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• What is the recommended way to empty a SSD?

  - by Lekensteyn

  I've just received my new SSD since the old one died. This Intel 320 SSD supports TRIM. For testing purposes, my dealer put malware, err, Windows on it. I want to get rid of it and install Kubuntu on it. It does not have to be a "secure wipe", I just need the empty the disk in the mosy healthy way. I believe that dd if=/dev/zero of=/dev/sda just fills the blocks with zeroes and thereby taking another write (correct me if I'm wrong). I've seen the answer How to enable TRIM, but it looks like it's suited for clearing empty blocks, not wiping the disk. hdparm seems to be the program to do it, but I'm not sure if it clears the disk OR cleans empty blocks. From its manual page: --trim-sector-ranges For Solid State Drives (SSDs). EXCEPTIONALLY DANGEROUS. DO NOT USE THIS OPTION!! Tells the drive firmware to discard unneeded data sectors, destroying any data that may have been present within them. This makes those sectors available for immediate use by the firmware's garbage collection mechanism, to improve scheduling for wear-leveling of the flash media. This option expects one or more sector range pairs immediately after the option: an LBA starting address, a colon, and a sector count, with no intervening spaces. EXCEPTIONALLY DANGEROUS. DO NOT USE THIS OPTION!! E.g. hdparm --trim-sector-ranges 1000:4 7894:16 /dev/sdz How can I make all blocks appear as empty using TRIM?

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• Tail-recursive implementation of take-while

  - by Giorgio

  I am trying to write a tail-recursive implementation of the function take-while in Scheme (but this exercise can be done in another language as well). My first attempt was (define (take-while p xs) (if (or (null? xs) (not (p (car xs)))) '() (cons (car xs) (take-while p (cdr xs))))) which works correctly but is not tail-recursive. My next attempt was (define (take-while-tr p xs) (let loop ((acc '()) (ys xs)) (if (or (null? ys) (not (p (car ys)))) (reverse acc) (loop (cons (car ys) acc) (cdr ys))))) which is tail recursive but needs a call to reverse as a last step in order to return the result list in the proper order. I cannot come up with a solution that is tail-recursive, does not use reverse, only uses lists as data structure (using a functional data structure like a Haskell's sequence which allows to append elements is not an option), has complexity linear in the size of the prefix, or at least does not have quadratic complexity (thanks to delnan for pointing this out). Is there an alternative solution satisfying all the properties above? My intuition tells me that it is impossible to accumulate the prefix of a list in a tail-recursive fashion while maintaining the original order between the elements (i.e. without the need of using reverse to adjust the result) but I am not able to prove this. Note The solution using reverse satisfies conditions 1, 3, 4.

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• Internet slow on one router only [the problem only in Ubuntu] [on hold]

  - by mrSuperEvening

  Internet works perfectly on every other router, but browsing sucks at home (slow browsing and slow loading times). I changed DNS servers to 8.8.0.0, still doesn't help. And funnily, download speed is extremely high on this network (meaning torrents for example), but using browsers and loading websites is extremely slow (only on this network). Do I need to change something in router settings or what can I try? By the way, I use wired connection to router. EDIT: There's no problems when using Windows. EDIT: ifconfig: eth0 Link encap:Ethernet HWaddr f2:4d:a0:c0:3f:4c inet addr:192.168.11.8 Bcast:192.168.11.255 Mask:255.255.255.0 inet6 addr: fe80::f24d:a2ff:fec6:3f4c/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:206798 errors:0 dropped:0 overruns:0 frame:0 TX packets:219570 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:76680734 (76.6 MB) TX bytes:21738160 (21.7 MB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:160 errors:0 dropped:0 overruns:0 frame:0 TX packets:160 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:11094 (11.0 KB) TX bytes:11094 (11.0 KB)` ping -c 2 4.2.2.2 PING 4.2.2.2 (4.2.2.2) 56(84) bytes of data. --- 4.2.2.2 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1007ms ping -c 2 google.com PING google.com (213.159.32.147) 56(84) bytes of data. 64 bytes from lan-213-159-32-147.kns.skynet.lv (213.159.32.147): icmp_seq=1 ttl=61 time=0.936 ms 64 bytes from lan-213-159-32-147.kns.skynet.lv (213.159.32.147): icmp_seq=2 ttl=61 time=0.937 ms --- google.com ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 1001ms rtt min/avg/max/mdev = 0.936/0.936/0.937/0.030 ms

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• Thoughts on exception handling.

