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  • Modify existing struct alignment in Visual C++

    - by Crend King
    Is there a way to modify the member alignment of an existing struct in Visual C++? Here is the background: I use an 3rd-party library, which uses several structs. To fill up the structs, I pass the address of the struct instance to some functions. Unfortunately, the functions only returns unaligned buffer, so that data of some members are always wrong. /Zp is out of choice, since it breaks the other parts of the program. I know #pragma pack modifies the alignment of the following struct, but I do not want to copy the structs into my code, for the definitions in the library might change in the future. Sample code: test.h: struct am_aligned { BYTE data1[10]; ULONG data2; }; test.cpp: include "test.h" // typedef alignment(1) struct am_aligned am_unaligned int APIENTRY wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { char buffer[20] = {}; for (int i = 0; i < sizeof(unaligned_struct); i++) { buffer[i] = i; } am_aligned instance = *(am_aligned*) buffer; return 0; } instance.data2 is 0x0f0e0d0c, while 0x0d0c0b0a is desired. The commented line does not work of course. Thanks for help!

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  • Any utility to test expand C/C++ #define macros?

    - by Randy
    It seems I often spend way too much time trying to get a #define macro to do exactly what i want. I'll post my current delemia below and any help is appreciated. But really the bigger question is whether there is any utility someone could reccomend, to quickly display what a macro is actually doing? It seems like even the slow trial and error process would go much faster if I could see what is wrong. Currently, I'm dynamically loading a long list of functions from a DLL I made. The way I've set things up, the function pointers have the same nanes as the exported functions, and the typedef(s) used to prototyp them have the same names, but with a prepended underscor. So I want to use a define to simplfy assignments of a long long list of function pointers. For example, In the code statement below, 'hexdump' is the name of a typdef'd function point, and is also the name of the function, while _hexdump is the name of the typedef. If GetProcAddress() fails, a failure counter in incremented. if (!(hexdump = (_hexdump)GetProcAddress(h, "hexdump"))) --iFail; So lets say I'd like to rplace each line like the above with a macro, like this... GETADDR_FOR(hexdump ) Well this is the best I've come up with so far. It doesn't work (my // comment is just to prevent text formatting in the message)... // #define GETADDR_FOR(a) if (!(a = (#_#a)GetProcAddress(h, "/""#a"/""))) --iFail; And again, while I'd APPRECIATE an insight into what silly mistake I've made, it would make my day to have a utility that would show me the error of my ways, by simply plugging in my macro

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  • MSVC 2003 doesn't see any definitions from a nested include file

    - by ezpresso
    I have a piece of code with COM class declaration as follows: #include "PathTypes.h" MIDL_INTERFACE("552C7555-0555-4444-BA86-56CF39AAFFFF") IPathCalc : public IUnknown { virtual HRESULT STDMETHODCALLTYPE GetLocation( /* [retval][out] */ GeoLocation* pLoc) = 0; virtual HRESULT STDMETHODCALLTYPE SetLocation( /* [in] */ GeoLocation* pLoc) = 0; ... }; Below is the contents of PathTypes.h file: #if !defined(PATHCALC_TYPES_INCLUDED) #define PATHCALC_TYPES_INCLUDED #include "libastro/AstronomyStructs.h" #endif And the libastro/AstronomyStructs.h from an external cross-platform library: #ifndef _ASTRONOMY_STRUCTS_INCLUDED #define _ASTRONOMY_STRUCTS_INCLUDED typedef struct { double lattitude; double longitude; } GeoLocation; ... #endif /* _ASTRONOMY_STRUCTS_INCLUDED */ When I'm trying to build this code with g++ everything goes well. That's not the case with MSVC 2003 which returns error C2061: syntax error : identifier 'GeoLocation'. Seems like MSVC doesn't "see" the definitions from the libastro/AstronomyStructs.h file. When I replace #include "PathTypes.h" with #include "libastro/AstronomyStructs.h" the code compiles without errors. How to make MSVC 2003 to actually "see" the definitions from the nested include files?

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  • How to deal with seniors' bad coding style/practices?

