2 (rev b5) 00:1c.2 PCI bridge: Intel Corporation Cougar Point PCI Express Root Port 3 (rev b5) 00:1c.4 PCI bridge: Intel Corporation Cougar Point PCI Express Root Port 5 (rev b5) 00:1c.6 PCI bridge: Intel Corporation 82801 PCI Bridge (rev b5) 00:1d.0 USB Controller: Intel Corporation Cougar Point USB Enhanced Host Controller #1 (rev 05) 00:1f.0 ISA bridge: Intel Corporation Cougar Point LPC Controller (rev 05) 00:1f.2 SATA controller: Intel Corporation Cougar Point 6 port SATA AHCI Controller (rev 05) 00:1f.3 SMBus: Intel Corporation Cougar Point SMBus Controller (rev 05) 01:00.0 VGA compatible controller: nVidia Corporation Device 1200 (rev a1) 01:00.1 Audio device: nVidia Corporation Device 0e0c (rev a1) 02:00.0 VGA compatible controller: nVidia Corporation Device 1200 (rev a1) 02:00.1 Audio device: nVidia Corporation Device 0e0c (rev a1) 04:00.0 USB Controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 04) 06:00.0 USB Controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 04) 07:00.0 PCI bridge: Device 1b21:1080 (rev 01) 08:02.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8110SC/8169SC Gigabit Ethernet (rev 10) 08:03.0 FireWire (IEEE 1394): VIA Technologies, Inc. VT6306/7/8 [Fire II(M)] IEEE 1394 OHCI Controller (rev c0) Contents of /proc/interrupts: CPU0 CPU1 CPU2 CPU3 CPU4 CPU5 CPU6 CPU7 0: 77 0 0 0 0 0 0 0 IO-APIC-edge timer 1: 2 0 0 0 0 0 0 0 IO-APIC-edge i8042 8: 1 0 0 0 0 0 0 0 IO-APIC-edge rtc0 9: 0 0 0 0 0 0 0 0 IO-APIC-fasteoi acpi 12: 4 0 0 0 0 0 0 0 IO-APIC-edge i8042 16: 699083 0 0 0 0 0 0 0 IO-APIC-fasteoi nvidia, eth0 17: 87810 0 0 0 0 0 0 0 IO-APIC-fasteoi firewire_ohci, hda_intel, nvidia 18: 242 0 0 0 0 0 0 0 IO-APIC-fasteoi hda_intel 23: 85925 0 0 0 0 0 0 0 IO-APIC-fasteoi ehci_hcd:usb5, ehci_hcd:usb6 40: 0 0 0 0 0 0 0 0 PCI-MSI-edge PCIe PME 41: 0 0 0 0 0 0 0 0 PCI-MSI-edge PCIe PME 42: 0 0 0 0 0 0 0 0 PCI-MSI-edge PCIe PME 43: 0 0 0 0 0 0 0 0 PCI-MSI-edge PCIe PME 44: 0 0 0 0 0 0 0 0 PCI-MSI-edge PCIe PME 45: 0 0 0 0 0 0 0 0 PCI-MSI-edge PCIe PME 46: 79853 0 0 0 0 0 0 0 PCI-MSI-edge ahci 48: 1 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 49: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 50: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 51: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 52: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 53: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 54: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 55: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 56: 1 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 57: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 58: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 59: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 60: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 61: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 62: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 63: 0 0 0 0 0 0 0 0 PCI-MSI-edge xhci_hcd 64: 173506 0 0 0 0 0 0 0 PCI-MSI-edge hda_intel NMI: 482 89 25 13 277 24 11 10 Non-maskable interrupts LOC: 783857 194752 114133 70577 372438 179065 117179 162016 Local timer interrupts SPU: 0 0 0 0 0 0 0 0 Spurious interrupts PMI: 482 89 25 13 277 24 11 10 Performance monitoring interrupts IWI: 0 0 0 0 0 0 0 0 IRQ work interrupts RES: 131917 46750 7432 3291 150003 9576 3435 3067 Rescheduling interrupts CAL: 2759 6563 7150 6997 5387 7140 7269 6678 Function call interrupts TLB: 4396 2038 1336 492 5434 1896 1121 606 TLB shootdowns TRM: 0 0 0 0 0 0 0 0 Thermal event interrupts THR: 0 0 0 0 0 0 0 0 Threshold APIC interrupts MCE: 0 0 0 0 0 0 0 0 Machine check exceptions MCP: 37 37 37 37 37 37 37 37 Machine check polls ERR: 0 MIS: 0 Last but not least, right after boot-up those lines are usually present in dmesg: [ 18.367094] hda-intel: IRQ timing workaround is activated for card #1. Suggest a bigger bdl_pos_adj. [ 18.458859] hda-intel: IRQ timing workaround is activated for card #2. Suggest a bigger bdl_pos_adj. I'm not sure if it's related or a symptom of a bigger problem so I'm posting it just in case. I don't really know what other information might be of relevance here. Don't hesitate to ask for more in the comments.

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  • Is this slow WPF TextBlock performance expected?

    - by Ben Schoepke
    Hi, I am doing some benchmarking to determine if I can use WPF for a new product. However, early performance results are disappointing. I made a quick app that uses data binding to display a bunch of random text inside of a list box every 100 ms and it was eating up ~15% CPU. So I made another quick app that skipped the data binding/data template scheme and does nothing but update 10 TextBlocks that are inside of a ListBox every 100 ms (the actual product wouldn't require 100 ms updates, more like 500 ms max, but this is a stress test). I'm still seeing ~10-15% CPU usage. Why is this so high? Is it because of all the garbage strings? Here's the XAML: <Grid> <ListBox x:Name="numericsListBox"> <ListBox.Resources> <Style TargetType="TextBlock"> <Setter Property="FontSize" Value="48"/> <Setter Property="Width" Value="300"/> </Style> </ListBox.Resources> <TextBlock/> <TextBlock/> <TextBlock/> <TextBlock/> <TextBlock/> <TextBlock/> <TextBlock/> <TextBlock/> <TextBlock/> <TextBlock/> </ListBox> </Grid> Here's the code behind: public partial class Window1 : Window { private int _count = 0; public Window1() { InitializeComponent(); } private void OnLoad(object sender, RoutedEventArgs e) { var t = new DispatcherTimer(TimeSpan.FromSeconds(0.1), DispatcherPriority.Normal, UpdateNumerics, Dispatcher); t.Start(); } private void UpdateNumerics(object sender, EventArgs e) { ++_count; foreach (object textBlock in numericsListBox.Items) { var t = textBlock as TextBlock; if (t != null) t.Text = _count.ToString(); } } } Any ideas for a better way to quickly render text? My computer: XP SP3, 2.26 GHz Core 2 Duo, 4 GB RAM, Intel 4500 HD integrated graphics. And that is an order of magnitude beefier than the hardware I'd need to develop for in the real product.