  - by AndyScott

  Was working on a windows form app (something I haven't done in a while), adding threading and logging so that it would work a little more smoothly and have a record of who did what.  I was just about at the point where I was going to check it into source control when I noticed that the Output window was showing "A first chance exception of type 'System.InvalidCastException' occurred in mscorlib.dll", so I googled it.  In reading some threads about the error, I came across the following comment and it got me thinking: "In addition, while they should be avoided if possible, exceptions are a quite legitimate part of program execution. It's their going unhandled that is a real issue, because that means crashy, crashy." How do you normally use exception handling?  I feel that exceptions are intended to handle errors in code (in my experience generally related to bad data making its way into the system).  Now don't get me wrong, I understand that exceptions happen and should be dealt with, but I feel that they are a "last resort" to keep a program from crashing, but should never be a way to pass data or continue logical processing that could be handled in standard code flow. I mention this, because I have seen it done. What do you think?

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• Complex string matching with fuzzywuzzy

  - by That1Guy

  I'm attempting to write a process that matches obscure strings to a single 'master string' for further processing. I have a lot of data that looks something like this: Basketball Basket Ball Football BasketBallR BBall BBall - r FootB ...and so on. These need to be mapped to a master record like so: Basketball = Basket Ball, BBall Basketball - R = BasketBallR, BBall - r I also have instances of data resembling this format: Football -r FootBall - r-g/H,Q,HH These situations need to be separated into different categories before being mapped. For example FootBall - r-g/H,Q,HH should be: Football - r Football - g Football - H Football - Q Football - HH At this point, it still needs to be mapped to a master record... I've tried several different combinations of fuzzywuzzy matching methods, Levenshtein Distance measurements, regex, etc. and can't seem to find a reliable method to logically associate different naming styles of a single item with a master name. I'm throwing my hands up in desperation. Are there any existing python resources than can help sort out my problem? Are there other options? Can anybody point out an obvious option that I might have overlooked? Basically, any suggestion, solution, resource or alternative method is greatly appreciated.

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• Good design for class with similar constructors

  - by RustyTheBoyRobot

  I was reading this question and thought that good points were made, but most of the solutions involved renaming one of the methods. I am refactoring some poorly written code and I've run into this situation: public class Entity { public Entity(String uniqueIdentifier, boolean isSerialNumber) { if (isSerialNumber) { this.serialNumber = uniqueIdentifier; //Lookup other data } else { this.primaryKey = uniqueIdentifier; // Lookup other data with different query } } } The obvious design flaw is that someone needed two different ways to create the object, but couldn't overload the constructor since both identifiers were of the same type (String). Thus they added a flag to differentiate. So, my question is this: when this situation arises, what are good designs for differentiating between these two ways of instantiating an object? My First Thoughts You could create two different static methods to create your object. The method names could be different. This is weak because static methods don't get inherited. You could create different objects to force the types to be different (i.e., make a PrimaryKey class and a SerialNumber class). I like this because it seems to be a better design, but it also is a pain to refactor if serialNumber is a String everywhere else.

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• Using ConcurrentQueue for thread-safe Performance Bookkeeping.

