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• Apache2 + FCGI + PHP5 not creating sockets / pools

  - by CodyRo

  I have a pretty vanilla setup with Apache2, FastCGI setup as DSO and serving PHP through an external CGI script that sets the max children / serves the request to PHP. The issue is FastCGI doesn't appear to be creating the PHP sockets / pooling them so each request calls the php-cgi binary, then dies off .. effectively making the reason I want to use FastCGI moot. The only configuration directives I have are: AddHandler php5-fastcgi .php Action php5-fastcgi /cgi-bin/fcgi.cgi FastCgiIpcDir /usr/local/apache2/fastcgi The dyanmic/ directory is getting created as anticipated, but there are no sockets in there. Permissions are indeed correct. Any help would be greatly appreciated, thanks!

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• javascript: waiting for an iframe page to load before writing to it (but not from the page that's tr

  - by Bill Dawes

  Apologies if this has been answered elsewhere, but I haven't been able to find it referenced. (Probably because nobody else would want to do such a daft thing, I admit). So, I have a page with three iframes in it. An event on one triggers a javascript function which loads new pages into the other two iframes; ['topright'] and ['bottomright']. However, javascript in the page that is being loaded into iframe 'topright' then needs to send information to elements in the 'bottomright' iframe. window.frames['bottomright'].document.subform.ID_client = client; etc But this will only work if the page has fully loaded into the bottomright frame. So what would be the most efficient way for that code in the 'topright' iframe to check and ensure that that form element in the bottomright frame is actually available to write to, before it does write to it? Bearing in mind that the page load has NOT been triggered from the topright frame, so I can't simply use an onLoad function. (I know this probably sounds like a hideously tortuous route for getting data from one page to another, but that's another story. The client is always right, etc...:-))

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• sqlite3 'database is locked' won't go away with retries

  - by Azarias

  I have a sqlite3 database that is accessed by a few threads (3-4). I am aware of the general limitations of sqlite3 with regards to concurrency as stated http://www.sqlite.org/faq.html#q6 , but I am convinced that is not the problem. All of the threads both read and write from this database. Whenever I do a write, I have the following construct: try: Cursor.execute(q, params) Connection.commit() except sqlite3.IntegrityError: Notify except sqlite3.OperationalError: print sys.exc_info() print("DATABASE LOCKED; sleeping for 3 seconds and trying again") time.sleep(3) Retry On some runs, I won't even hit this block, but when I do, it never comes out of it (keeps retrying, but I keep getting the 'database is locked' error from exc_info. If I understand the reader/writer lock usage correctly, some amount of waiting should help with the contention. What this sounds like is deadlock, but I do not use any transactions in my code, and every SELECT or INSERT is simply a one off. Some threads, however, keep the same connection when they do their operation (which includes a mix of SELECTS and INSERTS and other modifiers). I would appericiate it if you could shade a light on this, and also ways around fixing it (besides using a different database engine.)

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• Is DB logging more secure than file logging for my PHP web app?

  - by iama

  I would like to log errors/informational and warning messages from within my web application to a log. I was initially thinking of logging all of these onto a text file. However, my PHP web app will need write access to the log files and the folder housing this log file may also need write access if log file rotation is desired which my web app currently does not have. The alternative is for me to log the messages to the MySQL database since my web app is already using the MySQL database for all its data storage needs. However, this got me thinking that going with the MySQL option is much better than the file option since I already have a configuration file with the database access information protected using file system permissions. If I now go with the log file option I need to tinker the file and folder access permissions and this will only make my application less secure and defeats the whole purpose of logging. Is this correct? I am using XAMPP for development and am a newbie to LAMP. Please let me know your recommendations for logging. Thanks.

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• Model-binding an object from the repository by several keys

  - by Anton

  Suppose the following route: {region}/{storehouse}/{controller}/{action} These two parameters region and storehouse altogether identify a single entity - a Storehouse. Thus, a bunch of controllers are being called in the context of some storehouse. And I'd like to write actions like this: public ActionResult SomeAction(Storehouse storehouse, ...) Here I can read your thoughts: "Write custom model binder, man". I do. However, the question is How to avoid magic strings within custom model binder? Here is my current code: public class StorehouseModelBinder : IModelBinder { readonly IStorehouseRepository repository; public StorehouseModelBinder(IStorehouseRepository repository) { this.repository = repository; } public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) { var region = bindingContext.ValueProvider.GetValue("region").AttemptedValue; var storehouse = bindingContext.ValueProvider.GetValue("storehouse").AttemptedValue; return repository.GetByKey(region, storehouse); } } If there was a single key, bindingContext.ModelName could be used... Probably, there is another way to supply all the actions with a Storehouse object, i.e. declaring it as a property of the controller and populating it in the Controller.Initialize.