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  • Speed Problem with Wireless Connectivity on Cisco 877w

    - by Carl Crawley
    Having a bit of a weird one with my local LAN setup. I recently installed a Cisco 877W router on my DSL2+ connection and all is working really well.. Upgraded the IOS to 12.4 and my wired clients are streaming connectivity superfast at 1.3mb/s. However, there seems to be an issue with my wireless clients - I can't seem to stream any data across the local wireless connection (LAN) and using the Internet, whilst responsive enough isn't really comparable with the wired connection speed. For example, all devices are connected to an 8 Port Gb switch on FE0 from the Router with a NAS disk and on my wired clients, I can transfer/stream etc absolutely fine - however, transferring a local 700Mb file on my local LAN estimates 7-8 hours to transfer :( The Wireless config is as follows : interface Dot11Radio0 description WIRELESS INTERFACE no ip address ! encryption mode ciphers tkip ! ssid [MySSID] ! speed basic-1.0 basic-2.0 basic-5.5 6.0 9.0 basic-11.0 channel 2462 station-role root rts threshold 2312 world-mode dot11d country GB indoor bridge-group 1 bridge-group 1 subscriber-loop-control bridge-group 1 spanning-disabled bridge-group 1 block-unknown-source no bridge-group 1 source-learning no bridge-group 1 unicast-flooding All devices are connected to the Gb Switch which is connected to FE0 with the following: Hardware is Fast Ethernet, address is 0021.a03e.6519 (bia 0021.a03e.6519) Description: Uplink to Switch MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full-duplex, 100Mb/s ARP type: ARPA, ARP Timeout 04:00:00 Last input never, output never, output hang never Last clearing of "show interface" counters never Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: fifo Output queue: 0/40 (size/max) 5 minute input rate 14000 bits/sec, 19 packets/sec 5 minute output rate 167000 bits/sec, 23 packets/sec 177365 packets input, 52089562 bytes, 0 no buffer Received 919 broadcasts, 0 runts, 0 giants, 0 throttles 260 input errors, 260 CRC, 0 frame, 0 overrun, 0 ignored 0 input packets with dribble condition detected 156673 packets output, 106218222 bytes, 0 underruns 0 output errors, 0 collisions, 2 interface resets 0 babbles, 0 late collision, 0 deferred 0 lost carrier, 0 no carrier 0 output buffer failures, 0 output buffers swapped out Not sure why I'm having problems on the wireless and I've reached the end of my Cisco knowledge... Thanks for any pointers! Carl

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  • Is there an equivalent to Java's ClassFileTransformer in .NET? (a way to replace a class)

    - by Alix
    I've been searching for this for quite a while with no luck so far. Is there an equivalent to Java's ClassFileTransformer in .NET? Basically, I want to create a class CustomClassFileTransformer (which in Java would implement the interface ClassFileTransformer) that gets called whenever a class is loaded, and is allowed to tweak it and replace it with the tweaked version. I know there are frameworks that do similar things, but I was looking for something more straightforward, like implementing my own ClassFileTransformer. Is it possible? EDIT #1. More details about why I need this: Basically, I have a C# application and I need to monitor the instructions it wants to run in order to detect read or write operations to fields (operations Ldfld and Stfld) and insert some instructions before the read/write takes place. I know how to do this (except for the part where I need to be invoked to replace the class): for every method whose code I want to monitor, I must: Get the method's MethodBody using MethodBase.GetMethodBody() Transform it to byte array with MethodBody.GetILAsByteArray(). The byte[] it returns contains the bytecode. Analyse the bytecode as explained here, possibly inserting new instructions or deleting/modifying existing ones by changing the contents of the array. Create a new method and use the new bytecode to create its body, with MethodBuilder.CreateMethodBody(byte[] il, int count), where il is the array with the bytecode. I put all these tweaked methods in a new class and use the new class to replace the one that was originally going to be loaded. An alternative to replacing classes would be somehow getting notified whenever a method is invoked. Then I'd replace the call to that method with a call to my own tweaked method, which I would tweak only the first time is invoked and then I'd put it in a dictionary for future uses, to reduce overhead (for future calls I'll just look up the method and invoke it; I won't need to analyse the bytecode again). I'm currently investigating ways to do this and LinFu looks pretty interesting, but if there was something like a ClassFileTransformer it would be much simpler: I just rewrite the class, replace it, and let the code run without monitoring anything. An additional note: the classes may be sealed. I want to be able to replace any kind of class, I cannot impose restrictions on their attributes. EDIT #2. Why I need to do this at runtime. I need to monitor everything that is going on so that I can detect every access to data. This applies to the code of library classes as well. However, I cannot know in advance which classes are going to be used, and even if I knew every possible class that may get loaded it would be a huge performance hit to tweak all of them instead of waiting to see whether they actually get invoked or not. POSSIBLE (BUT PRETTY HARDCORE) SOLUTION. In case anyone is interested (and I see the question has been faved, so I guess someone is), this is what I'm looking at right now. Basically I'd have to implement the profiling API and I'll register for the events that I'm interested in, in my case whenever a JIT compilation starts. An extract of the blogpost: In your ICorProfilerCallback2::ModuleLoadFinished callback, you call ICorProfilerInfo2::GetModuleMetadata to get a pointer to a metadata interface on that module. QI for the metadata interface you want. Search MSDN for "IMetaDataImport", and grope through the table of contents to find topics on the metadata interfaces. Once you're in metadata-land, you have access to all the types in the module, including their fields and function prototypes. You may need to parse metadata signatures and this signature parser may be of use to you. In your ICorProfilerCallback2::JITCompilationStarted callback, you may use ICorProfilerInfo2::GetILFunctionBody to inspect the original IL, and ICorProfilerInfo2::GetILFunctionBodyAllocator and then ICorProfilerInfo2::SetILFunctionBody to replace that IL with your own. The great news: I get notified when a JIT compilation starts and I can replace the bytecode right there, without having to worry about replacing the class, etc. The not-so-great news: you cannot invoke managed code from the API's callback methods, which makes sense but means I'm on my own parsing the IL code, etc, as opposed to be able to use Cecil, which would've been a breeze. I don't think there's a simpler way to do this without using AOP frameworks (such as PostSharp). If anyone has any other idea please let me know. I'm not marking the question as answered yet.

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  • What to filter when providing very limited open WiFi to a small conference or meeting?

    - by Tim Farley
    Executive Summary The basic question is: if you have a very limited bandwidth WiFi to provide Internet for a small meeting of only a day or two, how do you set the filters on the router to avoid one or two users monopolizing all the available bandwidth? For folks who don't have the time to read the details below, I am NOT looking for any of these answers: Secure the router and only let a few trusted people use it Tell everyone to turn off unused services & generally police themselves Monitor the traffic with a sniffer and add filters as needed I am aware of all of that. None are appropriate for reasons that will become clear. ALSO NOTE: There is already a question concerning providing adequate WiFi at large (500 attendees) conferences here. This question concerns SMALL meetings of less than 200 people, typically with less than half that using the WiFi. Something that can be handled with a single home or small office router. Background I've used a 3G/4G router device to provide WiFi to small meetings in the past with some success. By small I mean single-room conferences or meetings on the order of a barcamp or Skepticamp or user group meeting. These meetings sometimes have technical attendees there, but not exclusively. Usually less than half to a third of the attendees will actually use the WiFi. Maximum meeting size I'm talking about is 100 to 200 people. I typically use a Cradlepoint MBR-1000 but many other devices exist, especially all-in-one units supplied by 3G and/or 4G vendors like Verizon, Sprint and Clear. These devices take a 3G or 4G internet connection and fan it out to multiple users using WiFi. One key aspect of providing net access this way is the limited bandwidth available over 3G/4G. Even with something like the Cradlepoint which can load-balance multiple radios, you are only going to achieve a few megabits of download speed and maybe a megabit or so of upload speed. That's a best case scenario. Often it is considerably slower. The goal in most of these meeting situations is to allow folks access to services like email, web, social media, chat services and so on. This is so they can live-blog or live-tweet the proceedings, or simply chat online or otherwise stay in touch (with both attendees and non-attendees) while the meeting proceeds. I would like to limit the services provided by the router to just those services that meet those needs. Problems In particular I have noticed a couple of scenarios where particular users end up abusing most of the bandwidth on the router, to the detriment of everyone. These boil into two areas: Intentional use. Folks looking at YouTube videos, downloading podcasts to their iPod, and otherwise using the bandwidth for things that really aren't appropriate in a meeting room where you should be paying attention to the speaker and/or interacting.At one meeting that we were live-streaming (over a separate, dedicated connection) via UStream, I noticed several folks in the room that had the UStream page up so they could interact with the meeting chat - apparently oblivious that they were wasting bandwidth streaming back video of something that was taking place right in front of them. Unintentional use. There are a variety of software utilities that will make extensive use of bandwidth in the background, that folks often have installed on their laptops and smartphones, perhaps without realizing.Examples: Peer to peer downloading programs such as Bittorrent that run in the background Automatic software update services. These are legion, as every major software vendor has their own, so one can easily have Microsoft, Apple, Mozilla, Adobe, Google and others all trying to download updates in the background. Security software that downloads new signatures such as anti-virus, anti-malware, etc. Backup software and other software that "syncs" in the background to cloud services. For some numbers on how much network bandwidth gets sucked up by these non-web, non-email type services, check out this recent Wired article. Apparently web, email and chat all together are less than one quarter of the Internet traffic now. If the numbers in that article are correct, by filtering out all the other stuff I should be able to increase the usefulness of the WiFi four-fold. Now, in some situations I've been able to control access using security on the router to limit it to a very small group of people (typically the organizers of the meeting). But that's not always appropriate. At an upcoming meeting I would like to run the WiFi without security and let anyone use it, because it happens at the meeting location the 4G coverage in my town is particularly excellent. In a recent test I got 10 Megabits down at the meeting site. The "tell people to police themselves" solution mentioned at top is not appropriate because of (a) a largely non-technical audience and (b) the unintentional nature of much of the usage as described above. The "run a sniffer and filter as needed" solution is not useful because these meetings typically only last a couple of days, often only one day, and have a very small volunteer staff. I don't have a person to dedicate to network monitoring, and by the time we got the rules tweaked completely the meeting will be over. What I've Got First thing, I figured I would use OpenDNS's domain filtering rules to filter out whole classes of sites. A number of video and peer-to-peer sites can be wiped out using this. (Yes, I am aware that filtering via DNS technically leaves the services accessible - remember, these are largely non-technical users attending a 2 day meeting. It's enough). I figured I would start with these selections in OpenDNS's UI: I figure I will probably also block DNS (port 53) to anything other than the router itself, so that folks can't bypass my DNS configuration. A savvy user could get around this, because I'm not going to put a lot of elaborate filters on the firewall, but I don't care too much. Because these meetings don't last very long, its probably not going to be worth the trouble. This should cover the bulk of the non-web traffic, i.e. peer-to-peer and video if that Wired article is correct. Please advise if you think there are severe limitations to the OpenDNS approach. What I Need Note that OpenDNS focuses on things that are "objectionable" in some context or another. Video, music, radio and peer-to-peer all get covered. I still need to cover a number of perfectly reasonable things that we just want to block because they aren't needed in a meeting. Most of these are utilities that upload or download legit things in the background. Specifically, I'd like to know port numbers or DNS names to filter in order to effectively disable the following services: Microsoft automatic updates Apple automatic updates Adobe automatic updates Google automatic updates Other major software update services Major virus/malware/security signature updates Major background backup services Other services that run in the background and can eat lots of bandwidth I also would like any other suggestions you might have that would be applicable. Sorry to be so verbose, but I find it helps to be very, very clear on questions of this nature, and I already have half a solution with the OpenDNS thing.