  - by Strenium

  Just a small tidbit that's sprung up today. I had to book-keep and emit diagnostics for the average thread performance in a highly-threaded code over a period of last X number of calls and no more. Need of the day: a thread-safe, self-managing stats container. Since .NET 4.0 introduced new thread-safe 'Collections.Concurrent' objects and I've been using them frequently - the one in particular seemed like a good fit for storing each threads' performance data - ConcurrentQueue. But I wanted to store only the most recent X# of calls and since the ConcurrentQueue currently does not support size constraint I had to come up with my own generic version which attempts to restrict usage to numeric types only: unfortunately there is no IArithmetic-like interface which constrains to only numeric types – so the constraints here here aren't as elegant as they could be. (Note the use of the Average() method, of course you can use others as well as make your own).   FIFO FixedSizedConcurrentQueue using System;using System.Collections.Concurrent;using System.Linq; namespace xxxxx.Data.Infrastructure{    [Serializable]    public class FixedSizedConcurrentQueue<T> where T : struct, IConvertible, IComparable<T>    {        private FixedSizedConcurrentQueue() { }         public FixedSizedConcurrentQueue(ConcurrentQueue<T> queue)        {            _queue = queue;        }         ConcurrentQueue<T> _queue = new ConcurrentQueue<T>();         public int Size { get { return _queue.Count; } }        public double Average { get { return _queue.Average(arg => Convert.ToInt32(arg)); } }         public int Limit { get; set; }        public void Enqueue(T obj)        {            _queue.Enqueue(obj);            lock (this)            {                T @out;                while (_queue.Count > Limit) _queue.TryDequeue(out @out);            }        }    } }   The usage case is straight-forward, in this case I’m using a FIFO queue of maximum size of 200 to store doubles to which I simply Enqueue() the calculated rates: Usage var RateQueue = new FixedSizedConcurrentQueue<double>(new ConcurrentQueue<double>()) { Limit = 200 }; /* greater size == longer history */   That’s about it. Happy coding!

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• Webcast: DB Enterprise User Security Integration with Oracle Directory Services

  - by B Shashikumar

  The typical enterprise has a large number of DBA (Database administrator) accounts that are locally managed, which is often very costly, problematic and error-prone. Databases are a crucial component of your enterprise IT infrastructure, housing sensitive corporate data and database user accounts and privileges. To ensure the integrity of your enterprise's data, it's imperative to have a well-managed identity management system. This begins with centralized management of user accounts and access rights. Enterprise User Security (EUS), an Oracle Database Enterprise Edition feature, combined with Oracle Identity Management, gives you the ability to centrally manage database users and their authorizations in one central place. The cost of user provisioning and password resets is dramatically reduced. This technology is a must for new application development and should be considered for existing applications as well. Join Oracle Advisors for a live webcast on Jul 11 at 8am Pacific Time where Oracle experts will briefly introduce EUS, followed by a detailed discussion about the various directory options that are supported, including integration with Microsoft Active Directory. We'll conclude how to avoid common pitfalls deploying EUS with directory services. To register for this event, click here  

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• How can I malloc an array of struct to do the following using file operation?

  - by RHN

  How can malloc an array of struct to do the following using file operation? the file is .txt input in the file is like: 10 22 3.3 33 4.4 I want to read the first line from the file and then I want to malloc an array of input structures equal to the number of lines to be read in from the file. Then I want to read in the data from the file and into the array of structures malloc. Later on I want to store the size of the array into the input variable size. return an array.After this I want to create another function that print out the data in the input variable in the same form like input file and suppose a function call clean_data will free the malloc memory at the end. I have tried somthing like: struct input { int a; float b,c; } struct input* readData(char *filename,int *size); int main() { return 0; } struct input* readData(char *filename,int *size) { char filename[] = "input.txt"; FILE *fp = fopen(filename, "r"); int num; while(!feof(fp)) { fscanf(fp,"%f", &num); struct input *arr = (struct input*)malloc(sizeof(struct input)); } }

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• Working with the ADF DVT Map Component

  - by Shay Shmeltzer

  The map component provided by the ADF Faces DVT set of components is one that we are always ending up using in key demos - simply because it is so nice looking, but also because it is quite simple to use. So in case you need to show some geographical data, or if you just want to impress your manager, here is a little video that shows you how to create two types of maps. The first one is a color themed map - where you show different states with different colors based on the value of some data point there. The other is a point theme - basically showing specific locations on the map. For both cases I'm using the Oracle provided mapviewer instance at http://elocation.oracle.com/mapviewer. You can find more information about using the map component in the Web User Interface Developer's Guide here and in the tag doc and components demo. For the first map the query I'm using (on the HR demo schema in the Oracle DB) is: SELECT     COUNT(EMPLOYEES.EMPLOYEE_ID) , Department_name , STATE_PROVINCE FROM     EMPLOYEES,     DEPARTMENTS,     LOCATIONS WHERE employees.department_id=departments.department_idand Departments.location_id=locations.location_idGROUP BY Department_name,    LOCATIONS.STATE_PROVINCE

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• What are some ways to separate game logic from animations and the draw loop?