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• functions with same names in javascript

  - by biju

  Hi, I tried to write a function on a js file and another function with the same name in the page.I expected an error but no error came and i got only the function from the js file to execute.How is this possible.Even if i write a function in a separate js file,everything is rendered in a single html file.Then how come it is possible <script type="text/javascript" language="javascript" src="JScript.js" /> <script language="javascript"> function Boo() { alert("Hai new"); } </script> <head runat="server"> <title></title> </head> <body> <form id="form1" runat="server"> <div> <asp:Button runat=server OnClientClick="Boo();" Text="Click" /> </div> </form> </body> and in the js file function Boo() { alert("Hai"); }

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• cat contents of one file into another file

  - by Attila O.

  I have a large (binary) file that has some corruption near the beginning. Then, I have a second, smaller file that I obtain by starting to download the same file again, but interrupt after I have enough bytes to fix the original one. My question is, how do I simply overwrite the beginning of the large file with the contents of the second, smaller file? I could use cat, tail and head, but that would create a copy of the file. There must be a more efficient way. Oh yes, and I'm looking for a linux command-line solution, if that wasn't obvious. I'm using bash, but I have other shells if that helps.

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• javascript, php, cookies

  - by kennedy

  When i declare mac = 123, my internet explorer and firefox will keep refresh non-stop. And if i declare mac = getMacAddress it returns a value 1... I'm able to do a document.write(getMacAddress()) and it would able to display the mac address nicely. 1) Why my explorer will keep refreshing non-stop when i code it manually with "123" 2) why is the document.write able to display out, and when i store it to the cookie, somehow it didnt mange to capture into the cookie and it return a value of "1". Anyone help? create_users.php <script language="JavaScript"> function getMacAddress(){ document.macaddressapplet.setSep( "-" ); return (document.macaddressapplet.getMacAddress()); } function setCookie(c_name,value) { document.cookie = c_name + "=" +escape(value); } //error checking //var mac = getMacAddress(); var mac = "123"; setCookie('cookie_name',mac); window.location = "checkAvailability.php"; </script> checkAvailability.php $javascript_cookie_value = isset($_COOKIE["cookie_name"]) ? $_COOKIE["cookie_name"] : 1; mysql_query("INSERT INTO test (mac) VALUES ('$javascript_cookie_value')");

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• Queries within queries: Is there a better way?

  - by mririgo

  As I build bigger, more advanced web applications, I'm finding myself writing extremely long and complex queries. I tend to write queries within queries a lot because I feel making one call to the database from PHP is better than making several and correlating the data. However, anyone who knows anything about SQL knows about JOINs. Personally, I've used a JOIN or two before, but quickly stopped when I discovered using subqueries because it felt easier and quicker for me to write and maintain. Commonly, I'll do subqueries that may contain one or more subqueries from relative tables. Consider this example: SELECT (SELECT username FROM users WHERE records.user_id = user_id) AS username, (SELECT last_name||', '||first_name FROM users WHERE records.user_id = user_id) AS name, in_timestamp, out_timestamp FROM records ORDER BY in_timestamp Rarely, I'll do subqueries after the WHERE clause. Consider this example: SELECT user_id, (SELECT name FROM organizations WHERE (SELECT organization FROM locations WHERE records.location = location_id) = organization_id) AS organization_name FROM records ORDER BY in_timestamp In these two cases, would I see any sort of improvement if I decided to rewrite the queries using a JOIN? As more of a blanket question, what are the advantages/disadvantages of using subqueries or a JOIN? Is one way more correct or accepted than the other?

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• Homebrew build with different arch?