    - by KaluSingh Gabbar
    I am new to work but the company I work in hires a lot of non-comp-science people who are smart enough to get the work done (complex) but lack the style and practices that should help other people read their code. For example they adopt C++ but still use C-like 3 page functions which drives new folks nuts when they try to read that. Also we feel very risky changing it as it's never easy to be sure we are not breaking something. Now, I am involved in the project with these guys and I can't change the entire code base myself or design so that code looks good, what can I do in this situation? PS we actually have 3 page functions & because we do not have a concept of design, all we can do is assume what they might have thought as there is no way to know why is it designed the way it is. I am not complaining.I am asking for suggestion,already reading some books to solve the issues Pragmatic Programmer; Design portion from B.Stroustrup; Programming and principles by B.Stroustrup;

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  • How to write an intersects for Shapes in android

    - by Rafael T
    I have an written an Object called Shape which has a Point representing the topLeftCorner and a Dimension with represents its width and height. To get the topRightCorner I can simply add the width to the topLeftPoint.x. I use to rotate them on a certain degree around their center. The problem after the rotation is, that my intersects(Shape) method fails, because it does not honor the rotation of the Shapes. The rotation will be the same for each Shape. My current implementation looks like this inside my Shape Object: public boolean intersects(Shape s){ // functions returning a Point of shape s return intersects(s.topLeft()) || intersects(s.topRight()) || intersects(s.bottomLeft()) || intersects(s.bottomRight()) || intersects(s.leftCenter()) || intersects(s.rightCenter()) || intersects(s.center()); } public boolean intersects(Point p){ return p.x >= leftX() && p.x <= rightX() && p.y >= topY() && p.y <= bottomY(); } Basically I need functions like rotatedLeftX() or rotatedTopRight() to work properly. Also for that calculation I think it doesn't matter when the topLeft point before a rotation of ie 90 will turn into topRight... I already read this and this Question here, but do not understand it fully.

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  • How to pass data to a C++0x lambda function that will run in a different thread?

    - by Dimitri C.
    In our company we've written a library function to call a function asynchronously in a separate thread. It works using a combination of inheritance and template magic. The client code looks as follows: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, &DemoThread::SomeFunction, stringToPassByValue); Since the introduction of lambda functions I'd like to use it in combination with lambda functions. I'd like to write the following client code: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, [=]() { const std::string someCopy = stringToPassByValue; }); Now, with the Visual C++ 2010 this code doesn't work. What happens is that the stringToPassByValue is not copied. Instead the "capture by value" feature passes the data by reference. The result is that if the function is executed after stringToPassByValue has gone out of scope, the application crashes as its destructor is called already. So I wonder: is it possible to pass data to a lambda function as a copy? Note: One possible solution would be to modify our framework to pass the data in the lambda parameter declaration list, as follows: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, [=](const std::string stringPassedByValue) { const std::string someCopy = stringPassedByValue; } , stringToPassByValue); However, this solution is so verbose that our original function pointer solution is both shorter and easier to read. Update: The full implementation of AsyncCall is too big to post here. In short, what happens is that the AsyncCall template function instantiates a template class holding the lambda function. This class is derived from a base class that contains a virtual Execute() function, and upon an AsyncCall() call, the function call class is put on a call queue. A different thread then executes the queued calls by calling the virtual Execute() function, which is polymorphically dispatched to the template class which then executes the lambda function.

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  • Omit return type in C++0x

    - by Clinton
    I've recently found myself using the following macro with gcc 4.5 in C++0x mode: #define RETURN(x) -> decltype(x) { return x; } And writing functions like this: template <class T> auto f(T&& x) RETURN (( g(h(std::forward<T>(x))) )) I've been doing this to avoid the inconvenience having to effectively write the function body twice, and having keep changes in the body and the return type in sync (which in my opinion is a disaster waiting to happen). The problem is that this technique only works on one line functions. So when I have something like this (convoluted example): template <class T> auto f(T&& x) -> ... { auto y1 = f(x); auto y2 = h(y1, g1(x)); auto y3 = h(y1, g2(x)); if (y1) { ++y3; } return h2(y2, y3); } Then I have to put something horrible in the return type. Furthermore, whenever I update the function, I'll need to change the return type, and if I don't change it correctly, I'll get a compile error if I'm lucky, or a runtime bug in the worse case. Having to copy and paste changes to two locations and keep them in sync I feel is not good practice. And I can't think of a situation where I'd want an implicit cast on return instead of an explicit cast. Surely there is a way to ask the compiler to deduce this information. What is the point of the compiler keeping it a secret? I thought C++0x was designed so such duplication would not be required.