  - by TMV

  I have only previously made flash games, using MovieClips and such to separate out my animations from my game logic. Now I am getting into trying my hand at making a game for Android, but the game programming theory around separating these things still confuses me. I come from a background of developing non game web applications so I am versed in more MVC like patterns and am stuck in that mindset as I approach game programming. I want to do things like abstract my game by having, for example, a game board class that contains the data for a grid of tiles with instances of a tile class that each contain properties. I can give my draw loop access to this and have it draw the game board based on the properties of each tile on the game board, but I don't understand where exactly animation should go. As far as I can tell, animation sort of sits between the abstracted game logic (model) and the draw loop (view). With my MVC mindset, it's frustrating trying to decide where animation is actually supposed to go. It would have quite a bit of data associated with it like a model, but seemingly needs to be very closely coupled with the draw loop in order to have things like frame independent animation. How can I break out of this mindset and start thinking about patterns that make more sense for games?

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• Implementing my Entity System. Questions about some problems I have found.

  - by Notbad

  Hi!, Well during this week I have deciding about implementation of my entity system. It is a big topic so it has been difficult to take one option from the whole. This has been my decision: 1) I don't have an entity class it is just an id. 2) I have systems that contain a list of components (the list is homegenous, I mean, RenderSystem will just have RenderComponents). 3) Compones will be just data. 4) There would be some kind of "entity prototypes" in a manager or something from we will create entity instances.Ideally they will define the type of components it has and initialization data. 5) Prototype code to create an entity (this is from the top of my head): int id=World::getInstance()->createEntity("entity template"); 6) This will notify all systems that a new entity has been created, and if the entity needs a component that the system handles it will add it to the entity. Ok, this are the ideas. Let's see if some can help with the problems: 1) The main problem is this templates that are sent to the systems in creation process to populate the entity with needed components. What would you use, an OR(ed) int?, a list of strings?. 2) How to do initialization for components when the entity has been created? How to store this in the template? I have thought about having a function in the template that is virtual and after entity is created an populated, gets the components and sets initialization values. 3) Don't you think this is a lot of work for just an entity creation?. Sorry for the long post, I have tried to expose my ideas and finding in order other could have a start beside exposing my problems. Thanks in advance, Notbad.

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• How do I develop database-utilizing application in an agile/test-driven-development way?

  - by user39019

  I want to add databases (traditional client/server RDBMS's like Mysql/Postgresql as opposed to NoSQL, or embedded databases) to my toolbox as a developer. I've been using SQLite for simpler projects with only 1 client, but now I want to do more complicated things (ie, db-backed web development). I usually like following agile and/or test-driven-development principles. I generally code in Perl or Python. Questions: How do I test my code such that each run of the test suite starts with a 'pristine' state? Do I run a separate instance of the database server every test? Do I use a temporary database? How do I design my tables/schema so that it is flexible with respect to changing requirements? Do I start with an ORM for my language? Or do I stick to manually coding SQL? One thing I don't find appealing is having to change more than one thing (say, the CREATE TABLE statement and associated crud statements) for one change, b/c that's error prone. On the other hand, I expect ORM's to be a low slower and harder to debug than raw SQL. What is the general strategy for migrating data between one version of the program and a newer one? Do I carefully write ALTER TABLE statements between each version, or do I dump the data and import fresh in the new version?

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• How can I tell if I am overusing multi-threading?

  - by exhuma

  NOTE: This is a complete re-write of the question. The text before was way too lengthy and did not get to the point! If you're interested in the original question, you can look it up in the edit history. I currently feel like I am over-using multi-threading. I have 3 types of data, A, B and C. Each A can be converted to multiple Bs and each B can be converted to multiple Cs. I am only interested in treating Cs. I could write this fairly easily with a couple of conversion functions. But I caught myself implementing it with threads, three queues (queue_a, queue_b and queue_c). There are two threads doing the different conversions, and one worker: ConverterA reads from queue_a and writes to queue_b ConverterB reads from queue_b and writes to queue_c Worker handles each element from queue_c The conversions are fairly mundane, and I don't know if this model is too convoluted. But it seems extremely robust to me. Each "converter" can start working even before data has arrived on the queues, and at any time in the code I can just "submit" new As or Bs and it will trigger the conversion pipeline which in turn will trigger a job by the worker thread. Even the resulting code looks simpler. But I still am unsure if I am abusing threads for something simple.