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  • Boggling Direct3D9 dynamic vertex buffer Lock crash/post-lock failure on Intel GMA X3100.

    - by nj
    Hi, For starters I'm a fairly seasoned graphics programmer but as wel all know, everyone makes mistakes. Unfortunately the codebase is a bit too large to start throwing sensible snippets here and re-creating the whole situation in an isolated CPP/codebase is too tall an order -- for which I am sorry, do not have the time. I'll do my best to explain. B.t.w, I will of course supply specific pieces of code if someone wonders how I'm handling this-or-that! As with all resources in the D3DPOOL_DEFAULT pool, when the device context is taken away from you you'll sooner or later will have to reset your resources. I've built a mechanism to handle this for all relevant resources that's been working for years; but that fact nothingwithstanding I've of course checked, asserted and doubted any assumption since this bug came to light. What happens is as follows: I have a rather large dynamic vertex buffer, exact size 18874368 bytes. This buffer is locked (and discarded fully using the D3DLOCK_DISCARD flag) each frame prior to generating dynamic geometry (isosurface-related, f.y.i) to it. This works fine, until, of course, I start to reset. It might take 1 time, it might take 2 or it might take 5 resets to set off a bug that causes an access violation either on the pointer returned by the Lock() operation on the renewed resource or a plain crash -- regarding a somewhat similar address, but without the offset that it has tacked on to it in the first case because in that case we're somewhere halfway writing -- iside the D3D9 dll Lock() call. I've tested this on other hardware, upgraded my GMA X3100 drivers (using a MacBook with BootCamp) to the latest ones, but I can't reproduce it on any other machine and I'm at a loss about what's wrong here. I have tried to reproduce a similar situation with a similar buffer (I've got a large scratch pad of the same type I filled with quads) and beyond a certain amount of bytes it started to behave likewise. I'm not asking for a solution here but I'm very interested if there are other developers here who have battled with the same foe or maybe some who can point me in some insightful direction, maybe ask some questions that might shed a light on what I may or may not be overlooking. Another interesting artifact is that the vertex buffer starts to bug if I supply both D3DLOCK_DISCARD and D3DLOCK_NOOVERWRITE together which, even though not very logical (you're not going to overwrite if you've just discarded all), gives graphics glitches. Thanks and any corrections are more than welcome. Niels p.s - A friend of mine raised the valid point that it is a huge buffer for onboard video RAM and it's being at least double or triple buffered internally due to it's dynamic nature. On the other hand, the debug output (D3D9 debug DLL + max. warning output) remains silent. p.s 2 - Had it tested on more machines and still works -- it's probably a matter of circumstance: the huge dynamic, internally double/trippled buffered buffer, not a lot of memory and drivers that don't complain when they should.. Unless someone has a better suggestion; I'd still love to hear it :)

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  • not getting voice , which is recorded could you suggest me what is the bug in the below code ?

    - by kumaryr
    AVAudioSession *audioSession = [AVAudioSession sharedInstance]; NSError *err = nil; [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:&err]; if(err){ NSLog(@"audioSession: %@ %d %@", [err domain], [err code], [[err userInfo] description]); return; } [audioSession setActive:YES error:&err]; err = nil; if(err){ NSLog(@"audioSession: %@ %d %@", [err domain], [err code], [[err userInfo] description]); return; } NSMutableDictionary *recordSetting = [[NSMutableDictionary alloc] init]; [recordSetting setValue :[NSNumber numberWithInt: kAudioFormatAppleIMA4] forKey:AVFormatIDKey]; [recordSetting setValue:[NSNumber numberWithFloat:40000.0] forKey:AVSampleRateKey]; [recordSetting setValue:[NSNumber numberWithInt: 2] forKey:AVNumberOfChannelsKey]; [recordSetting setValue :[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey]; [recordSetting setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey]; [recordSetting setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey]; // Create a new dated file NSDate *now = [NSDate dateWithTimeIntervalSinceNow:0]; NSString *caldate = [now description]; NSString *recorderFilePath = [[NSString stringWithFormat:@"%@/%@.caf", DOCUMENTS_FOLDER, caldate] retain]; NSLog(recorderFilePath); url = [NSURL fileURLWithPath:recorderFilePath]; err = nil; recorder = [[ AVAudioRecorder alloc] initWithURL:url settings:recordSetting error:&err]; if(!recorder){ NSLog(@"recorder: %@ %d %@", [err domain], [err code], [[err userInfo] description]); UIAlertView *alert = [[UIAlertView alloc] initWithTitle: @"Warning" message: [err localizedDescription] delegate: nil cancelButtonTitle:@"OK" otherButtonTitles:nil]; [alert show]; [alert release]; return; } //prepare to record [recorder setDelegate:self]; [recorder prepareToRecord]; recorder.meteringEnabled = YES; BOOL audioHWAvailable = audioSession.inputIsAvailable; if (! audioHWAvailable) { UIAlertView *cantRecordAlert = [[UIAlertView alloc] initWithTitle: @"Warning" message: @"Audio input hardware not available" delegate: nil cancelButtonTitle:@"OK" otherButtonTitles:nil]; [cantRecordAlert show]; [cantRecordAlert release]; return; } //[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector( updateTimerDisplay) userInfo:nil repeats:YES]; [recorder recordForDuration:(NSTimeInterval)10 ]; // [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector( updateTimerDisplay) userInfo:nil repeats:YES];

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  • Why is cell phone software still so primitive?