  - by StasM

  I tried to install mysql-connector-c recipe via homebrew, and it builds just fine, but produces x86_64 library: $file ~/brew/lib/libmysql.dylib .../brew/lib/libmysql.dylib: Mach-O 64-bit dynamically linked shared library x86_64 I however need i386 library for my project. I tried to give it CFLAGS and LDFLAGS like this: CFLAGS="-arch i386 -arch x86_64" LDFLAGS="-arch i386 -arch x86_64" brew install mysql-connector-c but nothing changes - it still builds x86_64 only binary. Is there any way to make homebrew build either dual arch library or i386 library? I have kernel architecture set to x86_64, if it matters.

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• How to create a generic C free function .

  - by nomemory

  I have some C structures related to a 'list' data structure. They look like this. struct nmlist_element_s { void *data; struct nmlist_element_s *next; }; typedef struct nmlist_element_s nmlist_element; struct nmlist_s { void (*destructor)(void *data); int (*cmp)(const void *e1, const void *e2); unsigned int size; nmlist_element *head; nmlist_element *tail; }; typedef struct nmlist_s nmlist; This way I can have different data types being hold in "nmlist_element-data" . The "constructor" (in terms of OOP) has the following signature: nmlist *nmlist_alloc(void (*destructor)(void *data)); Where "destructor" is specific function that de-allocated "data" (being hold by the nmlist_element). If I want to have a list containing integers as data, my "destructor" would like this: void int_destructor(void *data) { free((int*)data); } Still i find it rather "unfriendly" for me to write a destructor functions for every simple primitive data type. So is there a trick to write something like this ? (for primitives): void "x"_destructor(void *data, "x") { free(("x" *)data); } PS: I am not a macro fan myself, and in my short experience regarding C, i don't use them, unless necessary.

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• Trying to create a .NET DLL to be used with Non-.NET Application

  - by Changeling

  I am trying to create a .NET DLL so I can use the cryptographic functions with my non .NET application. I have created a class library so far with this code: namespace AESEncryption { public class EncryptDecrypt { private static readonly byte[] optionalEntropy = { 0x21, 0x05, 0x07, 0x08, 0x27, 0x02, 0x23, 0x36, 0x45, 0x50 }; public interface IEncrypt { string Encrypt(string data, string filePath); }; public class EncryptDecryptInt:IEncrypt { public string Encrypt(string data, string filePath) { byte[] plainKey; try { // Read in the secret key from our cipher key store byte[] cipher = File.ReadAllBytes(filePath); plainKey = ProtectedData.Unprotect(cipher, optionalEntropy, DataProtectionScope.CurrentUser); // Convert our plaintext data into a byte array byte[] plainTextBytes = Encoding.ASCII.GetBytes(data); MemoryStream ms = new MemoryStream(); Rijndael alg = Rijndael.Create(); alg.Mode = CipherMode.CBC; alg.Key = plainKey; alg.IV = optionalEntropy; CryptoStream cs = new CryptoStream(ms, alg.CreateEncryptor(), CryptoStreamMode.Write); cs.Write(plainTextBytes, 0, plainTextBytes.Length); cs.Close(); byte[] encryptedData = ms.ToArray(); return Convert.ToString(encryptedData); } catch (Exception ex) { return ex.Message; } } } } } In my VC++ application, I am using the #import directive to import the TLB file created from the DLL, but the only available functions are _AESEncryption and LIB_AES etc I don't see the interface or the function Encrypt. When I try to instantiate so I can call the functions in my VC++ program, I use this code and get the following error: HRESULT hr = CoInitialize(NULL); IEncryptPtr pIEncrypt(__uuidof(EncryptDecryptInt)); error C2065: 'IEncryptPtr': undeclared identifier error C2146: syntax error : missing ';' before identifier 'pIEncrypt'

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• Text piped to PowerShell.exe isn't recieved when using [Console]::ReadLine()