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• Rendering multiple squares fast?

  - by Sam

  so I'm doing my first steps with openGL development on android and I'm kinda stuck at some serious performance issues... What I'm trying to do is render a whole grid of single colored squares on to the screen and I'm getting framerates of ~7FPS. The squares are 9px in size right now with one pixel border in between, so I get a few thousand of them. I have a class "Square" and the Renderer iterates over all Squares every frame and calls the draw() method of each (just the iteration is fast enough, with no openGL code the whole thing runs smootlhy at 60FPS). Right now the draw() method looks like this: // Prepare the square coordinate data GLES20.glVertexAttribPointer(mPositionHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false, vertexStride, vertexBuffer); // Set color for drawing the square GLES20.glUniform4fv(mColorHandle, 1, color, 0); // Draw the square GLES20.glDrawElements(GLES20.GL_TRIANGLES, drawOrder.length, GLES20.GL_UNSIGNED_SHORT, drawListBuffer); So its actually only 3 openGL calls. Everything else (loading shaders, filling buffers, getting appropriate handles, etc.) is done in the Constructor and things like the Program and the handles are also static attributes. What am I missing here, why is it rendering so slow? I've also tried loading the buffer data into VBOs, but this is actually slower... Maybe I did something wrong though. Any help greatly appreciated! :)

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• failbit is being set and I can't figure out why

  - by felipedrl

  I'm writing a MIDI file loader. Everything is going fine until at some track I get a failbit exception while trying to read from file. I can't figure out why, I've checked the file size and it's ok too. Upon checking "errno" and it returns "0". Any ideas? Thanks. The snippet follows: file.read(reinterpret_cast<char*>(&mHeader.id), sizeof(MidiHeader)); mTracks = new MidiTrack[mHeader.nTracks]; for (uint i = 0; i < mHeader.nTracks; ++i) { // this read fails on 6th i. I've checked hexadecimal file and it's // ok so far. file.read(reinterpret_cast<char*>(&mTracks[i].id), sizeof(uint)); if (file.fail()) { std::cerr << errno << std::endl; massert(false); } massert(mTracks[i].id == 0x6B72544D); file.read(reinterpret_cast<char*>(&mTracks[i].size), sizeof(uint)); mTracks[i].size = swapBytes(mTracks[i].size); mTracks[i].data = new char[mTracks[i].size]; file.read(mTracks[i].data, mTracks[i].size * sizeof(char)); totalBytesRead += 8 + mTracks[i].size; massert(totalBytesRead <= fileSize); }

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• Dim (NEARLY blank) laptop screen, secondary screen works - why?

  - by LIttle Ancient Forest Kami

  My laptop screen is (almost) black while my secondary screen is fine. I believe it to be backlight / brightness related. Problem description it starts when I start the laptop system loads and works fine, just screen has problems I can see the screen though very faintly / dimly - it's hard to see anything which ain't very white e.g. starting screen has big Thinkpad logo in white, large font - I can see it, though very dimly second screen works very well Official backligtht debugging: using acpi setting as prescribed there for Thinkpads didn't help I can see an entry in /sys/class/backlight/ and it changes when I press hotkeys for brightness (current backlight power for instance goes up or down) acpi-off didn't helpm neither did acpi_backlight=vendor Hardware data Laptop is Thinkpad Edge with glossy screen. 4 processors, 2 cores, exemplary CPU data from cat /proc/cpuinfo reports Genuine Intel i5 (M 480 @ 2.67GHz). OS is Ubuntu Lucid, 10.04 LTS, 64-bit, with Linux generic kernel (2.6.32-44) and GNOME 2.32.2 (though I doubt there lies the problem). $ lspci | grep VGA 01:00.0 VGA compatible controller: ATI Technologies Inc M92 [Mobility Radeon HD 4500 Series] $ lshw -C display *-display description: VGA compatible controller product: M92 [Mobility Radeon HD 4500 Series] vendor: ATI Technologies Inc physical id: 0 bus info: pci@0000:01:00.0 version: 00 width: 32 bits clock: 33MHz capabilities: pm pciexpress msi bus_master cap_list rom configuration: driver=radeon latency=0 resources: irq:33 memory:c0000000-dfffffff(prefetchable) ioport:2000(size=256) memory:f0300000-f030ffff memory:f0320000-f033ffff(prefetchable) Driver I was NOT running any proprietary drivers, just checked with "Hardware drivers". There is one for ATI that is suggested there, though I didn't need it so far. UPDATE: changing the driver to proprietary one (ATI/AMD FGLRX) didn't help. Tried and failed Resetting / running on power or battery / charging / getting rid of static electricity / warming up *doesn't help* This is NOT a blank-screen problem, at least it isn't following official Ubuntu black-screen diagnostics - I can see my screen, though barely. What I will try next: - check last updates I've made - IIRC I am running on nomodeset already, but will verify this Any ideas how to proceed best? What is most probable cause?