    - by Tomislav Nakic-Alfirevic
    I don't do mobile development, but it strikes me as odd that features like this aren't available by default on most phones: full text search: searches all address book contents, messages, anything else being a plus better call management: e.g. a rotating audio call log, meaning you always have the last N calls recorded for your listening pleasure later (your little girl just said her first "da-da" while you were on a business trip, you had a telephone job interview, you received complex instructions to do something etc.) bluetooth remote control (like e.g. anyRemote, but available by default on a bluetooth phone) no multitasking capabilities worth mentioning and in general no e.g. weekly software updates, making the phone much more usable (even if it had to be done over USB, rather than over the network). I'm sure I was dumbfounded by the lack or design of other features as well, but they don't come to mind right now. To clarify, I'm not talking about smartphones here: my plain, 2-year old phone has a CPU an order of magnitude faster than my first PC, about as much storage space and it's ridiculous how bad (slow, unwieldy) the software is and it's not one phone or one manufacturer. What keeps the (to me) obvious software functionality vacuum on a capable hardware platform from being filled up? Edit: I believe a clarification on the multitasking point might be beneficial. I'll use my phone as an example, although the point is much more general. The phone can multitask and in fact does: you can listen to music and do something else at the same time. On the other hand, the way the software has been designed makes multitasking next to useless. (Ditto with the external touch screen: it can take touch commands, but only one application makes use of it, and only with 3 commands.) To take the multitasking example to the extreme, if I plug my phone into my laptop and it registers as an external disk, it doesn't allow any kind of operation: messages, calling, calendar, everything out of reach, although I can receive a call. No "battery life" issue there: it's charging while connected. BTW, another example of design below the current state of the art: I don't see a phone on the horizon which will remember where in an audio or video file you were when you stopped listening/watching it last time (podcasts are a good use case). Simplistic rewind/fast forward functionality only aggravates the problem.

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  • No exception, no error, still i dont recieve the json object from my http post

    - by user2978538
    My source code: final Thread t = new Thread() { public void run() { Looper.prepare(); HttpClient client = new DefaultHttpClient(); HttpConnectionParams.setConnectionTimeout(client.getParams(), 10000); HttpResponse response; JSONObject obj = new JSONObject(); try { HttpPost post = new HttpPost("http://pc.dyndns-office.com/mobile.asp"); obj.put("Model", ReadIn1); obj.put("Product", ReadIn2); obj.put("Manufacturer", ReadIn3); obj.put("RELEASE", ReadIn4); obj.put("SERIAL", ReadIn5); obj.put("ID", ReadIn6); obj.put("ANDROID_ID", ReadIn7); obj.put("Language", ReadIn8); obj.put("BOARD", ReadIn9); obj.put("BOOTLOADER", ReadIn10); obj.put("BRAND", ReadIn11); obj.put("CPU_API", ReadIn12); obj.put("DISPLAY", ReadIn13); obj.put("FINGERPRINT", ReadIn14); obj.put("HARDWARE", ReadIn15); obj.put("UUID", ReadIn16); StringEntity se = new StringEntity(obj.toString()); se.setContentType(new BasicHeader(HTTP.CONTENT_TYPE, "application/json")); post.setEntity(se); post.setHeader("host", "http://pc.dyndns-office.com/mobile.asp"); response = client.execute(post); if (response != null) { InputStream in = response.getEntity().getContent(); } } catch (Exception e) { e.printStackTrace(); } Looper.loop(); } }; t.start(); } } i want to send an Json object to a Website. As far as I can see, I set the header, but still I get this exception, can someone help me? (I'm using Android-Studio) __ Edit: i don't get any exceptions anymore, but still i do not receive the json packet. When i manually call the website i get a log file entry. Does anyone know, what's wrong? Edit2: When i debug i get as response "HTTP/1.1 400 bad request" i'm sure its not an permission problem. Any ideas?

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  • Reverse proxy for a REST web service using ADFS/AD and WebApi

    - by Kai Friis
    I need to implement a reverse proxy for a REST webservice behind a firewall. The reverse proxy should authenticate against an enterprise ADFS 2.0 server, preferably using claims in .net 4.5. The clients will be a mix of iOS, Android and web. I’m completely new to this topic; I’ve tried to implement the service as a REST service using WebApi, WIF and the new Identity and Access control in VS 2012, with no luck. I have also tried to look into Brock Allen’s Thinktecture.IdentityModel.45, however then my head was spinning so I didn’t see the difference between it and Windows Identity Foundation with the Identity and Access control. So I think I need to step back and get some advice on how to do this. There are several ways to this, as far as I understand it. In hardware. Set up our Citrix Netscaler as a reverse proxy. I have no idea how to do that, however if it’s a good solution I can always hire someone who knows… Do it in the webserver, like IIS. I haven’t tried it; do not know if it will work. Create a web service to do it. 3.1 Implement it as a SOAP service using WCF. As I understand it ADFS do not support REST so I have to use SOAP. The problem is mobile device do not like SOAP, neither do I… However if it’s the best way, I have to do it. 3.2 Use Azure Access Control Service. It might work, however the timing is not good. Our enterprise is considering several cloud options, and us jumping on the azure wagon on our own might not be the smartest thing to do right now. However if it is the only options, we can do it. I just prefer not to use it right now. Right now I feel there are too many options, and I do not know which one will work. If someone can point me in the right directions, which path to pursue, I would be very grateful.

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  • NfcAdapter.getDefaultAdapter(this) returns null in emulator

    - by DixieFlatline
    I am trying to test ForegroundDispatch (http://developer.android.com/resources/samples/ApiDemos/src/com/example/android/apis/nfc/ForegroundDispatch.html) in emulator API 10 (Android 2.3.3). When i call NfcAdapter.getDefaultAdapter(this), i get null. Why is this so? Code: public class ForegroundDispatch extends Activity { private NfcAdapter mAdapter; private PendingIntent mPendingIntent; private IntentFilter[] mFilters; private String[][] mTechLists; private TextView mText; private int mCount = 0; @Override public void onCreate(Bundle savedState) { super.onCreate(savedState); setContentView(R.layout.foreground_dispatch); mText = (TextView) findViewById(R.id.text); mText.setText("Scan a tag"); mAdapter = NfcAdapter.getDefaultAdapter(this); // Create a generic PendingIntent that will be deliver to this activity. The NFC stack // will fill in the intent with the details of the discovered tag before delivering to // this activity. mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0); // Setup an intent filter for all MIME based dispatches IntentFilter ndef = new IntentFilter(NfcAdapter.ACTION_NDEF_DISCOVERED); try { ndef.addDataType("*/*"); } catch (MalformedMimeTypeException e) { throw new RuntimeException("fail", e); } mFilters = new IntentFilter[] { ndef, }; // Setup a tech list for all NfcF tags mTechLists = new String[][] { new String[] { NfcF.class.getName() } }; } @Override public void onResume() { super.onResume(); mAdapter.enableForegroundDispatch(this, mPendingIntent, mFilters, mTechLists); //CRASHES HERE BECAUSE mAdapter IS NULL } @Override public void onNewIntent(Intent intent) { Log.i("Foreground dispatch", "Discovered tag with intent: " + intent); mText.setText("Discovered tag " + ++mCount + " with intent: " + intent); } @Override public void onPause() { super.onPause(); mAdapter.disableForegroundDispatch(this); } } My manifest: <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.neka.znacka" android:versionCode="1" android:versionName="1.0"> <uses-sdk android:minSdkVersion="10" /> <uses-permission android:name="android.permission.NFC"></uses-permission> <uses-feature android:name="android.hardware.nfc" android:required="true" /> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".Uvodna" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name="Simulator"> </activity> </application> Any ideas?

