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  • Recording Available - Features and Functions Payments Module

    - by MHundal
    The Payments Module recording provides a high-level overview of Payments Processing in ETPM.  The recording discusses the Payments Data Model, including Payment Events, Tenders, Tender Control, Deposit and Deposit Control.  In addition, there is a product demonstration of payment processing in the system. Payments Module Overview:  https://oracletalk.webex.com/oracletalk/ldr.php?AT=pb&SP=MC&rID=67364002&rKey=9fe755e4f41a2d4d

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  • Ubuntu 12.04 updates fail recently - Please help

    - by user74152
    I upgraded Ubuntu 11.10 to 12.04 LTS immediately after its release (april 2012). Since then updates (new kernels and others) succeeded regularly, but recently, suddenly, updates fail consistently. What causes the problem and how can it be solved? Terminal information after the last update attempt: ariel@ariel-MS-7592:~$ sudo apt-get upgrade Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. 3 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Do you want to continue [Y/n]? y Setting up linux-image-3.2.0-26-generic (3.2.0-26.41) ... Running depmod. update-initramfs: deferring update (hook will be called later) Examining /etc/kernel/postinst.d. run-parts: executing /etc/kernel/postinst.d/dkms 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic run-parts: executing /etc/kernel/postinst.d/initramfs-tools 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic update-initramfs: Generating /boot/initrd.img-3.2.0-26-generic run-parts: executing /etc/kernel/postinst.d/pm-utils 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic run-parts: executing /etc/kernel/postinst.d/update-notifier 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic run-parts: executing /etc/kernel/postinst.d/zz-update-grub 3.2.0-26-generic /boot/vmlinuz-3.2.0-26-generic /usr/sbin/grub-mkconfig: 11: /etc/default/grub: splash”: not found run-parts: /etc/kernel/postinst.d/zz-update-grub exited with return code 127 Failed to process /etc/kernel/postinst.d at /var/lib/dpkg/info/linux-image-3.2.0-26-generic.postinst line 1010. dpkg: error processing linux-image-3.2.0-26-generic (--configure): subprocess installed post-installation script returned error exit status 2 No apport report written because MaxReports is reached already dpkg: dependency problems prevent configuration of linux-image-generic: linux-image-generic depends on linux-image-3.2.0-26-generic; however: Package linux-image-3.2.0-26-generic is not configured yet. dpkg: error processing linux-image-generic (--configure): dependency problems - leaving unconfigured dpkg: dependency problems prevent configuration of linux-generic: linux-generic depends on linux-image-generic (= 3.2.0.26.28); however: Package linux-image-generic is not configured yet. dpkg: error processing linux-generic (--configure): dependency problems - leaving unconfiguredNo apport report written because MaxReports is reached already No apport report written because MaxReports is reached already Errors were encountered while processing: linux-image-3.2.0-26-generic linux-image-generic linux-generic E: Sub-process /usr/bin/dpkg returned an error code (1)

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  • How can i install .deb files from terminal , i tried different ways in askubuntu

    - by krishnamraju
    i am trying to install teamviewer and i am getting the following error and the entire process is as follows kittu@kittu-355V4C-356V4C-3445VC-3545VC:~$ sudo dpkg -i teamviewer_linux_x64.debdpkg: error processing archive teamviewer_linux_x64.deb (--install): cannot access archive: No such file or directory Errors were encountered while processing: teamviewer_linux_x64.deb the file is in home/downloads/teamviewer_linux_x64.deb

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  • RTMPDUMPTV problem

    - by ranavita
    (Reading database ... 459988 files and directories currently installed.) Unpacking librtmp-dev (from .../librtmp-dev_2.4~20110711.gitc28f1bab-1_amd64.deb) ... dpkg: error processing /var/cache/apt/archives/librtmp-dev_2.4~20110711.gitc28f1bab-1_amd64.deb (--unpack): trying to overwrite '/usr/include/librtmp/amf.h', which is also in package rtmpdump 2.5-0ubuntu2~precise Errors were encountered while processing: /var/cache/apt/archives/librtmp-dev_2.4~20110711.gitc28f1bab-1_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1) above error code results after running sudo apt-get install -f A I am trying to fix the broken package of rtmptv

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  • Why does Ubuntu 12.10 only see 8 cores?

    - by tunnuz
    In our lab we just bought a new machine with two 8-cores Intel(R) Xeon(R) CPU E5-2660 0 @ 2.20GHz processors which also support Hyper-Threading. I would expect Ubuntu to see 32 processing units, however it only detects 8 of them (the equivalent of just one processor with Hyper-Threading disabled). The bios correctly reports a total of 32 processing units. I am using Ubuntu 12.10 desktop 32 bit. Any idea about how to solve this?