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• What problem does double or triple buffering solve in modern games?

  - by krokvskrok

  I want to check if my understanding of the causes for using double (or triple) buffering is correct: A monitor with 60Hz refresh's the monitor-display 60 times per second. If the monitor refresh the monitor-display, he updates pixel for pixel and line for line. The monitor requests the color values for the pixels from the video memory. If I run now a game, then this game is constantly manipulating this video memory. If this game don't use a buffer strategy (double buffering etc.) then the following problem can happen: The monitor is now refreshing his monitor-display. At this moment the monitor had refreshed the first half monitor-display already. At the same time, the game had manipulated the video memory with new data. Now the monitor accesses for the second half monitor-display this new manipulated data from the video memory. The problems can be tearing or flickering. Is my understanding of cases of using buffer strategy correct? Are there other reasons?

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• Pipe an infinite stream to internal loop?

  - by Sh3ljohn

  I've seen a lot of things about redirecting stdout to a TCP socket, but no real example of how to do it in practice, specifically when the output stream generated by the first "command" never ends. To talk about something concrete, let's take programs like servers that typically output their log endlessly to stdout (well, as long as they run). If you redirect the output to a log file on the disk, then this file is always open (therefore not readable by others?) and grows infinitely, which eventually is going to cause problems. This might be a nood question, but I don't know what it does or how to do it so. How to redirect the output of a command to the internal loop? I want to make sure that data is sent EVERY time something is written to stdout, and that the pipe won't wait for the command to end (never happens ideally!). Is that right? If 2 is true, is there a buffer system to send chunks of data once it reaches a certain size only? Could you give me concrete command line examples to do the above? Thanks in advance

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• Javascript Event in Innerhtml Resulting from PHP Server Script

  - by user144527

  I'm (very slowly) making a website, and I'm creating a search engine for the database, which is essential to organize the dependencies during data entry. Anyway, what I would like is to type a few keywords into a box, have a menu pop up with various search results, and have the box fill with the ID number of the selected entry when it's clicked. Currently, I have a document called search.php which fills a div called search-output using xmlhttp.open() and the innerhtml property. Everything is working perfectly except for filling the original search box with the ID number when clicking. My first attempt was to add an onclick event to each entry in the output from search.php. Unfortunately, I found that javascript inserted into innerhtml is not run for security reasons. I've been Googling for hours but haven't been able to find a solution. How can I get the original search text box to fill with the correct ID when I click it? Is what I'm doing a good setup for the results I desire, or is there a better way to integrate search features into data entry?