  - by crtracy

  I'm getting itermittent data loss when calling .NET [Console]::ReadLine() to read piped input to PowerShell.exe: >ping localhost | powershell -NonInteractive -NoProfile -C "do {$line = [Console]::ReadLine(); ('' + (Get-Date -f 'HH:mm :ss') + $line) | Write-Host; } while ($line -ne $null)" 23:56:45time<1ms 23:56:45 23:56:46time<1ms 23:56:46 23:56:47time<1ms 23:56:47 23:56:47 Normally 'ping localhost' from Vista64 looks like this, so there is a lot of data missing from the output above: Pinging WORLNTEC02.bnysecurities.corp.local [::1] from ::1 with 32 bytes of data: Reply from ::1: time<1ms Reply from ::1: time<1ms Reply from ::1: time<1ms Reply from ::1: time<1ms Ping statistics for ::1: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 0ms, Maximum = 0ms, Average = 0ms But using the same API from C# recieves all the data sent to the process (excluding some newline differences). Code: namespace ConOutTime { class Program { static void Main (string[] args) { string s; while ((s = Console.ReadLine ()) != null) { if (s.Length > 0) // don't write time for empty lines Console.WriteLine("{0:HH:mm:ss} {1}", DateTime.Now, s); } } } } Output: 00:44:30 Pinging WORLNTEC02.bnysecurities.corp.local [::1] from ::1 with 32 bytes of data: 00:44:30 Reply from ::1: time<1ms 00:44:31 Reply from ::1: time<1ms 00:44:32 Reply from ::1: time<1ms 00:44:33 Reply from ::1: time<1ms 00:44:33 Ping statistics for ::1: 00:44:33 Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), 00:44:33 Approximate round trip times in milli-seconds: 00:44:33 Minimum = 0ms, Maximum = 0ms, Average = 0ms So, if calling the same API from PowerShell instead of C# many parts of StdIn get 'eaten'. Is the PowerShell host reading string from StdIn even though I didn't use 'PowerShell.exe -Command -'?

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• .NET: Control Invoke() in Reflector

  - by sheepsimulator

  So, I was getting back into some .NET programming, and through a new feature in VS.NET 2010, it detected a case where I was trying to modify a control from a thread that didn't create that control, and pointed me to an article on MSDN about how you do this correctly... ' HOW TO WRITE TO A FORM CONTROL FROM A THREAD THAT DIDN'T CREATE THE CONTROL ' =========================================================================== ' Say you need to write to a UI text box that logs stuff... Delegate Sub WriteLogDelegate(ByVal [text] As String) Private Sub WriteLog(ByVal [text] As String) If Me.rtfLog.InvokeRequired Then ' We are not in the same thread! ' Create new WriteLogDelegate and invoke it on the same thread Dim d As New WriteLogDelegate(AddressOf WriteLog) Me.rtfLog.Invoke(d, New Object() {[text]}) Else ' We are totally in the same thread... ' Call AppendText like normal! Me.rtfLog.AppendText([text]) End If End Sub AND I WAS SO EXCITED BECAUSE I HAVE BEEN PUZZLED BY HOW TO DO THIS FOR LIKE 5 YEARS BECAUSE PREVIOUS VERSIONS OF VS.NET DIDN'T FLAG THIS SINCE I WAS AN UNDERGRAD ON A PROJECT AND... Umm... Sorry bout that. Composure regained. Anyway, now that I know this bit of .NET-fu, I'd like to learn more about what's going on and how it works. Where can I find the code for Invoke() in .NET Reflector?

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• How do I patch a Windows API at runtime so that it to returns 0 in x64?

  - by Jorge Vasquez

  In x86, I get the function address using GetProcAddress() and write a simple XOR EAX,EAX; RET; in it. Simple and effective. How do I do the same in x64? bool DisableSetUnhandledExceptionFilter() { const BYTE PatchBytes[5] = { 0x33, 0xC0, 0xC2, 0x04, 0x00 }; // XOR EAX,EAX; RET; // Obtain the address of SetUnhandledExceptionFilter HMODULE hLib = GetModuleHandle( _T("kernel32.dll") ); if( hLib == NULL ) return false; BYTE* pTarget = (BYTE*)GetProcAddress( hLib, "SetUnhandledExceptionFilter" ); if( pTarget == 0 ) return false; // Patch SetUnhandledExceptionFilter if( !WriteMemory( pTarget, PatchBytes, sizeof(PatchBytes) ) ) return false; // Ensures out of cache FlushInstructionCache(GetCurrentProcess(), pTarget, sizeof(PatchBytes)); // Success return true; } static bool WriteMemory( BYTE* pTarget, const BYTE* pSource, DWORD Size ) { // Check parameters if( pTarget == 0 ) return false; if( pSource == 0 ) return false; if( Size == 0 ) return false; if( IsBadReadPtr( pSource, Size ) ) return false; // Modify protection attributes of the target memory page DWORD OldProtect = 0; if( !VirtualProtect( pTarget, Size, PAGE_EXECUTE_READWRITE, &OldProtect ) ) return false; // Write memory memcpy( pTarget, pSource, Size ); // Restore memory protection attributes of the target memory page DWORD Temp = 0; if( !VirtualProtect( pTarget, Size, OldProtect, &Temp ) ) return false; // Success return true; } This example is adapted from code found here: http://www.debuginfo.com/articles/debugfilters.html#overwrite .