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  • On Handling Dates in SQL

    The calendar is inherently complex by the very nature of the astronomy that underlies the year, and the conflicting historical conventions. The handling of dates in TSQL is even more complex because, when SQL Server was Sybase, it was forced by the lack of prevailing standards in SQL to create its own ways of processing and formatting dates and times. Joe Celko looks forward to a future when it is possible to write standard SQL date-processing code with SQL Server.

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  • Installing WINE 1.4 Errors on Precise 12.04

    - by user71965
    This message is consistently received when installing WINE1.4, which fails to install properly update-initramfs: Generating /boot/initrd.img-3.2.0-25-generic-pae Fatal: No images have been defined. run-parts: /etc/initramfs/post-update.d//runlilo exited with return code 1 dpkg: error processing initramfs-tools (--configure): subprocess installed post-installation script returned error exit status 1 Errors were encountered while processing: initramfs-tools Any thoughts appreciated.

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  • Why does my Messaging Menu code not work when split into functions?

    - by fluteflute
    Below are two python programs. They're exactly the same, except for one is split into two functions. However only the one that's split into two functions doesn't work - the second function doesn't work. Why would this be? Note the code is taken from this useful blog post. Without functions (works): import gtk def show_window_function(x, y): print x print y # get the indicate module, which does all the work import indicate # Create a server item mm = indicate.indicate_server_ref_default() # If someone clicks your server item in the MM, fire the server-display signal mm.connect("server-display", show_window_function) # Set the type of messages that your item uses. It's not at all clear which types # you're allowed to use, here. mm.set_type("message.im") # You must specify a .desktop file: this is where the MM gets the name of your # app from. mm.set_desktop_file("/usr/share/applications/nautilus.desktop") # Show the item in the MM. mm.show() # Create a source item mm_source = indicate.Indicator() # Again, it's not clear which subtypes you are allowed to use here. mm_source.set_property("subtype", "im") # "Sender" is the text that appears in the source item in the MM mm_source.set_property("sender", "Unread") # If someone clicks this source item in the MM, fire the user-display signal mm_source.connect("user-display", show_window_function) # Light up the messaging menu so that people know something has changed mm_source.set_property("draw-attention", "true") # Set the count of messages in this source. mm_source.set_property("count", "15") # If you prefer, you can set the time of the last message from this source, # rather than the count. (You can't set both.) This means that instead of a # message count, the MM will show "2m" or similar for the time since this # message arrived. # mm_source.set_property_time("time", time.time()) mm_source.show() gtk.mainloop() With functions (second function is executed but doesn't actually work): import gtk def show_window_function(x, y): print x print y # get the indicate module, which does all the work import indicate def function1(): # Create a server item mm = indicate.indicate_server_ref_default() # If someone clicks your server item in the MM, fire the server-display signal mm.connect("server-display", show_window_function) # Set the type of messages that your item uses. It's not at all clear which types # you're allowed to use, here. mm.set_type("message.im") # You must specify a .desktop file: this is where the MM gets the name of your # app from. mm.set_desktop_file("/usr/share/applications/nautilus.desktop") # Show the item in the MM. mm.show() def function2(): # Create a source item mm_source = indicate.Indicator() # Again, it's not clear which subtypes you are allowed to use here. mm_source.set_property("subtype", "im") # "Sender" is the text that appears in the source item in the MM mm_source.set_property("sender", "Unread") # If someone clicks this source item in the MM, fire the user-display signal mm_source.connect("user-display", show_window_function) # Light up the messaging menu so that people know something has changed mm_source.set_property("draw-attention", "true") # Set the count of messages in this source. mm_source.set_property("count", "15") # If you prefer, you can set the time of the last message from this source, # rather than the count. (You can't set both.) This means that instead of a # message count, the MM will show "2m" or similar for the time since this # message arrived. # mm_source.set_property_time("time", time.time()) mm_source.show() function1() function2() gtk.mainloop()

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  • How to diagnose and solve an erratic "HDCP Support Required"?