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  • Will creating a background thread in a WCF service during a call, take up a thread in the ASP .NET t

    - by Nate Pinchot
    The following code is part of a WCF service. Will eventWatcher take up a thread in the ASP .NET thread pool, even if it is set IsBackground = true? /// <summary> /// Provides methods to work with the PhoneSystem web services SDK. /// This is a singleton since we need to keep track of what lines (extensions) are open. /// </summary> public sealed class PhoneSystemWebServiceFactory : IDisposable { // singleton instance reference private static readonly PhoneSystemWebServiceFactory instance = new PhoneSystemWebServiceFactory(); private static readonly object l = new object(); private static volatile Hashtable monitoredExtensions = new Hashtable(); private static readonly PhoneSystemWebServiceClient webServiceClient = CreateWebServiceClient(); private static volatile bool isClientRegistered; private static volatile string clientHandle; private static readonly Thread eventWatcherThread = new Thread(EventPoller) {IsBackground = true}; #region Constructor // these constructors are hacks to make the C# compiler not mark beforefieldinit // more info: http://www.yoda.arachsys.com/csharp/singleton.html static PhoneSystemWebServiceFactory() { } PhoneSystemWebServiceFactory() { } #endregion #region Properties /// <summary> /// Gets a thread safe instance of PhoneSystemWebServiceFactory /// </summary> public static PhoneSystemWebServiceFactory Instance { get { return instance; } } #endregion #region Private methods /// <summary> /// Create and configure a PhoneSystemWebServiceClient with basic http binding and endpoint from app settings. /// </summary> /// <returns>PhoneSystemWebServiceClient</returns> private static PhoneSystemWebServiceClient CreateWebServiceClient() { string url = ConfigurationManager.AppSettings["PhoneSystemWebService_Url"]; if (string.IsNullOrEmpty(url)) { throw new ConfigurationErrorsException( "The AppSetting \"PhoneSystemWebService_Url\" could not be found. Check the application configuration and ensure that the element exists. Example: <appSettings><add key=\"PhoneSystemWebService_Url\" value=\"http://xyz\" /></appSettings>"); } return new PhoneSystemWebServiceClient(new BasicHttpBinding(), new EndpointAddress(url)); } #endregion #region Event poller public static void EventPoller() { while (true) { if (Thread.CurrentThread.ThreadState == ThreadState.Aborted || Thread.CurrentThread.ThreadState == ThreadState.AbortRequested || Thread.CurrentThread.ThreadState == ThreadState.Stopped || Thread.CurrentThread.ThreadState == ThreadState.StopRequested) break; // get events //webServiceClient.GetEvents(clientHandle, 30, 100); } Thread.Sleep(5000); } #endregion #region Client registration methods private static void RegisterClientIfNeeded() { if (isClientRegistered) { return; } lock (l) { // double lock check if (isClientRegistered) { return; } //clientHandle = webServiceClient.RegisterClient("PhoneSystemWebServiceFactoryInternal", null); isClientRegistered = true; } } private static void UnregisterClient() { if (!isClientRegistered) { return; } lock (l) { // double lock check if (!isClientRegistered) { return; } //webServiceClient.UnegisterClient(clientHandle); } } #endregion #region Phone extension methods public bool SubscribeToEventsForExtension(string extension) { if (monitoredExtensions.Contains(extension)) { return false; } lock (monitoredExtensions.SyncRoot) { // double lock check if (monitoredExtensions.Contains(extension)) { return false; } RegisterClientIfNeeded(); // open line so we receive events for extension LineInfo lineInfo; try { //lineInfo = webServiceClient.OpenLine(clientHandle, extension); } catch (FaultException<PhoneSystemWebSDKErrorDetail>) { // TODO: log error return false; } // add extension to list of monitored extensions //monitoredExtensions.Add(extension, lineInfo.lineID); monitoredExtensions.Add(extension, 1); // start event poller thread if not already started if (eventWatcherThread.ThreadState == ThreadState.Stopped || eventWatcherThread.ThreadState == ThreadState.Unstarted) { eventWatcherThread.Start(); } return true; } } public bool UnsubscribeFromEventsForExtension(string extension) { if (!monitoredExtensions.Contains(extension)) { return false; } lock (monitoredExtensions.SyncRoot) { if (!monitoredExtensions.Contains(extension)) { return false; } // close line try { //webServiceClient.CloseLine(clientHandle, (int) monitoredExtensions[extension]); } catch (FaultException<PhoneSystemWebSDKErrorDetail>) { // TODO: log error return false; } // remove extension from list of monitored extensions monitoredExtensions.Remove(extension); // if we are not monitoring anything else, stop the poller and unregister the client if (monitoredExtensions.Count == 0) { eventWatcherThread.Abort(); UnregisterClient(); } return true; } } public bool IsExtensionMonitored(string extension) { lock (monitoredExtensions.SyncRoot) { return monitoredExtensions.Contains(extension); } } #endregion #region Dispose public void Dispose() { lock (l) { // close any open lines var extensions = monitoredExtensions.Keys.Cast<string>().ToList(); while (extensions.Count > 0) { UnsubscribeFromEventsForExtension(extensions[0]); extensions.RemoveAt(0); } if (!isClientRegistered) { return; } // unregister web service client UnregisterClient(); } } #endregion }

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  • global static boolean pointer causes segmentation fault using pthread

    - by asksw0rder
    New to pthread programming, and stuck on this error when working on a C++&C mixed code. What I have done is to call the c code in the thread created by the c++ code. There is a static boolean pointer used in the thread and should got free when the thread finishes. However I noticed that every time when the program processed into the c function, the value of the boolean pointer would be changed and the segmentation fault then happened due to the free(). Detail code is as follows: static bool *is_center; // omit other codes in between ... void streamCluster( PStream* stream) { // some code here ... while(1){ // some code here ... is_center = (bool*)calloc(points.num,sizeof(bool)); // start the parallel thread here. // the c code is invoked in this function. localSearch(&points,kmin, kmax,&kfinal); // parallel free(is_center); } And the function using parallel is as follows (my c code is invoked in each thread): void localSearch( Points* points, long kmin, long kmax, long* kfinal ) { pthread_barrier_t barrier; pthread_t* threads = new pthread_t[nproc]; pkmedian_arg_t* arg = new pkmedian_arg_t[nproc]; pthread_barrier_init(&barrier,NULL,nproc); for( int i = 0; i < nproc; i++ ) { arg[i].points = points; arg[i].kmin = kmin; arg[i].kmax = kmax; arg[i].pid = i; arg[i].kfinal = kfinal; arg[i].barrier = &barrier; pthread_create(threads+i,NULL,localSearchSub,(void*)&arg[i]); } for ( int i = 0; i < nproc; i++) { pthread_join(threads[i],NULL); } delete[] threads; delete[] arg; pthread_barrier_destroy(&barrier); } Finally the function calling my c code: void* localSearchSub(void* arg_) { // omit some initialize code... // my code begin_papi_thread(&eventSet); // Processing k-means, omit codes. // is_center value will be updated correctly // my code end_papi_thread(&eventSet); // when jumping into this, error happens return NULL; } And from gdb, what I have got for the is_center is: Breakpoint 2, localSearchSub (arg_=0x600000000000bc40) at streamcluster.cpp:1711 1711 end_papi_thread(&eventSet); (gdb) s Hardware watchpoint 1: is_center Old value = (bool *) 0x600000000000bba0 New value = (bool *) 0xa93f3 0x400000000000d8d1 in localSearchSub (arg_=0x600000000000bc40) at streamcluster.cpp:1711 1711 end_papi_thread(&eventSet); Any suggestions? Thanks in advance!

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  • How and why do I set up a C# build machine?