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  • How can I send GET data to multiple URLs at the same time using cURL?

    - by Rob
    My apologies, I've actually asked this question multiple times, but never quite understood the answers. Here is my current code: while($resultSet = mysql_fetch_array($SQL)){ $ch = curl_init($resultSet['url'] . $fullcurl); //load the urls and send GET data curl_setopt($ch, CURLOPT_TIMEOUT, 2); //Only load it for two seconds (Long enough to send the data) curl_exec($ch); //Execute the cURL curl_close($ch); //Close it off } //end while loop What I'm doing here, is taking URLs from a MySQL Database ($resultSet['url']), appending some extra variables to it, just some GET data ($fullcurl), and simply requesting the pages. This starts the script running on those pages, and that's all that this script needs to do, is start those scripts. It doesn't need to return any output. Just the load the page long enough for the script to start. However, currently it's loading each URL (currently 11) one at a time. I need to load all of them simultaneously. I understand I need to use curl_multi_*, but I haven't the slightest idea on how cURL functions work, so I don't know how to change my code to use curl_multi_* in a while loop. So my questions are: How can I change this code to load all of the URLs simultaneously? Please explain it and not just give me code. I want to know what each individual function does exactly. Will curl_multi_exec even work in a while loop, since the while loop is just sending each row one at a time? And of course, any references, guides, tutorials about cURL functions would be nice, as well. Preferably not so much from php.net, as while it does a good job of giving me the syntax, its just a little dry and not so good with the explanations.

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  • Make a form not focusable in C#

    - by Jandex
    Hi! I'm wanting to write a virtual keyboard, like windows onscreen keyboard for touchscreen pcs. But I'm having problem with my virtual keyboard stealing the focus from the application being used. The windows onscreen keyboard mantains the focus on the current application even when the user clicks on it. Is there a way to do the same with windows forms in C#? The only thing I can do for now is to send a keyboard event to an especific application, like notepad in the following code. If I could make the form not focusable, I could get the current focused window with GetForegroundWindow. [DllImport("USER32.DLL", CharSet = CharSet.Unicode)] public static extern IntPtr FindWindow(string lpClassName,string lpWindowName); [DllImport("USER32.DLL")] public static extern bool SetForegroundWindow(IntPtr hWnd); private void button1_Click(object sender, EventArgs e) { IntPtr calculatorHandle = FindWindow("notepad", null); SetForegroundWindow(calculatorHandle); SendKeys.SendWait("111"); } Is there a way this can be done? Any suggestions of a better way to have the form sending keyboard events to the application being used? Thanks!!

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  • What is the difference between these two linq implementations?

    - by Mahesh Velaga
    I was going through Jon Skeet's Reimplemnting Linq to Objects series. In the implementation of where article, I found the following snippets, but I don't get what is the advantage that we are gettting by splitting the original method into two. Original Method: // Naive validation - broken! public static IEnumerable<TSource> Where<TSource>( this IEnumerable<TSource> source, Func<TSource, bool> predicate) { if (source == null) { throw new ArgumentNullException("source"); } if (predicate == null) { throw new ArgumentNullException("predicate"); } foreach (TSource item in source) { if (predicate(item)) { yield return item; } } } Refactored Method: public static IEnumerable<TSource> Where<TSource>( this IEnumerable<TSource> source, Func<TSource, bool> predicate) { if (source == null) { throw new ArgumentNullException("source"); } if (predicate == null) { throw new ArgumentNullException("predicate"); } return WhereImpl(source, predicate); } private static IEnumerable<TSource> WhereImpl<TSource>( this IEnumerable<TSource> source, Func<TSource, bool> predicate) { foreach (TSource item in source) { if (predicate(item)) { yield return item; } } } Jon says - Its for eager validation and then defferring for the rest of the part. But, I don't get it. Could some one please explain it in a little more detail, whats the difference between these 2 functions and why will the validations be performed in one and not in the other eagerly? Conclusion/Solution: I got confused due to my lack of understanding on which functions are determined to be iterator-generators. I assumed that, it is based on signature of a method like IEnumerable<T>. But, based on the answers, now I get it, a method is an iterator-generator if it uses yield statements.