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• What relational database system should I learn? [closed]

  - by acidzombie24

  At the moment i know sqlite (my favorite), mysql (its ok, i get annoyed) and i do not want to learn ms/t sql (it only allows one nullable row if the column is unique). I am thinking about learning a new database system. My requirements for it is Must allow multiple connections at once (read and write) All or data i choose must be ACID compliant Performance should be good. I have a 17gb table in one project. It should perform well on read and transactional writes. With mysql it took hours to restore it and there were no foreign keys on that specific table. It only finished in a workday because i found a suggestion to adjust a setting which i think was key-buffer. And it still took hours Unique columns that allow more then one row to be null. I shouldn't have to say it but dammit MS. Allows one to make ongoing backups. Something like 'binary logs'. Some relatively small amounts of data i can grab and apply it to my local db to have it in sync with the one on the server. Table joins. I rather not write a bunch of queries to simulate a join What I would like but is not required Foreign keys. This may be a requirement later Open sourced Fair tool support. So i can measure queries, easily backup/restore, etc .NET and C (or C++) interface. (I seen one that uses raw tcp with JSON which was okish) Good subquery support. Once i was working with an older version of mysql (i believe <5.1 but it could have been 5.1) and i had to write many queries to do one query because it couldn't do subqueries. Or maybe it couldnt do it efficiently and died bc of memory limitations with a huge dataset. What db system should i learn?

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• So what is Active GridLink for RAC?

  - by Ruma Sanyal

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 I had referred to Active GridLink for RAC in my blog yesterday and since then got several questions on this topic. So I decided to re-visit Active GridLink. With the release of version 11g, Oracle WebLogic Server started to provide strong support for the Real Application Clusters (RAC) features in Oracle Database 11g, minimizing database access time while allowing transparent access to rich pooling management functions that maximizes both connection performance and availability. WebLogic is the only application server in the marketplace which has been fully integrated and certified with Oracle Database RAC 11g without losing any rich functionality. Active GridLink provides Fast Connection Failover (FCF), Runtime Connection Load-Balancing (RCLB), and RAC instance graceful shutdown. With the key foundation for providing deeper integration with Oracle RAC, this single data source implementation in Oracle WebLogic Server supports the full and unrestricted use of database services as the connection target for a data source. For more details and to understand how our customer NEC leverages this capability, read the whitepapers on this topic. Get in depth ‘how-to’ details from this youtube video from our resident expert, Frances Zhao.

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• Need help understanding Mocks and Stubs

  - by Theomax

  I'm new to use mocking frameworks and I have a few questions on the things that I am not clear on. I'm using Rhinomocks to generate mock objects in my unit tests. I understand that mocks can be created to verify interactions between methods and they record the interactions etc and stubs allow you to setup data and entities required by the test but you do not verify expectations on stubs. Looking at the recent unit tests I have created, I appear to be creating mocks literally for the purpose of stubbing and allowing for data to be setup. Is this a correct usage of mocks or is it incorrect if you're not actually calling verify on them? For example: user = MockRepository.GenerateMock<User>(); user.Stub(x => x.Id = Guid.NewGuid()); user.Stub(x => x.Name = "User1"); In the above code I generate a new user mock object, but I use a mock so I can stub the properties of the user because in some cases if the properties do not have a setter and I need to set them it seems the only way is to stub the property values. Is this a correct usage of stubbing and mocking? Also, I am not completely clear on what the difference between the following lines is: user.Stub(x => x.Id).Return(new Guid()); user.Stub(x => x.Id = Guid.NewGuid());

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• Logging Output of Azure Startup Tasks to the Event Log

  - by Your DisplayName here!

  This can come in handy when troubleshooting: using System; using System.Diagnostics; using System.Text;   namespace Thinktecture.Azure {     class Program     {         static EventLog _eventLog = new EventLog("Application", ".", "StartupTaskShell");         static StringBuilder _out = new StringBuilder(64);         static StringBuilder _err = new StringBuilder(64);           static int Main(string[] args)         {             if (args.Length != 1)             {                 Console.WriteLine("Invalid arguments: " + String.Join(", ", args));                 _eventLog.WriteEntry("Invalid arguments: " + String.Join(", ", args));                                 return -1;             }               var task = args[0];               ProcessStartInfo info = new ProcessStartInfo()             {                 FileName = task,                 WorkingDirectory = Environment.CurrentDirectory,                 UseShellExecute = false,                 ErrorDialog = false,                 CreateNoWindow = true,                 RedirectStandardOutput = true,                 RedirectStandardError = true             };               var process = new Process();             process.StartInfo = info;               process.OutputDataReceived += (s, e) =>                 {                     if (e.Data != null)                     {                         _out.AppendLine(e.Data);                     }                 };             process.ErrorDataReceived += (s, e) =>                 {                     if (e.Data != null)                     {                         _err.AppendLine(e.Data);                     }                 };               process.Start();             process.BeginOutputReadLine();             process.BeginErrorReadLine();             process.WaitForExit();               var outString = _out.ToString();             var errString = _err.ToString();               if (!string.IsNullOrWhiteSpace(outString))             {                 outString = String.Format("Standard Out for {0}\n\n{1}", task, outString);                 _eventLog.WriteEntry(outString, EventLogEntryType.Information);             }               if (!string.IsNullOrWhiteSpace(errString))             {                 errString = String.Format("Standard Err for {0}\n\n{1}", task, errString);                 _eventLog.WriteEntry(errString, EventLogEntryType.Error);             }               return 0;         }     } } You then wrap your startup tasks with the StartupTaskShell and you’ll be able to see stdout and stderr in the application event log.