    - by Jom Orgstrom
    I am playing a digital tv broadcast on Windows Media Center for Windows 7. I built this system so it works with HDCP, and in fact I have been able to watch tv and bluray before with this same computer. However, I suddenly started getting an "HDCP Support Required" error from WMC. The entire message is as follows: HDCP Support Required High-bandwidth Digital Content Protection (HDCP) may not be supported by the current video card. Use an HDCP-compliant display, video card, and video driver. Or, connect using an analog connection such as component or VGA. Relevant specs are: CPU: Ivy Bridge Core i7-3770 Motherboard: Asus P8H77-I Memory: 16GB DDR3-1600 Graphics: Radeon HD 7850 (Driver by AMD, version 8.982.0.0 built on 2012/07/27) Display: Acer P243w connected by HDMI Sound: Roland Quad-Capture (It complains even when I use the bundled VIA HD Audio) TV Tuner: I-O Data GV-MC7/HZ3 OS: Windows 7 Professional SP1, Windows Update enabled. All patched and up to date. As you can see, there is nothing weird or old about my setup. I am also not doing anything strange, not doing any overclocking, weird system changes and so on. One thing that does happen from time to time, is that the display goes black for a few seconds (sometimes when watching media contents, sometimes when just using photoshop or Visual Studio). This happened with my previous setup as well, so I'd be inclined to think it is a display or cable issue (apart from the BD drive, these are the only things I kept from my previous setup to this one). But being a digital transfer, as far as I know, these things either work or not. Never erratically or with decreased quality. The thing is that sometimes I can watch the TV, sometimes not. This happens with recorded programs as well, so it's not a per-program thing. Sometimes rebooting helps, sometimes it doesn't. Sometimes unplugging and plugging back the HDMI connector helps, sometimes it doesn't. Sometimes doing so doesn't even turn the screen back on, so I have to reboot. Unfortunately, WMC's error message is quite unhelpful. I'd like to know exactly where the problem is, so I can solve it. I don't want to buy a brand new display just to then find out it was a registry setting that was misconfigured. I've tried looking at the system event viewer, but these errors don't show up at all in there. Other people who have this problem seem to have a setup that is not HDCP compliant, so I turn to you guys here. Anybody knows how to diagnose this problem? Edit: So I got the Cyberlink Blu-ray disc advisor. I ran it and told me everything was okay, except for the Video Connection Type, which showed as "Digital (without HDCP)". I then proceeded to unplug the power cable from the monitor, plugged it in again, ran the tool again, and now it's "Digital (with HDCP)". Needless to say, I can watch my TV and recorded programs on WMP again. I'm guessing that at some point, something may be slightly wrong with the HDCP setup, and Windows decides to reset the entire content protection path (which leads to the screen blanking out). Usually the reset succeeds, but sometimes it doesn't, so Windows defaults to turning HDCP off. There's no way to turn it back on, except by doing a hard reset of the display. I really want to know what the exact error was, so I can fix it. Is it the cable? is it the display? is it the video card? the driver? Also, is there any other way to try and turn HDCP on again without having to hard reset the display? Oh, questions, questions...

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  • How would i down-sample a .wav file then reconstruct it using nyquist? - in matlab [closed]

    - by martin
    Possible Duplicate: How would i down-sample a .wav file then reconstruct it using nyquist? - in matlab This is all done in MatLab 2010 My objective is to show the results of: undersampling, nyquist rate/ oversampling First i need to downsample the .wav file to get an incomplete/ or impartial data stream that i can then reconstuct. Heres the flow chart of what im going to be doing So the flow is analog signal - sampling analog filter - ADC - resample down - resample up - DAC - reconstruction analog filter what needs to be achieved: F= Frequency F(Hz=1/s) E.x. 100Hz = 1000 (Cyc/sec) F(s)= 1/(2f) Example problem: 1000 hz = Highest frequency 1/2(1000hz) = 1/2000 = 5x10(-3) sec/cyc or a sampling rate of 5ms This is my first signal processing project using matlab. what i have so far. % Fs = frequency sampled (44100hz or the sampling frequency of a cd) [test,fs]=wavread('test.wav'); % loads the .wav file left=test(:,1); % Plot of the .wav signal time vs. strength time=(1/44100)*length(left); t=linspace(0,time,length(left)); plot(t,left) xlabel('time (sec)'); ylabel('relative signal strength') **%this is were i would need to sample it at the different frequecys (both above and below and at) nyquist frequency.*I think.*** soundsc(left,fs) % shows the resaultant audio file , which is the same as original ( only at or above nyquist frequency however) Can anyone tell me how to make it better, and how to do the various sampling at different frequencies?