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  • Convert C function to Objective C or alternative way to include C library?

    - by Moshe
    Background: I'm new to Objective-C and I've never touched C before. I'm trying to include a C library in my iPhone/iPod Touch project and I could not successfully compile the library's source code using the included instructions, so I've resorted to including the .h and .c files in Xcode. The library is for Hebrew Dates and corresponding Jewish Holidays. It can be found here: http://sourceforge.net/projects/libhdate/ I cannot seem to import the .c files into my implementation files. I can import the .h files though. When I try to use #import "file.c", where file.c is a file that is in XCode, it doesn't work. Why not? I've considered just writing the functions over in Objective-C, albeit only my needed functions and not the whole library. How can I make the following C function work in Objective-C? Are there other things that need to be included/re-coded/compiled? How so? I am almost certain something is missing, but I'm not sure what. Code: int hdate_get_omer_day(hdate_struct const * h) { int omer_day; hdate_struct sixteen_nissan; hdate_set_hdate(&sixteen_nissan, 16, 7, h->hd_year); omer_day = h->hd_jd - sixteen_nissan.hd_jd + 1; if ((omer_day > 49) || (omer_day < 0)) omer_day = 0; return omer_day; } So... should I be converting it, or trying somehow to compile to an appropriate format and how so? (I don't know what format a static library should be in, by the way, or if it should be static... - I'm so lost here....) I appreciate the help!

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  • Finding What You Need in R: function arguments/parameters from outside the function's package

    - by doug
    Often in R, there are a dozen functions scattered across as many packages--all of which have the same purpose but of course differ in accuracy, performance, theoretical rigor, and so on. How do you gather all of these in one place before you start your task? So for instance: the generic plot function. Setting secondary ticks is much easier (IMHO) using a function outside of the base package, minor.tick(nx=n, ny=n, tick.ratio=n), found in Hmisc. Of course, that doesn't show up in plot's docstring. Likewise, the data-input arguments to 'plot' can be supplied by an object returned from the function 'hexbin', again, from a library outside of the base installation (where 'plot' resides). What would be great obviously is a programmatic way to gather these function arguments from the various libraries and put them in a single namespace. edit: (trying to re-state my example just above more clearly:) the arguments to plot supplied in the base package for, e.g., setting the axis tick frequency are xaxp/yaxp; however, one can also set a/t/f via a function outside of the base package, again, as in the minor.tick function from the Hmisc package--but you wouldn't know that just from looking at the plot method signature. Is there a meta function in R for this? So far, as i come across them, i've been manually gathering them in a TextMate 'snippet' (along with the attendant library imports). This isn't that difficult or time consuming, but i can only update my snippet as i find out about these additional arguments/parameters. Is there a canonical R way to do this, or at least an easier way? Just in case that wasn't clear, i am not talking about the case where multiple packages provide functions directed to the same statistic or view (e.g., 'boxplot' in the base package; 'boxplot.matrix' in gplots; and 'bplots' in Rlab). What i am talking is the case in which the function name is the same across two or more packages.