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• New record may be written twice in clusterd index structure

  - by Cupidvogel

  As per the article at Microsoft, under the Test 1: INSERT Performance section, it is written that For the table with the clustered index, only a single write operation is required since the leaf nodes of the clustered index are data pages (as explained in the section Clustered Indexes and Heaps), whereas for the table with the nonclustered index, two write operations are required—one for the entry into the index B-tree and another for the insert of the data itself. I don't think that is necessarily true. Clustered Indexes are implemented through B+ tree structures, right? If you look at at this article, which gives a simple example of inserting into a B+ tree, we can see that when 8 is initially inserted, it is written only once, but then when 5 comes in, it is written to the root node as well (thus written twice, albeit not initially at the time of insertion). Also when 8 comes in next, it is written twice, once at the root and then at the leaf. So won't it be correct to say, that the number of rewrites in case of a clustered index is much less compared to a NIC structure (where it must occur every time), instead of saying that rewrite doesn't occur in CI at all?

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• Is there a good way to copy a Gtk widget?

  - by Jake

  Is there a way, using the Gtk library in C, to clone a Gtk button (for instance), and pack it somewhere else in the app. I know you can't pack the same widget twice. And that this code obviously wouldn't work, but shows what happens when I attempt a shallow copy of the button: GtkButton *a = g_object_new(GTK_TYPE_BUTTON, "label", "o_0", NULL); GtkButton *b = g_memdup(b, sizeof *b); gtk_box_pack_start_defaults(GTK_BOX(vbox), GTK_WIDGET(b)); There is surrounding code which creates a vbox and packs it in a window and runs gtk_main(). This will result in these hard to understand error messages: (main:6044): Gtk-CRITICAL **: gtk_widget_hide: assertion `GTK_IS_WIDGET (widget)' failed (main:6044): Gtk-CRITICAL **: gtk_widget_realize: assertion `GTK_WIDGET_ANCHORED (widget) || GTK_IS_INVISIBLE (widget)' failed ** Gtk:ERROR:/build/buildd/gtk+2.0-2.18.3/gtk/gtkwidget.c:8431:gtk_widget_real_map: assertion failed: (GTK_WIDGET_REALIZED (widget)) Along the same lines, if I were to write my own GObject (not necessarily a Gtk widget), is there a good way to write a copy constructor. Im thinking it should be an interface with optional hooks and based mostly on the properties, handling the class's hierarchy in some way. I'd want to do this: GtkButton *b = copyable_copy(COPYABLE(a)); If GtkButton could use a theoretical copyable interface.

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• How does scope in Javascript work?

  - by Jim

  I can not understand how scoping works in Javascript. E.g. <html> <head> <script>var userName = "George"; </script> </head> <body> ...... <script> document.write('Name = ' + userName); </script> </body> </html> The variable userName is declared in another "section" of a script. As I understand it the browser renders html and executes code in the order it finds it. So how does userName in the second script tag gets resolved? Does it go to a global setting? Anything I declare earlier is global? I noticed the same happens if I do something like: <html> <head> <script> do { var userName = "George"; //bla } while (someCondition); </script> </head> <body> ...... <script> document.write('Name = ' + userName); </script> </body> </html> Even when userName is declared inside {} it is still resolved in the second script. How is that possible?

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• [F#] Parallelize code in nested loops

  - by Juliet

  You always hear that functional code is inherently easier to parallelize than non-functional code, so I decided to write a function which does the following: Given a input of strings, total up the number of unique characters for each string. So, given the input [ "aaaaa"; "bbb"; "ccccccc"; "abbbc" ], our method will returns a: 6; b: 6; c: 8. Here's what I've written: (* seq<#seq<char>> -> Map<char,int> *) let wordFrequency input = input |> Seq.fold (fun acc text -> (* This inner loop can be processed on its own thread *) text |> Seq.choose (fun char -> if Char.IsLetter char then Some(char) else None) |> Seq.fold (fun (acc : Map<_,_>) item -> match acc.TryFind(item) with | Some(count) -> acc.Add(item, count + 1) | None -> acc.Add(item, 1)) acc ) Map.empty This code is ideally parallelizable, because each string in input can be processed on its own thread. Its not as straightforward as it looks since the innerloop adds items to a Map shared between all of the inputs. I'd like the inner loop factored out into its own thread, and I don't want to use any mutable state. How would I re-write this function using an Async workflow?