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  • Annoying Twisted Python problem

    - by Kalmi
    I'm trying to answer the following question out of personal interest: What is the fastest way to send 100,000 HTTP requests in Python? And this is what I have came up so far, but I'm experiencing something very stange. When installSignalHandlers is True, it just hangs. I can see that the DelayedCall instances are in reactor._newTimedCalls, but processResponse never gets called. When installSignalHandlers is False, it throws an error and works. from twisted.internet import reactor from twisted.web.client import Agent from threading import Semaphore, Thread import time concurrent = 100 s = Semaphore(concurrent) reactor.suggestThreadPoolSize(concurrent) t=Thread( target=reactor.run, kwargs={'installSignalHandlers':True}) t.daemon=True t.start() agent = Agent(reactor) def processResponse(response,url): print response.code, url s.release() def processError(response,url): print "error", url s.release() def addTask(url): req = agent.request('HEAD', url) req.addCallback(processResponse, url) req.addErrback(processError, url) for url in open('urllist.txt'): addTask(url.strip()) s.acquire() while s._Semaphore__value!=concurrent: time.sleep(0.1) reactor.stop() And here is the error that it throws when installSignalHandlers is True: (Note: This is the expected behaviour! The question is why it doesn't work when installSignalHandlers is False.) Traceback (most recent call last): File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 396, in fireEvent DeferredList(beforeResults).addCallback(self._continueFiring) File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 224, in addCallback callbackKeywords=kw) File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 213, in addCallbacks self._runCallbacks() File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 371, in _runCallbacks self.result = callback(self.result, *args, **kw) --- <exception caught here> --- File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 409, in _continueFiring callable(*args, **kwargs) File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 1165, in _reallyStartRunning self._handleSignals() File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 1105, in _handleSignals signal.signal(signal.SIGINT, self.sigInt) exceptions.ValueError: signal only works in main thread What am I doing wrong and what is the right way? I'm new to twisted.

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  • When does a PHP <5.3.0 daemon script receive signals?

    - by MidnightLightning
    I've got a PHP script in the works that is a job worker; its main task is to check a database table for new jobs, and if there are any, to act on them. But jobs will be coming in in bursts, with long gaps in between, so I devised a sleep cycle like: while(true) { if ($jobs = get_new_jobs()) { // Act upon the jobs } else { // No new jobs now sleep(30); } } Good, but in some cases that means there might be a 30 second lag before a new job is acted upon. Since this is a daemon script, I figured I'd try the pcntl_signal hook to catch a SIGUSR1 signal to nudge the script to wake up, like: $_isAwake = true; function user_sig($signo) { global $_isAwake; daemon_log("Caught SIGUSR1"); $_isAwake = true; } pcntl_signal(SIGUSR1, 'user_sig'); while(true) { if ($jobs = get_new_jobs()) { // Act upon the jobs } else { // No new jobs now daemon_log("No new jobs, sleeping..."); $_isAwake = false; $ts = time(); while(time() < $ts+30) { sleep(1); if ($_isAwake) break; // Did a signal happen while we were sleeping? If so, stop sleeping } $_isAwake = true; } } I broke the sleep(30) up into smaller sleep bits, in case a signal doesn't interrupt a sleep() command, thinking that this would cause at most a one-second delay, but in the log file, I'm seeing that the SIGUSR1 isn't being caught until after the full 30 seconds has passed (and maybe the outer while loop resets). I found the pcntl_signal_dispatch command, but that's only for PHP 5.3 and higher. If I were using that version, I could stick a call to that command before the if ($_isAwake) call, but as it currently stands I'm on 5.2.13. On what sort of situations is the signals queue interpreted in PHP versions without the means to explicitly call the queue parsing? Could I put in some other useless command in that sleep loop that would trigger a signal queue parse within there?

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  • reactor not working when reactor.run is not called in the main thread and installSignalHandlers=Fals