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  • FluentNHibernate: Not.Nullable() doesn't affect output schema

    - by alex
    Hello I'm using fluent nhibernate v. 1.0.0.595. There is a class: public class Weight { public virtual int Id { get; set; } public virtual double Value { get; set; } } I want to map it on the following table: create table [Weight] ( WeightId INT IDENTITY NOT NULL, Weight DOUBLE not null, primary key (WeightId) ) Here is the map: public class WeightMap : ClassMap<Weight> { public WeightMap() { Table("[Weight]"); Id(x => x.Id, "WeightId"); Map(x => x.Value, "Weight").Not.Nullable(); } } The problem is that this mapping produces table with nullable Weight column: Weight DOUBLE null Not-nullable column is generated only with default convention for column name (i.e. Map(x = x.Value).Not.Nullable() instead of Map(x = x.Value, "Weight").Not.Nullable()), but in this case there will be Value column instead of Weight: create table [Weight] ( WeightId INT IDENTITY NOT NULL, Value DOUBLE not null, primary key (WeightId) ) I found similiar problem here: http://code.google.com/p/fluent-nhibernate/issues/detail?id=121, but seems like mentioned workaround with SetAttributeOnColumnElement("not-null", "true") is outdated. Does anybody encountered with this problem? Is there a way to specify named column as not-nullable?

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  • Sending one record from cursor to another function Postgres

    - by PylonsN00b
    FYI: I am completely new to using cursors... So I have one function that is a cursor: CREATE FUNCTION get_all_product_promos(refcursor, cursor_object_id integer) RETURNS refcursor AS ' BEGIN OPEN $1 FOR SELECT * FROM promos prom1 JOIN promo_objects ON (prom1.promo_id = promo_objects.promotion_id) WHERE prom1.active = true AND now() BETWEEN prom1.start_date AND prom1.end_date AND promo_objects.object_id = cursor_object_id UNION SELECT prom2.promo_id FROM promos prom2 JOIN promo_buy_objects ON (prom2.promo_id = promo_buy_objects.promo_id) LEFT JOIN promo_get_objects ON prom2.promo_id = promo_get_objects.promo_id WHERE (prom2.buy_quantity IS NOT NULL OR prom2.buy_quantity > 0) AND prom2.active = true AND now() BETWEEN prom2.start_date AND prom2.end_date AND promo_buy_objects.object_id = cursor_object_id; RETURN $1; END; ' LANGUAGE plpgsql; SO then in another function I call it and need to process it: ... --Get the promotions from the cursor SELECT get_all_product_promos('promo_cursor', this_object_id) updated := FALSE; IF FOUND THEN --Then loop through your results LOOP FETCH promo_cursor into this_promotion --Preform comparison logic -this is necessary as this logic is used in other contexts from other functions SELECT * INTO best_promo_results FROM get_best_product_promos(this_promotion, this_object_id, get_free_promotion, get_free_promotion_value, current_promotion_value, current_promotion); ... SO the idea here is to select from the cursor, loop using fetch (next is assumed correct?) and put the record fetched into this_promotion. Then send the record in this_promotion to another function. I can't figure out what to declare the type of this_promotion in get_best_product_promos. Here is what I have: CREATE OR REPLACE FUNCTION get_best_product_promos(this_promotion record, this_object_id integer, get_free_promotion integer, get_free_promotion_value numeric(10,2), current_promotion_value numeric(10,2), current_promotion integer) RETURNS... It tells me: ERROR: plpgsql functions cannot take type record OK first I tried: CREATE OR REPLACE FUNCTION get_best_product_promos(this_promotion get_all_product_promos, this_object_id integer, get_free_promotion integer, get_free_promotion_value numeric(10,2), current_promotion_value numeric(10,2), current_promotion integer) RETURNS... Because I saw some syntax in the Postgres docs showed a function being created w/ a input parameter that had a type 'tablename' this works, but it has to be a tablename not a function :( I know I am so close, I was told to use cursors to pass records around. So I studied up. Please help.