    - by mmr
    Hi all, I'm working with a small (4 person) development team on a C# project. I've proposed setting up a build machine which will do nightly builds and tests of the project, because I understand that this is a Good Thing. Trouble is, we don't have a whole lot of budget here, so I have to justify the expense to the powers that be. So I want to know: What kind of tools/licenses will I need? Right now, we use Visual Studio and Smart Assembly to build, and Perforce for source control. Will I need something else, or is there an equivalent of a cron job for running automated scripts? What, exactly, will this get me, other than an indication of a broken build? Should I set up test projects in this solution (sln file) that will be run by these scripts, so I can have particular functions tested? We have, at the moment, two such tests, because we haven't had the time (or frankly, the experience) to make good unit tests. What kind of hardware will I need for this? Once a build has been finished and tested, is it a common practice to put that build up on an ftp site or have some other way for internal access? The idea is that this machine makes the build, and we all go to it, but can make debug builds if we have to. How often should we make this kind of build? How is space managed? If we make nightly builds, should we keep around all the old builds, or start to ditch them after about a week or so? Is there anything else I'm not seeing here? I realize that this is a very large topic, and I'm just starting out. I couldn't find a duplicate of this question here, and if there's a book out there I should just get, please let me know. EDIT: I finally got it to work! Hudson is completely fantastic, and FxCop is showing that some features we thought were implemented were actually incomplete. We also had to change the installer type from Old-And-Busted vdproj to New Hotness WiX. Basically, for those who are paying attention, if you can run your build from the command line, then you can put it into hudson. Making the build run from the command line via MSBuild is a useful exercise in itself, because it forces your tools to be current.

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  • Coolstack MySQL Crash Unable to Restart

    - by rayblasdel
    Environment: Solaris 10 This mysql server has been up and running for 6 months now. Today all of a sudden it crashed. When typing 'mysql' as user it gives the error MYSQL" Error 2002 (HY000): Can't Connect to Local MySQL server though socket '/tmp/mysql.sock' The server try to open mysql, it stays open for 9-10 seconds and restarts the process. Below are the application logs. Application-database-mysql_mysql-csk.log [ May 30 22:37:52 Enabled. ] [ May 30 22:37:58 Rereading configuration. ] [ May 30 22:37:59 Executing start method ("/opt/coolstack/lib/svc/method/svc-cskmysql start") ] /opt/coolstack/mysql/bin/mysqld_safe --user=mysql --datadir=/dbpool1/data --pid-file=/dbpool1/data/database.soliaonline.com.pid [ May 30 22:37:59 Method "start" exited with status 0 ] [ May 30 22:38:13 Stopping because all processes in service exited. ] [ May 30 22:38:13 Executing stop method ("/opt/coolstack/lib/svc/method/svc-cskmysql stop") ] [ May 30 22:38:13 Method "stop" exited with status 0 ] [ May 30 22:38:13 Executing start method ("/opt/coolstack/lib/svc/method/svc-cskmysql start") ] /opt/coolstack/mysql/bin/mysqld_safe --user=mysql --datadir=/dbpool1/data --pid-file=/dbpool1/data/database.soliaonline.com.pid [ May 30 22:38:13 Method "start" exited with status 0 ] [ May 30 22:38:25 Stopping because all processes in service exited. ] [ May 30 22:38:25 Executing stop method ("/opt/coolstack/lib/svc/method/svc-cskmysql stop") ] [ May 30 22:38:25 Method "stop" exited with status 0 ] I am hoping someone might have run into this before and might know how to fix it. The following is an excerpt from the MySQL Error log 100530 22:44:03 mysqld_safe mysqld from pid file /dbpool1/data/database.soliaonline.com.pid ended 100530 22:44:04 mysqld_safe Starting mysqld daemon with databases from /dbpool1/data InnoDB: Log scan progressed past the checkpoint lsn 32 727170612 100530 22:44:13 InnoDB: Database was not shut down normally! InnoDB: Starting crash recovery. InnoDB: Reading tablespace information from the .ibd files... InnoDB: Restoring possible half-written data pages from the doublewrite InnoDB: buffer... InnoDB: Doing recovery: scanned up to log sequence number 32 727200901 100530 22:44:14 InnoDB: Starting an apply batch of log records to the database... InnoDB: Progress in percents: 100530 22:44:14 - mysqld got signal 11 ; This could be because you hit a bug. It is also possible that this binary or one of the libraries it was linked against is corrupt, improperly built, or misconfigured. This error can also be caused by malfunctioning hardware. We will try our best to scrape up some info that will hopefully help diagnose the problem, but since we have already crashed, something is definitely wrong and this may fail. key_buffer_size=209715200 read_buffer_size=1048576 max_used_connections=0 max_threads=10000 threads_connected=0 It is possible that mysqld could use up to key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 31024253 K bytes of memory Hope that's ok; if not, decrease some variables in the equation. enter code here

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  • Performance of SHA-1 Checksum from Android 2.2 to 2.3 and Higher

    - by sbrichards
    In testing the performance of: package com.srichards.sha; import android.app.Activity; import android.os.Bundle; import android.widget.TextView; import java.io.IOException; import java.io.InputStream; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; import com.srichards.sha.R; public class SHAHashActivity extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); TextView tv = new TextView(this); String shaVal = this.getString(R.string.sha); long systimeBefore = System.currentTimeMillis(); String result = shaCheck(shaVal); long systimeResult = System.currentTimeMillis() - systimeBefore; tv.setText("\nRunTime: " + systimeResult + "\nHas been modified? | Hash Value: " + result); setContentView(tv); } public String shaCheck(String shaVal){ try{ String resultant = "null"; MessageDigest digest = MessageDigest.getInstance("SHA1"); ZipFile zf = null; try { zf = new ZipFile("/data/app/com.blah.android-1.apk"); // /data/app/com.blah.android-2.apk } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } ZipEntry ze = zf.getEntry("classes.dex"); InputStream file = zf.getInputStream(ze); byte[] dataBytes = new byte[32768]; //65536 32768 int nread = 0; while ((nread = file.read(dataBytes)) != -1) { digest.update(dataBytes, 0, nread); } byte [] rbytes = digest.digest(); StringBuffer sb = new StringBuffer(""); for (int i = 0; i< rbytes.length; i++) { sb.append(Integer.toString((rbytes[i] & 0xff) + 0x100, 16).substring(1)); } if (shaVal.equals(sb.toString())) { resultant = ("\nFalse : " + "\nFound:\n" + sb.toString() + "|" + "\nHave:\n" + shaVal); } else { resultant = ("\nTrue : " + "\nFound:\n" + sb.toString() + "|" + "\nHave:\n" + shaVal); } return resultant; } catch (IOException e) { e.printStackTrace(); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } return null; } } On a 2.2 Device I get average runtime of ~350ms, while on newer devices I get runtimes of 26-50ms which is substantially lower. I'm keeping in mind these devices are newer and have better hardware but am also wondering if the platform and the implementation affect performance much and if there is anything that could reduce runtimes on 2.2 devices. Note, the classes.dex of the .apk being accessed is roughly 4MB. Thanks!

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  • How is "clean" testing done on the Macintosh without virtualization?

    - by Schnapple
    One of the things I've run across on Windows is when a web browser plugin or program you're developing makes an assumption that something is installed that, by default, isn't always present on Windows. A perfect example would be .NET - a whole lot of people running Windows XP have never installed any versions of .NET and so the installer needs to detect and remedy this if necessary. The way I've been testing this in Windows is to have a virtual machine with a snapshot of a clean, patched, but otherwise untouched install of XP or Vista or 7 or whatever. When I'm done testing I just discard any changes since the snapshot. Works great. I'm now developing something for the Macintosh, a platform which is very new to me, and I'm seeing that virtualization does not appear to be an option. It's explicitly forbidden in the EULA of Mac OS X, it's only allowed from Mac OS X Server, which seeing as how I'm targeting an end product is of no use to me, and the one program I see which can virtualize it - VirtualBox - only supports the server and actively nukes any discussion of running the consumer/client version of Mac OS X. And the only instructions I find anywhere on the topic seem to involve the use of "hacking" programs which is very much incompatible with the full-time gig I'm trying to do this for. So it looks like virtualization is out, but at various points I'm going to want or need to simulate what it's like to install and run this software on a "clean" Macintosh. How do people usually do this? Just buy multiple Macintoshes and use Time Machine? Am I thinking about this all wrong and everything Just Works? To be clear I'm not trying to run Mac OS X on a Windows machine. I have a Macintosh, I'm fine with virtualizing Mac OS X on Apple hardware, I'm just not seeing a route to making the non-Server version do this. I'm aware that Mac OS X Server can be virtualized but that's not what I'm going for. I'm aware that there are unsanctioned/unsupported methods of making Mac OS X run in virtualization programs like VirtualBox but for legal reasons I am not interested in those. My question is not "how can I do this?" but rather "so this thing I do on Windows seems to not be possible, generally, on the Macintosh, so what do people do to achieve what I'm going for?"