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• Oracle HRMS API - Hire Into Job

  - by PRajkumar

  API - hr_employee_api.hire_into_job Example --   Consider a Contact for some employee already exist in Oracle System. Now that Contact has got Job, so his Person type should be converted to Employee from Contact (External)     Following API helps to create assignment for that Contact and helps to change his Person Type    DECLARE      -- Local Variables      -- ---------------------      lc_dt_ud_mode             VARCHAR2(100)  := NULL;      ln_person_id                 NUMBER               := 32981;      ln_object_number        NUMBER               := 1;      ld_effective_date            DATE                     := TO_DATE('28-JUN-2012');      lc_employee_number  VARCHAR2(100)  := 'CONTACT_TEST_01';        -- Out Variables for Find Date Track Mode API      -- ------------------------------------------------------------      lb_correction                          BOOLEAN;      lb_update                               BOOLEAN;      lb_update_override              BOOLEAN;      lb_update_change_insert   BOOLEAN;        -- Out Variables for Hire to Job API    -- -------------------------------------------    ld_effective_start_date           DATE;    ld_effective_end_date            DATE;    lb_assign_payroll_warning   BOOLEAN;    lb_orig_hire_warning              BOOLEAN;    ln_assignment_id                    NUMBER;   BEGIN    -- Find Date Track Mode    -- ----------------------------    dt_api.find_dt_upd_modes    (   -- Input data elements        -- ---------------------------        p_effective_date                 => TO_DATE('28-JUN-2012'),        p_base_table_name         => 'PER_ALL_PEOPLE_F',        p_base_key_column         => 'PERSON_ID',        p_base_key_value             => ln_person_id,        -- Output data elements        -- -----------------------------        p_correction                          => lb_correction,        p_update                               => lb_update,        p_update_override              => lb_update_override,        p_update_change_insert  => lb_update_change_insert    );         IF ( lb_update_override = TRUE OR lb_update_change_insert = TRUE )    THEN        -- UPDATE_OVERRIDE        -- -----------------------------        lc_dt_ud_mode := 'UPDATE_OVERRIDE';    END IF;       IF ( lb_correction = TRUE )    THEN        -- CORRECTION        -- --------------------        lc_dt_ud_mode := 'CORRECTION';    END IF;       IF ( lb_update = TRUE )    THEN        -- UPDATE        -- --------------        lc_dt_ud_mode := 'UPDATE';    END IF;      -- Hire into Job API    -- ------------------------    hr_employee_api.hire_into_job    (   -- Input Data Elements        -- -----------------------------        p_effective_date                     => ld_effective_date,        p_person_id                           => ln_person_id,        p_datetrack_update_mode  => lc_dt_ud_mode,        -- Output Data Elements        -- ----------------------------        p_object_version_number    => ln_object_number,        p_employee_number             => lc_employee_number,        p_assignment_id                   => ln_assignment_id,        p_effective_start_date           => ld_effective_start_date,        p_effective_end_date            => ld_effective_end_date,        p_assign_payroll_warning   => lb_assign_payroll_warning,        p_orig_hire_warning             => lb_orig_hire_warning    );    COMMIT; EXCEPTION         WHEN OTHERS THEN                        ROLLBACK;                        DBMS_OUTPUT.PUT_LINE(SQLERRM); END; / SHOW ERR;  

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