    - by Kalmi
    I'm trying to answer the following question out of personal interest: What is the fastest way to send 100,000 HTTP requests in Python? And this is what I have came up so far, but I'm experiencing something very stange. When installSignalHandlers is True, it just hangs. I can see that the DelayedCall instances are in reactor._newTimedCalls, but processResponse never gets called. When installSignalHandlers is False, it throws an error and works. from twisted.internet import reactor from twisted.web.client import Agent from threading import Semaphore, Thread import time concurrent = 100 s = Semaphore(concurrent) reactor.suggestThreadPoolSize(concurrent) t=Thread( target=reactor.run, kwargs={'installSignalHandlers':True}) t.daemon=True t.start() agent = Agent(reactor) def processResponse(response,url): print response.code, url s.release() def processError(response,url): print "error", url s.release() def addTask(url): req = agent.request('HEAD', url) req.addCallback(processResponse, url) req.addErrback(processError, url) for url in open('urllist.txt'): addTask(url.strip()) s.acquire() while s._Semaphore__value!=concurrent: time.sleep(0.1) reactor.stop() And here is the error that it throws when installSignalHandlers is True: (Note: This is the expected behaviour! The question is why it doesn't work when installSignalHandlers is False.) Traceback (most recent call last): File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 396, in fireEvent DeferredList(beforeResults).addCallback(self._continueFiring) File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 224, in addCallback callbackKeywords=kw) File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 213, in addCallbacks self._runCallbacks() File "/usr/lib/python2.6/dist-packages/twisted/internet/defer.py", line 371, in _runCallbacks self.result = callback(self.result, *args, **kw) --- <exception caught here> --- File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 409, in _continueFiring callable(*args, **kwargs) File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 1165, in _reallyStartRunning self._handleSignals() File "/usr/lib/python2.6/dist-packages/twisted/internet/base.py", line 1105, in _handleSignals signal.signal(signal.SIGINT, self.sigInt) exceptions.ValueError: signal only works in main thread What am I doing wrong and what is the right way? I'm new to twisted.

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  • Simple menubar using Qt4

    - by Buzz
    Hi all i'm trying to make a simple GUI with QT 4.6. i made a separete class that represents the menu bar: MenuBar::MenuBar() { aboutAct = new QAction(tr("&About QT"), this); aboutAct->setStatusTip(tr("Show the application's About box")); connect(aboutAct, SIGNAL(triggered()), this, SLOT(about())); quitAct = new QAction(tr("&Quit"),this); quitAct->setStatusTip(tr("Exit to the program")); //connect(quitAct, SIGNAL(triggered()), &QApp, SLOT(quit())); menuFile = new QMenu("File"); menuFile->addAction(quitAct); menuLinks = new QMenu("Links"); menuAbout = new QMenu("Info"); menuAbout->addAction(aboutAct); addMenu(menuFile); addMenu(menuLinks); addMenu(menuAbout); } i can't connect the signal of the quitAct with the quit slot of the main application probably because it is not visible from the MenuBar class.. //connect(quitAct, SIGNAL(triggered()), &QApp, SLOT(quit())); how can i do it?

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  • UIImage imageNamed not autoreleasing correctly

    - by MrHen
    For some reason, the retain/release behavior in the following code has me completely baffled. selectedImage = [UIImage imageNamed:@"icon_72.png"]; [selectedImage release]; This should break but does not. Why? I thought imageNamed autoreleased itself which means the release here is redundant and should break when the autorelease occurs. Here are snippets relevant to selectedImage from the .h and .m files: @property (nonatomic, readonly) UIImage *selectedImage; @synthesize delegate, selectedImage, spacerBottom, currentIndex; Other notes, this does break: selectedImage = [UIImage imageNamed:@"icon_72.png"]; [selectedImage release]; [selectedImage release]; //objc[55541]: FREED(id): message release sent to freed object=0x59245b0 //Program received signal: “EXC_BAD_INSTRUCTION”. As does this: selectedImage = [UIImage imageNamed:@"icon_72.png"]; [selectedImage release]; [selectedImage autorelease]; //objc[55403]: FREED(id): message autorelease sent to freed object=0x59b54c0 //Program received signal: “EXC_BAD_INSTRUCTION”. And so does the following: selectedImage = [UIImage imageNamed:@"icon_72.png"]; [selectedImage autorelease]; [selectedImage release]; //objc[55264]: FREED(id): message release sent to freed object=0x592c9a0 //Program received signal: “EXC_BAD_INSTRUCTION”. And so does this: selectedImage = [UIImage imageNamed:@"icon_72.png"]; [selectedImage autorelease]; [selectedImage autorelease]; //objc[55635]: FREED(id): message release sent to freed object=0x5b305d0 //Program received signal: “EXC_BAD_INSTRUCTION”.

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  • verilog / systemverilog -- What is the behavior of blocking statements across two always blocks?