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  • jQuery: modify href attribute for first level list only

    - by bloggerious
    I'm a noob in jQuery and have stuck at this. I have the following HTML code output from a PHP page: <ul class="cats"> <li><span><a href="cant_post_link_yet1">Lifestyle</a></span></li> <li><span><a href="cant_post_link_yet2">Entertainment</a></span></li> <li class="has_child"> <span><a href="cant_post_link_yet3">Technology</a></span> <ul class="subcats"> <li><span><a href="cant_post_link_yet4">Gadgets</a></span></li> <li><span><a href="cant_post_link_yet5">Hardware</a></span></li> </ul> </li> <li><span><a href="cant_post_link_yetsports">Sports</a></span></li> <li class="has_child"> <span><a href="cant_post_link_yet6">Design</a></span> <ul class="subcats"> <li class="has_child"> <span><a href="cant_post_link_yet7">Web Design</a></span> <ul class="subcat"> <li><span><a href="cant_post_link_yet8">Adobe Photoshop</a></span></li> </ul> </li> <li><span><a href="cant_post_link_yet9">Graphics and Print</a></span></li> </ul> </li> What's the correct jQuery code so that I can modify the href attribute for the first-level list only? Basically, I want to change the href of Technology and Design to be "#" but will not change the href of Web Design which is already on second-level list. More Info: In the code above, if list has subcategories, then it has the class has_child, whether it's on first-level or not. So I want only the first-level list which has class has_child to be modified the href to "#" I can't alter output anymore because it's in the PHP code. Any help is greatly appreciated.

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  • Separate specific #ifdef branches

    - by detly
    In short: I want to generate two different source trees from the current one, based only on one preprocessor macro being defined and another being undefined, with no other changes to the source. If you are interested, here is my story... In the beginning, my code was clean. Then we made a new product, and yea, it was better. But the code saw only the same peripheral devices, so we could keep the same code. Well, almost. There was one little condition that needed to be changed, so I added: #if defined(PRODUCT_A) condition = checkCat(); #elif defined(PRODUCT_B) condition = checkCat() && checkHat(); #endif ...to one and only one source file. In the general all-source-files-include-this header file, I had: #if !(defined(PRODUCT_A)||defined(PRODUCT_B)) #error "Don't make me replace you with a small shell script. RTFM." #endif ...so that people couldn't compile it unless they explicitly defined a product type. All was well. Oh... except that modifications were made, components changed, and since the new hardware worked better we could significantly re-write the control systems. Now when I look upon the face of the code, there are more than 60 separate areas delineated by either: #ifdef PRODUCT_A ... #else ... #endif ...or the same, but for PRODUCT_B. Or even: #if defined(PRODUCT_A) ... #elif defined(PRODUCT_B) ... #endif And of course, sometimes sanity took a longer holiday and: #ifdef PRODUCT_A ... #endif #ifdef PRODUCT_B ... #endif These conditions wrap anywhere from one to two hundred lines (you'd think that the last one could be done by switching header files, but the function names need to be the same). This is insane. I would be better off maintaining two separate product-based branches in the source repo and porting any common changes. I realise this now. Is there something that can generate the two different source trees I need, based only on PRODUCT_A being defined and PRODUCT_B being undefined (and vice-versa), without touching anything else (ie. no header inclusion, no macro expansion, etc)?

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  • Opening Macro definitions: tdfx_span.c: lvalue required as left operand of assignment

    - by anttir
    Hi, I'm trying to compile X11R6-7.0 under Ubuntu maverick and got some weird compilation errors I'm unable to resolve myself. I needed X11R6-7.0 as ati catalyst drivers don't support newer xorg and oss drivers don't support 3d acceleration of my hardware. Anyone know what this error message means? I know some C but I got a bit confused. Does it mean GET_FB_DATA macro returned NULL or some method/property not set? Any further insight how to "debug" preprocessor definitions at this point would be great. I don't think I can print anything useful with #error. The error I get: tdfx_span.c: In function ‘tdfxDDWriteDepthPixels’: tdfx_span.c:976: error: lvalue required as left operand of assignment tdfx_span.c:1008: error: lvalue required as left operand of assignment tdfx_span.c: In function ‘write_stencil_pixels’: tdfx_span.c:1242: error: lvalue required as left operand of assignment the Code: 958- switch (depth_size) { 959- case 16: 960- GetBackBufferInfo(fxMesa, &backBufferInfo); 961- /* 962- * Note that the _LOCK macro adds a curly brace, 963- * and the UNLOCK macro removes it. 964- */ 965- WRITE_FB_SPAN_LOCK(fxMesa, info, 966- GR_BUFFER_AUXBUFFER, GR_LFBWRITEMODE_ANY); 967- { 968- LFBParameters ReadParams; 969- GetFbParams(fxMesa, &info, &backBufferInfo, 970- &ReadParams, sizeof(GLushort)); 971- for (i = 0; i < n; i++) { 972- if (mask[i] && visible_pixel(fxMesa, x[i], y[i])) { 973- xpos = x[i] + fxMesa->x_offset; 974- ypos = bottom - y[i]; 975- d16 = depth[i]; 976: PUT_FB_DATA(&ReadParams, GLushort, xpos, ypos, d16); 977- } 978- } 979- } 980- WRITE_FB_SPAN_UNLOCK(fxMesa, GR_BUFFER_AUXBUFFER); 981- break; 982- case 24: And relative macros: #define GET_FB_DATA(ReadParamsp, type, x, y) \ (((x) < (ReadParamsp)->firstWrappedX) \ ? (((type *)((ReadParamsp)->lfbPtr)) \ [(y) * ((ReadParamsp)->LFBStrideInElts) \ + (x)]) \ : (((type *)((ReadParamsp)->lfbWrapPtr)) \ [((y)) * ((ReadParamsp)->LFBStrideInElts) \ + ((x) - (ReadParamsp)->firstWrappedX)])) #define GET_ORDINARY_FB_DATA(ReadParamsp, type, x, y) \ (((type *)((ReadParamsp)->lfbPtr)) \ [(y) * ((ReadParamsp)->LFBStrideInElts) \ + (x)]) #define GET_WRAPPED_FB_DATA(ReadParamsp, type, x, y) \ (((type *)((ReadParamsp)->lfbWrapPtr)) \ [((y)) * ((ReadParamsp)->LFBStrideInElts) \ + ((x) - (ReadParamsp)->firstWrappedX)]) #define PUT_FB_DATA(ReadParamsp, type, x, y, value) \ (GET_FB_DATA(ReadParamsp, type, x, y) = (type)(value)) #define PUT_ORDINARY_FB_DATA(ReadParamsp, type, x, y, value) \ (GET_ORDINARY_FB_DATA(ReadParamsp, type, x, y) = (type)(value)) #define PUT_WRAPPED_FB_DATA(ReadParamsp, type, x, y, value) \ (GET_WRAPPED_FB_DATA(ReadParamsp, type, x, y) = (type)(value)) The LFBParameters Struct 483-typedef struct 484-{ 485- void *lfbPtr; 486- void *lfbWrapPtr; 487- FxU32 LFBStrideInElts; 488- GLint firstWrappedX; 489-} 490:LFBParameters; Thanks for looking.