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  • memcmp,strcmp,strncmp in C

    - by el10780
    I wrote this small piece of code in C to test memcmp() strncmp() strcmp() functions in C. Here is the code that I wrote: #include <stdio.h> #include <stdlib.h> #include <string.h> int main(int argc, char** argv) { char *word1="apple",*word2="atoms"; if (strncmp(word1,word2,5)==0) printf("strncmp result.\n"); if (memcmp(word1,word2,5)==0) printf("memcmp result.\n"); if (strcmp(word1,word2)==0) printf("strcmp result.\n"); } Can somebody explain me the differences because I am confused with these three functions?My main problem is that I have a file in which I tokenize its line of it,the problem is that when I tokenize the word "atoms" in the file I have to stop the process of tokenizing.I first tried strcmp() but unfortunately when it reached to the point where the word "atoms" were placed in the file it didn't stop and it continued,but when I used either the memcmp() or the strncmp() it stopped and I was happy.But then I thought,what if there will be a case in which there is one string in which the first 5 letters are a,t,o,m,s and these are being followed by other letters.Unfortunately,my thoughts were right as I tested it using the above code by initializing word1 to "atomsaaaaa" and word2 to atoms and memcmp() and strncmp() in the if statements returned 0.On the other hand strcmp() it didn't.It seems that I must use strcmp(). I have done google searches but I got more confused as I have seen sites and other forums to define these three differently.If it is possible for someone to give me correct explanations/definitions so I can use them correctly in my source code,I would be really grateful.

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  • What is the correct high level schema.org microdata itemtype for a retail brand/company homepage?

    - by kpowz
    I'd like to hear which schema.org itemtype others would recommend using or have used in the case of completing a retail brand's company homepage microdata. Take for example TOMS's shoes: Example #1 - Using /Corporation as the high-level itemtype one can include a lot of great /Organization microdata, but nothing about the retail store. <html itemscope='itemscope' itemtype="http://schema.org/Website> <head></head> <body itemscope='itemscope' itemtype="http://schema.org/Corporation> various microdata here probably including Product microdata </body> </html> NOTE: the only schema.org property specific to /Corporation is tickerSymbol & TOMS doesn't have one. Example #2 - This code would work if TOMS started their own channel of physical retail stores & each location had it's own homepage. However, for TOMS's.com, although accurate schematically & more descriptive at the face, this is incorrect microdata markup for TOMS.com, because /ShoeStore derives from /LocalBusiness - which must represent a physical place. <html itemscope='itemscope' itemtype='http://schema.org/Website'> <head></head> <body itemscope='itemscope' itemtype='http://schema.org/ShoeStore'> a whole bunch of jabber here </body> </html> NOTE: Since TOMS is virtual & thus can't be a /Store this means you lose really cool properties like 'currenciesAccepted', 'paymentAccepted' & 'priceRange'. Is this just a 'sit and wait' situation until more schemas are approved for 'virtual places' or is there a validation-passing way to get the best of both worlds?

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  • Analyzing an IronPython Scope

    - by Vercinegetorix
    I'm trying to write C# code with an embedded IronPython script. Then want to analyze the contents of the script, i.e. list all variables, functions, class and their members/methods. There's an easy way to start, assuming I've got a scope defined and code executed in it already: dynamic variables=pyScope.GetVariables(); foreach (string v in variables) { dynamic dynamicV=pyScope.GetVariable(); /*seems to return everything. variables, functions, classes, instances of classes*/ } But how do I figure out what the type of a variable is? For the following python 'objects', dynamicV.GetType() will return different values: x=5 --system.Int32 y="asdf" --system.String def func():... --IronPython.Runtime.PythonFunction z=class() -- IronPython.Runtime.Types.OldInstance, how can I identify what the actual python class is? class NewClass -- throws an error, GetType() is unavailable. This is almost what I'm looking for. I could capture the exception thrown when unavailable and assume it's a class declaration, but that seems unclean. Is there a better approach? To discover the members/methods of a class it looks like I can use: ObjectOperations op = pyEngine.Operations; object instance = op.Call("className"); foreach (string j in op.GetMemberNames("className")) { object member=op.GetMember(instance, j); Console.WriteLine(member.GetType()); /*once again, GetType() provides some info about the type of the member, but returns null sometimes*/ } Also, how do I get the parameters to a method? Thanks!

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  • Fastest way to clamp a real (fixed/floating point) value?