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• how to send on users profile page on selecting username( using json autosuggest script)

  - by I Like PHP

  i m using auto suggest using Ajax Json . now when a user select a user name , i want to send user on the link of that user name my json data is coming in this way { query:'hel', suggestions:["hello world","hell boy ","bac to hell"], data:["2","26","34"] } now what i want that user goes to http://userProfile.php?uid=26 on select username(suppose user select "hell boy") how to do this?? UPDATE: i describe what i m doing step by step i m using a searchbox using jquery ajax, when user write some text on input box , we show (suggest) value regarading their search STEP 1. when user write atleast(2 letter) <input type="text" name="q" id="query" />then a function(below) in invoked in which i send the value written on text box(eg. hell). <script type="text/javascript" language="javascript"> var options, a; jQuery(function(){ options = { serviceUrl:'rpc.php' }; var a = $('#query').autocomplete({ serviceUrl:'rpc.php', minChars:3, delimiter: /(,|;)\s*/, // regex or character maxHeight:400, width:300, zIndex: 9999, deferRequestBy: 0, //miliseconds }); }); </script> STEP 3: on rpc.php, i collect the data and show using JSON my final data come in below format { query:'hell', suggestions:["hello world","hell boy ","bac to hell"], data:["2","26","34"] } where suggestion list having username and data is userid( from user_tables). above data comes in a div (on frontend) where user name displayed in a list STEP 4: now if i select any username using uparrow, downarrow then that name is filled in input box, STEP 5: now what i want that when user select usename then page automatically goes to that user's profile section ( userprofile.php?uid=2)

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• Snow Leopard, PHP, and MySQL

  - by Peter

  I have just installed Snow Leopard and now my PHP/MySQL program ends in a "Segmentation fault". I have been searching the web for a solution, I realize that there are some issues with SL/PHP/MySQL, but I have not found anything that works yet. I downloaded the binary MySQL package mysql-5.1.42-osx10.6-x86_64. I have updated the php.ini file as suggested at various posts. When I run PHP and connect to the MySQL server the behavior is a bit random. In many cases it works fine to connect and read data. In my specific case the PHP program constructs a LOAD DATA LOCAL INFILE ... statement to load data from a text file. It should do several such queries after each other in a loop. It works one time but the halts in a "Segmentation fault". The program worked fine in Leopard, but not now. My versions are: OS 10.6.2, PHP 5.3.0, MySQL 5.1.42

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• No idea how to solve SICP exercise 1.11

  - by Javier Badia

  This is not homework. Exercise 1.11: A function f is defined by the rule that f(n) = n if n<3 and f(n) = f(n - 1) + 2f(n - 2) + 3f(n - 3) if n 3. Write a procedure that computes f by means of a recursive process. Write a procedure that computes f by means of an iterative process. Implementing it recursively is simple enough. But I couldn't figure out how to do it iteratively. I tried comparing with the Fibonacci example given, but I didn't know how to use it as an analogy. So I gave up (shame on me) and Googled for an explanation, and I found this: (define (f n) (if (< n 3) n (f-iter 2 1 0 n))) (define (f-iter a b c count) (if (< count 3) a (f-iter (+ a (* 2 b) (* 3 c)) a b (- count 1)))) After reading it, I understand the code and how it works. But what I don't understand is the process needed to get from the recursive defintion of the function to this. I don't get how the code formed in someone's head. Could you explain the thought process needed to arrive at the solution?