    - by miles.sherman
    I am wondering about the behavior of the below code. There are two always blocks, one is combinational to calculate the next_state signal, the other is sequential which will perform some logic and determine whether or not to shutdown the system. It does this by setting the shutdown_now signal high and then calling state <= next_state. My question is if the conditions become true that the shutdown_now signal is set (during clock cycle n) in a blocking manner before the state <= next_state line, will the state during clock cycle n+1 be SHUTDOWN or RUNNING? In other words, does the shutdown_now = 1'b1 line block across both state machines since the state signal is dependent on it through the next_state determination? enum {IDLE, RUNNING, SHUTDOWN} state, next_state; logic shutdown_now; // State machine (combinational) always_comb begin case (state) IDLE: next_state <= RUNNING; RUNNING: next_state <= shutdown ? SHUTDOWN : RUNNING; SHUTDOWN: next_state <= SHUTDOWN; default: next_state <= SHUTDOWN; endcase end // Sequential Behavior always_ff @ (posedge clk) begin // Some code here if (/*some condition) begin shutdown_now = 1'b0; end else begin shutdown_now = 1'b1; end state <= next_state; end

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  • Lightweight alternative to Manual/AutoResetEvent in C#

    - by sweetlilmre
    Hi, I have written what I hope is a lightweight alternative to using the ManualResetEvent and AutoResetEvent classes in C#/.NET. The reasoning behind this was to have Event like functionality without the weight of using a kernel locking object. Although the code seems to work well in both testing and production, getting this kind of thing right for all possibilities can be a fraught undertaking and I would humbly request any constructive comments and or criticism from the StackOverflow crowd on this. Hopefully (after review) this will be useful to others. Usage should be similar to the Manual/AutoResetEvent classes with Notify() used for Set(). Here goes: using System; using System.Threading; public class Signal { private readonly object _lock = new object(); private readonly bool _autoResetSignal; private bool _notified; public Signal() : this(false, false) { } public Signal(bool initialState, bool autoReset) { _autoResetSignal = autoReset; _notified = initialState; } public virtual void Notify() { lock (_lock) { // first time? if (!_notified) { // set the flag _notified = true; // unblock a thread which is waiting on this signal Monitor.Pulse(_lock); } } } public void Wait() { Wait(Timeout.Infinite); } public virtual bool Wait(int milliseconds) { lock (_lock) { bool ret = true; // this check needs to be inside the lock otherwise you can get nailed // with a race condition where the notify thread sets the flag AFTER // the waiting thread has checked it and acquires the lock and does the // pulse before the Monitor.Wait below - when this happens the caller // will wait forever as he "just missed" the only pulse which is ever // going to happen if (!_notified) { ret = Monitor.Wait(_lock, milliseconds); } if (_autoResetSignal) { _notified = false; } return (ret); } } }

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  • How to delete a QProcess instance correctly?

    - by Kopfschmerzen
    Hi everyone! I have a class looking like this: class FakeRunner : public QObject { Q_OBJECT private: QProcess* proc; public: FakeRunner(); int run() { if (proc) return -1; proc = new QProcess(); QStringList args; QString programName = "fake.exe"; connect(comp, SIGNAL(started()), this, SLOT(procStarted())); connect(comp, SIGNAL(error(QProcess::ProcessError)), this, SLOT(procError(QProcess::ProcessError))); connect(comp, SIGNAL(finished(int, QProcess::ExitStatus)), this, SLOT(procFinished(int, QProcess::ExitStatus))); proc->start(programName, args); return 0; }; private slots: void procStarted() {}; void procFinished(int, QProcess::ExitStatus) {}; void procError(QProcess::ProcessError); } Since "fake.exe" does not exist on my system, proc emits the error() signal. If I handle it like following, my program crashes: void FakeRunner::procError(QProcess::ProcessError rc) { delete proc; proc = 0; } It works well, though, if I don't delete the pointer. So, the question is how (and when) should I delete the pointer to QProcess? I believe I have to delete it to avoid a memory leak. FakeRunner::run() can be invoked many times, so the leak, if there is one, will grow. Thanks!

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  • Can I use POSIX signals in my Perl program to create event-driven programming?

    - by Shiftbit
    Is there any POSIX signals that I could utilize in my Perl program to create event-driven programming? Currently, I have multi-process program that is able to cross communicate but my parent thread is only able to listen to listen at one child at a time. foreach (@proc) { sysread(${$_}{'read'}, my $line, 100); #problem here chomp($line); print "Parent hears: $line\n"; } The problem is that the parent sits in a continual wait state until it receives it a signal from the first child before it can continue on. I am relying on 'pipe' for my intercommunication. My current solution is very similar to: http://stackoverflow.com/questions/2558098/how-can-i-use-pipe-to-facilitate-interprocess-communication-in-perl If possible I would like to rely on a $SIG{...} event or any non-CPAN solution. Update: As Jonathan Leffler mentioned, kill can be used to send a signal: kill USR1 = $$; # send myself a SIGUSR1 My solution will be to send a USR1 signal to my child process. This event tells the parent to listen to the particular child. child: kill USR1 => $parentPID if($customEvent); syswrite($parentPipe, $msg, $buffer); #select $parentPipe; print $parentPipe $msg; parent: $SIG{USR1} = { #get child pid? sysread($array[$pid]{'childPipe'}, $msg, $buffer); }; But how do I get my the source/child pid that signaled the parent? Have the child Identify itself in its message. What happens if two children signal USR1 at the same time?