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  • Creating multiple heads in remote repository

    - by Jab
    We are looking to move our team (~10 developers) from SVN to mercurial. We are trying to figure out how to manage our workflow. In particular, we are trying to see if creating remote heads is the right solution. We currently have a very large repository with multiple, related projects. They share a lot of code, but pieces of the project are deployed by different teams (3 teams) independent of other portions of the code-base. So each team is working on concurrent large features. The way we currently handles this in SVN are branches. Team1 has a branch for Feature1, same deal for the other teams. When Team1 finishes their change, it gets merged into the trunk and deployed out. The other teams follow suite when their project is complete, merging of course. So my initial thought are using Named Branches for these situations. Team1 makes a Feature1 branch off of the default branch in Hg. Now, here is the question. Should the team PUSH that branch, in it's current/half-state to the repository. This will create a second head in the core repo. My initial reaction was "NO!" as it seems like a bad idea. Handling multiple heads on our repository just sounds awful, but there are some advantages... First, the teams want to setup Continuous Integration to build this branch during their development cycle(months long). This will only work if the CI can pull this branch from the repo. This is something we do now with SVN, copy a CI build and change the branch. Easy. Second, it makes it easier for any team member to jump onto the branch and start working. Without pushing to the core repo, they would have to receive a push from a developer on that team with the changeset information. It is also possible to lose local commits to hardware failure. The chances increase a lot if it's a branch by a single developer who has followed the "don't push until finished" approach. And lastly is just for ease of use. The developers can easily just commit and push on their branch at any time without consequence(as they do today, in their SVN branches). Is there a better way to handle this scenario that I may be missing? I just want a veteran's opinion before moving forward with the strategy. For bug fixes we like the general workflow of mecurial, anonymous branches that only consist of 1-2 commits. The simplicity is great for those cases. By the way, I've read this , great article which seems to favor Named branches.

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  • Remote XP -> Win98 WMI Connection

    - by Logan Young
    I've asked this on Technet, but because Win98 is no longer supported, I can't get any decent information, I was hoping there might be some "old school" developers here who might be able to help me. There is an application that we use a lot at work. This application should run 8am-5pm with as little interruption as possible. Most of the computers where this application runs are using Win98, and we have no way to upgrade them because we can't buy new hardware at the moment. My computer is running WinXP, so I thought of a way to make sure that this application runs all the time: The idea I had was to develop a Windows Service that executes a VBScript file that contains a WMI query to get a list of processes from each computer. Each list is then examined, and, depending on whether or not the target application is running, it will either do nothing, or it will execute another VBScript file that contains a WMI query that will be used to start the target application remotely. I later found a way to do this all with 1 VBScript file (see code below) My problem is in the remote connection to the target computers. I've installed WMI Core 1.5 on them, but every time I try the remote connection, I get the following: The remote server is unavailable or does not exist: 'GetObject' VBScript runtime error 800A01CE I've done some research, and all I've found is info about DCOM Config and Windows Firewall, but Win98 doesn't have either of these. ' #### Variables and constants #### Const HIDDEN_WINDOW = 12 Dim T ' #### End Variables and constants #### Main() Sub Main() ' #### Get Process information from WMI Computer = "." Set WMI = GetObject("winmgmts:" & _ "{ImpersonationLevel=Impersonate}!\\" & Computer & "\root\cimv2") Set Settings = WMI.ExecQuery("SELECT * FROM Win32_Process") For Each Process In Settings ' #### If the application is found to be running, set a value to indicate this If Process.Name = "NOTEPAD.EXE" Then T = True End If Next ' #### T will only have a value if the application is not running. We therefore ' #### evaluate it to determine if it has a value or not. If not, start the application If Not T Then 'MsgBox("Application not found.") Set Startup = WMI.Get("Win32_ProcessStartup") Set Config = Startup.SpawnInstance_ Config.ShowWindow = HIDDEN_WINDOW Set Process = GetObject("winmgmts:root\cimv2:Win32_Process") errReturn = Process.Create(_ "C:\Windows\notepad.exe", null, Config, intProcessID) End If End Sub This uses WMI to get the list of processes from the local computer and, if the target application is running, it'll do nothing, otherwise it'll forcefully start the target application. The problem is that this works only if I specify the local comuter, if I target another computer, I get the error mentioned above. Does anyone have any ideas? Thanks in advance for the help!

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  • Technical non-terminating condition in a loop

    - by Snarfblam
    Most of us know that a loop should not have a non-terminating condition. For example, this C# loop has a non-terminating condition: any even value of i. This is an obvious logic error. void CountByTwosStartingAt(byte i) { // If i is even, it never exceeds 254 for(; i < 255; i += 2) { Console.WriteLine(i); } } Sometimes there are edge cases that are extremely unlikeley, but technically constitute non-exiting conditions (stack overflows and out-of-memory errors aside). Suppose you have a function that counts the number of sequential zeros in a stream: int CountZeros(Stream s) { int total = 0; while(s.ReadByte() == 0) total++; return total; } Now, suppose you feed it this thing: class InfiniteEmptyStream:Stream { // ... Other members ... public override int Read(byte[] buffer, int offset, int count) { Array.Clear(buffer, offset, count); // Output zeros return count; // Never returns -1 (end of stream) } } Or more realistically, maybe a stream that returns data from external hardware, which in certain cases might return lots of zeros (such as a game controller sitting on your desk). Either way we have an infinite loop. This particular non-terminating condition stands out, but sometimes they don't. A completely real-world example as in an app I'm writing. An endless stream of zeros will be deserialized into infinite "empty" objects (until the collection class or GC throws an exception because I've exceeded two billion items). But this would be a completely unexpected circumstance (considering my data source). How important is it to have absolutely no non-terminating conditions? How much does this affect "robustness?" Does it matter if they are only "theoretically" non-terminating (is it okay if an exception represents an implicit terminating condition)? Does it matter whether the app is commercial? If it is publicly distributed? Does it matter if the problematic code is in no way accessible through a public interface/API? Edit: One of the primary concerns I have is unforseen logic errors that can create the non-terminating condition. If, as a rule, you ensure there are no non-terminating conditions, you can identify or handle these logic errors more gracefully, but is it worth it? And when? This is a concern orthogonal to trust.

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  • How do I add "Press any key to boot from usb" when installing Windows from a flash drive? (Grub4dos question / how to remove a bootloader)

    - by Vincent
    Hi there! I've been struggling with this problem for a while now and finially decided to ask for help. Let me first explain what the main purpose of the app is: to provide the a very easy to use way of backing up files, after which I format the drive and start Windows 7 setup. I do this by booting WinPE, which runs a script to detect Windows installations and then opens a file browser. After the file browser is closed, the script continues and formats the drive that contains the Windows installation, and starts an unattended Windows 7 install. Now here is the problem: When you start Windows setup or WinPE from a dvd, you get a nice option to "Press any key to boot from DVD". This is to prevent the computer from booting the DVD when the first phase of the installation is complete and the computer reboots. However, when booting from a flash drive, Windows does not provide this option: it simply boots the flash drive every reboot. To replicate the "press any key" function, I installed Grub4Dos, which works great. It provides a small menu, the first standard item being "Continue installation", the second being "start installation". After quite a lot of tweaking, I got everything working: Start installation starts WinPE, which in turn starts the Windows installation. At first reboot, the Grub4Dos menu comes up, counts 5 seconds and boots the second stage of the installation. Here, I am greeted with the error: "Windows setup could not configure windows to run on this computer's hardware." When I boot into WinPE the normal way (put the bootmgr on the stick root) and change my bios to boot from the primary hdd after first reboot, I don't get this error. I've been looking around, and the only thing I could find was that the BIOS automatically names the boot device hd0, and that Windows can only be run / installed to hd 0. I'm not sure if this is the problem. I read about remapping to solve this problem, but to do that you have to know the phisical location of the hard drive and partition, like hd(0,1). I want this flash drive to work on any PC, regardless of where the OS is installed, so that's not really a possibility. A possible fix I thought of is removing the bootloader from the flash drive when I'm in WinPE. That way, when the pc reboots the BIOS will not see the flash drive as a boot drive and instead boot the primary hdd. I have yet to find a way to do this. Thank you for reading my question, and if you have any suggestion, please do.

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