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• Need Help finding an appropriate task asignment algoritm for a collage project involving coordinatin

  - by Trif Mircea

  Hello. I am a long time lurker here and have found over time many answers regarding jquery and web development topics so I decided to ask a question of my own. This time I have to create a c++ project for collage which should help manage the workflow of a company providing all kinds of services through in the field teams. The ideas I have so far are: client-server application; the server is a dispatcher where all the orders from clients get and the clients are mobile devices (PDAs) each team in the field having one a order from a client is a task. Each task is made up of a series of subtasks. You have a database with estimations on how long a task should take to complete you also know what tasks or subtasks each team on the field can perform based on what kind of specialists made up the team (not going to complicate the problem by adding needed materials, it is considered that if a member of a team can perform a subtask he has the stuff needed) Now knowing these factors, what would a good task assignment algorithm be? The criteria is: how many tasks can a team do, how many tasks they have in the queue, it could also be location, how far away are they from the place but I don't think I can implement that.. It needs to be efficient and also to adapt quickly is the human dispatcher manually assigns a task. Any help or leads would be really appreciated. Also I'm not 100% sure in the idea so if you have another way you would go about creating such an application please share, even if it just a quick outline. I have to write a theoretical part too so even if the ideas are far more complex that what i outlined that would be ok ; I'd write those and implement what I can.

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• The perfect web UI framework (with Microsoft stack?) - architecture question?

  - by Igorek

  I'm looking for suggestions for the following issue, and I realize there is really not going to be a perfect answer to my question: I have a UI built in WinForms.NET (v4.0 framework) with WCF back-end and EF4 model objects, that I am looking to port to the web. UI is not huge and is not super complex and is structured well. But it is not a super simple system either. I am looking to pick a technology stack for the web-frontend that will target desktop & partially mobile platforms, provide a good development platform to build on, and facilitate code reuse across UI and back-end tiers... I would rather avoid: custom coding of UI-centric scripts, because they are hard to debug, non-compiled, usually a maintenance nightmare, almost always start to contain business logic, and duplicate some of the logic that back-end tiers have (especially validation) custom-coding for Desktop Web and Mobile Web UI's separately (although I realize that mobile web UI will likely contain fewer of data-entry screens and more reporting screens) non-.NET technology stacks I would love to: target the reporting capabilities of the system toward mobile web browsers not have to write a single line of script (javascript, jquery, etc.) utilize a good collection of controls that produces an elegant UI use .NET for everything The way I see it right now, I need to re-write this app in Silverlight, utilize a 3rd party UI framework like Telerik, and re-do the reports UI again for mobile platforms separately. However, I'm rather concerned about the shelf-life of Silverlight and the needed to deploy a different architecture to deal with mobile platform. Is there an ASP.NET/MVC/Ajax architecture/framework/library that would allow me to get at the power of .NET and without painful (imho) client-side scripting, while providing a decent user experience Thank you

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• Are there supposed to be more restrictions on operator->* overloads?

  - by Potatoswatter

  I was perusing section 13.5 after refuting the notion that built-in operators do not participate in overload resolution, and noticed that there is no section on operator->*. It is just a generic binary operator. Its brethren, operator->, operator*, and operator[], are all required to be non-static member functions. This precludes definition of a free function overload to an operator commonly used to obtain a reference from an object. But the uncommon operator->* is left out. In particular, operator[] has many similarities. It is binary (they missed a golden opportunity to make it n-ary), and it accepts some kind of container on the left and some kind of locator on the right. Its special-rules section, 13.5.5, doesn't seem to have any actual effect except to outlaw free functions. (And that restriction even precludes support for commutativity!) So, for example, this is perfectly legal (in C++0x, remove obvious stuff to translate to C++03): #include <utility> #include <iostream> #include <type_traits> using namespace std; template< class F, class S > typename common_type< F,S >::type operator->*( pair<F,S> const &l, bool r ) { return r? l.second : l.first; } template< class T > T & operator->*( pair<T,T> &l, bool r ) { return r? l.second : l.first; } template< class T > T & operator->*( bool l, pair<T,T> &r ) { return l? r.second : r.first; } int main() { auto x = make_pair( 1, 2.3 ); cerr << x->*false << " " << x->*4 << endl; auto y = make_pair( 5, 6 ); y->*(0) = 7; y->*0->*y = 8; // evaluates to 7->*y = y.second cerr << y.first << " " << y.second << endl; } I can certainly imagine myself giving into temp[la]tation. For example, scaled indexes for vector: v->*matrix_width[5] = x; Did the standards committee forget to prevent this, was it considered too ugly to bother, or are there real-world use cases?

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