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  • QLocalSocket and QLocalServer in browser plugins

    - by kambamsu
    Hi, I have a simple doubt. Does the ipc mechanism in qt work when we use it for developing browser plugins? The reason i ask this is that I can easily get the QLocalSocket and QLocalServer communication to work in a qt application, but when i write a similar piece of code in a browser plugin dll i see that the server does not accept a new connection at all. This is what i do in the server: server = new QLocalServer(this); if( !server->listen("myServer")) { writeFile("Listen failed"); } connect(server, SIGNAL(newConnection()), this, SLOT(handleConn()),Qt::QueuedConnection); and this is what i do in the client: client = new QLocalSocket(this); client->abort(); QObject::connect(client,SIGNAL(connected()),this,SLOT(connClient()),Qt::QueuedConnection); client->connectToServer("myServer"); after i call connectToServer, my client emits the connected() signal and the connClient() slot is called. But, on the server side, there is no signal emitted. It doesn't seem to be receiving any connection at all. Any help would be appreciated. Thanks

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  • How would i down-sample a .wav file then reconstruct it using nyquist? - in MATLAB

    - by Andrew
    This is all done in MATLAB 2010 My objective is to show the results of: undersampling, nyquist rate/ oversampling First i need to downsample the .wav file to get an incomplete/ or impartial data stream that i can then reconstuct. Heres the flow chart of what im going to be doing So the flow is analog signal - sampling analog filter - ADC - resample down - resample up - DAC - reconstruction analog filter what needs to be achieved: F= Frequency F(Hz=1/s) E.x. 100Hz = 1000 (Cyc/sec) F(s)= 1/(2f) Example problem: 1000 hz = Highest frequency 1/2(1000hz) = 1/2000 = 5x10(-3) sec/cyc or a sampling rate of 5ms This is my first signal processing project using matlab. what i have so far. % Fs = frequency sampled (44100hz or the sampling frequency of a cd) [test,fs]=wavread('test.wav'); % loads the .wav file left=test(:,1); % Plot of the .wav signal time vs. strength time=(1/44100)*length(left); t=linspace(0,time,length(left)); plot(t,left) xlabel('time (sec)'); ylabel('relative signal strength') **%this is were i would need to sample it at the different frequecys (both above and below and at) nyquist frequency.*I think.*** soundsc(left,fs) % shows the resaultant audio file , which is the same as original ( only at or above nyquist frequency however) Can anyone tell me how to make it better, and how to do the sampling at verious frequencies?

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  • Matlab fft function

    - by CTZStef
    The code below is from the Matlab 2011a help about fft function. I think there is a problem here : why do they multiply t(1:50) by Fs, and then say it's time in millisecond ? Certainly, it happens to be true in this very particular case, but change the value of Fs to, say, 2000, and it won't work anymore, obviously because of this factor of 2. Right ? Quite misleading, isn't it ? What do I miss ? Fs = 1000; % Sampling frequency T = 1/Fs; % Sample time L = 1000; % Length of signal t = (0:L-1)*T; % Time vector % Sum of a 50 Hz sinusoid and a 120 Hz sinusoid x = 0.7*sin(2*pi*50*t) + sin(2*pi*120*t); y = x + 2*randn(size(t)); % Sinusoids plus noise plot(Fs*t(1:50),y(1:50)) title('Signal Corrupted with Zero-Mean Random Noise') xlabel('time (milliseconds)') Clearer with this : fs = 2000; % Sampling frequency T = 1 / fs; % Sample time L = 1000; % Length of signal t2 = (0:L-1)*T; % Time vector f = 50; % signal frequency s2 = sin(2*pi*f*t2); figure, plot(fs*t2(1:50),s2(1:50)); % NOT good figure, plot(t2(1:50),s2(1:50)); % good

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  • what is the relation between SIGTSTP and SIGCHLD

    - by Rawhi
    I have tow handlers for each one of them (SIGTSTP, SIGCHLD), the thing is that when I pause a process using SIGTSTP the handler function of SIGCHLD run too. what should I do to prevent this . void ExeExternal(char *args[MAX_ARG], char* cmdString, LIST_ELEMENT** pList, int *Susp_Bg_Pid, int *susp) { int pID, status, w; switch (pID = fork()) { case -1: perror("smash error: >"); break; case 0: // Child Process setpgrp(); execv(args[0], args); execvp(args[0], args); perror("error"); exit(EXIT_FAILURE); break; default: if (cmdString[strlen(cmdString) - 1] != '&') { *Susp_Bg_Pid = pID; *susp = 1; while(*susp); } else { InsertElem(pList, args[0], getpid(), pID, 0); } break; } } signal handlers : void signalHandler(int signal) { int pid, cstatus; if (signal == SIGCHLD) { susp = 0; pid = waitpid(-1, &cstatus, WNOHANG); printf("[[child %d terminated]]\n", pid); DelPID(&JobsList, pid); } } void ctrlZsignal(int signal){ kill(Susp_Bg_Pid, SIGTSTP); susp = 0; printf("\nchild %d suspended\n", Susp_Bg_Pid); } Susp_Bg_Pid used to save the paused process id. susp indicates the state of the "smash" the parent process if it is suspended or not .

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  • Python easy_install confused on Mac OS X

    - by slf
    environment info: $ echo $PATH /opt/local/bin:/opt/local/sbin:/sw/bin:/sw/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin:/usr/X11R6/bin:/opt/local/bin:/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:~/.utility_scripts $ which easy_install /usr/bin/easy_install specifically, let's try the simplejson module (I know it's the same thing as import json in 2.6, but that isn't the point) $ sudo easy_install simplejson Searching for simplejson Reading http://pypi.python.org/simple/simplejson/ Reading http://undefined.org/python/#simplejson Best match: simplejson 2.1.0 Downloading http://pypi.python.org/packages/source/s/simplejson/simplejson-2.1.0.tar.gz#md5=3ea565fd1216462162c6929b264cf365 Processing simplejson-2.1.0.tar.gz Running simplejson-2.1.0/setup.py -q bdist_egg --dist-dir /tmp/easy_install-Ojv_yS/simplejson-2.1.0/egg-dist-tmp-AypFWa The required version of setuptools (>=0.6c11) is not available, and can't be installed while this script is running. Please install a more recent version first, using 'easy_install -U setuptools'. (Currently using setuptools 0.6c9 (/System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python)) error: Setup script exited with 2 ok, so I'll update setuptools... $ sudo easy_install -U setuptools Searching for setuptools Reading http://pypi.python.org/simple/setuptools/ Best match: setuptools 0.6c11 Processing setuptools-0.6c11-py2.6.egg setuptools 0.6c11 is already the active version in easy-install.pth Installing easy_install script to /usr/local/bin Installing easy_install-2.6 script to /usr/local/bin Using /Library/Python/2.6/site-packages/setuptools-0.6c11-py2.6.egg Processing dependencies for setuptools Finished processing dependencies for setuptools I'm not going to speculate, but this could have been caused by any number of environment changes like the Leopard - Snow Leopard upgrade, MacPorts or Fink updates, or multiple Google App Engine updates.

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  • Postfix installation error on Ubuntu

    - by kgpdeveloper
    How do I fix this error on Ubuntu 10.04 ? Reading package lists... Done Building dependency tree Reading state information... Done postfix is already the newest version. The following packages were automatically installed and are no longer required: libaprutil1-dbd-sqlite3 libcap2 apache2.2-bin libapr1 libaprutil1-ldap libaprutil1 php5-common Use 'apt-get autoremove' to remove them. 0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded. 1 not fully installed or removed. After this operation, 0B of additional disk space will be used. Setting up postfix (2.7.0-1) ... Postfix configuration was not changed. If you need to make changes, edit /etc/postfix/main.cf (and others) as needed. To view Postfix configuration values, see postconf(1). After modifying main.cf, be sure to run '/etc/init.d/postfix reload'. Running newaliases newaliases: warning: valid_hostname: numeric hostname: 202002 newaliases: fatal: file /etc/postfix/main.cf: parameter myhostname: bad parameter value: 202002 dpkg: error processing postfix (--configure): subprocess installed post-installation script returned error exit status 75 Processing triggers for libc-bin ... ldconfig deferred processing now taking place Errors were encountered while processing: postfix E: Sub-process /usr/bin/dpkg returned an error code (1) Even if I reboot, the same error shows up. Thanks for the help..

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