    - by Niklas
    Hi, Is there a more efficient way to clamp real numbers than using if statements or ternary operators? I want to do this both for doubles and for a 32-bit fixpoint implementation (16.16). I'm not asking for code that can handle both cases; they will be handled in separate functions. Obviously, I can do something like: double clampedA; double a = calculate(); clampedA = a > MY_MAX ? MY_MAX : a; clampedA = a < MY_MIN ? MY_MIN : a; or double a = calculate(); double clampedA = a; if(clampedA > MY_MAX) clampedA = MY_MAX; else if(clampedA < MY_MIN) clampedA = MY_MIN; The fixpoint version would use functions/macros for comparisons. This is done in a performance-critical part of the code, so I'm looking for an as efficient way to do it as possible (which I suspect would involve bit-manipulation) EDIT: It has to be standard/portable C, platform-specific functionality is not of any interest here. Also, MY_MIN and MY_MAX are the same type as the value I want clamped (doubles in the examples above).

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  • Different programming languages possibilities

    - by b-gen-jack-o-neill
    Hello. This should be very simple question. There are many programming languages out there, compiled into machine code or managed code. I first started with ASM back in high school. Assembler is very nice, since you know what exactly CPU does. Next, (as you can see from my other questions here) I decided to learn C and C++. I choosed C becouse from what I read it is the language with output most close to assembler-written programs. But, what I want to know is, can any other Windows programming language out there call win32 API? To be exact, like C has its special header and functions for win32 api interactions, is this assumed to be some important part of programming language? Or are there any languages that have no support for calling win32 API, or just use console to IO and some functions for basic file IO? Becouse, for Windows programming with graphic output, it is essential to have acess to win32 API. I know this question might seem silly, but still please, help me, I ask for study porposes. Thanks.

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  • Creating PHP strings using other variables...works manually, can't figure out how automatically

    - by Matt
    Hello, I'm trying to get a variable to be formed automatically using data pulled from a mysql database. I know the data is being pulled from the database in some form resembling its original form, but that data does not act the same as data that is manually typed and assigned to a string. For example, if a cell in a mysql table says... I said "goodbye" before I left. She also said "goodbye." ...and I manually copy/paste it and add the necessary escapes... $string1 = " I said \"goodbye\" before I left. She also said \"goodbye.\" "; ...that does not equal... $string1 = $mysqlResultArray['specificCellWithQuoteShownAbove'] Interestingly, if I echo both versions of $string1 and view the output, they appear to be exactly the same. But they do not function the same when put through various functions I've created. The functions only work if I do the manual copy/paste method--which is not what I want, obviously. I'm not sure if it has to do with the line breaks or the escapes--or some combination of the two. But while both strings are superficially the same, they are apparently functionally different and I don't know why. So how can I create $string1 without manually copy/pasting the contents from the mysql entry and instead querying for the data and assigning it to $string1 in such a way that it's exactly functionally equivalent as the manual copy/pasted string?

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  • Length-1 arrays can be converted to python scalars error? python

    - by Randy
    from numpy import * from pylab import * from math import * def LogisticMap(a,x): return 4.*a*x*(1.-x) def CosineMap(a,x): return a*cos(x/(2.*pi)) def TentMap(a,x): if x>= 0 or x<0.5: return 2.*a*x if x>=0.5 or x<=1.: return 2.*a*(1.-x) a = 0.98 N = 40 xaxis = arange(0.0,N,1.0) Func = CosineMap subplot(211) title(str(Func.func_name) + ' at a=%g and its second iterate' %a) ylabel('X(n+1)') # set y-axis label plot(xaxis,Func(a,xaxis), 'g', antialiased=True) subplot(212) ylabel('X(n+1)') # set y-axis label xlabel('X(n)') # set x-axis label plot(xaxis,Func(a,Func(a,xaxis)), 'bo', antialiased=True) My program is supposed to take any of the three defined functions and plot it. They all take in a value x from the array xaxis from 0 to N and then return the value. I want it to plot a graph of xaxis vs f(xaxis) with f being any of the three above functions. The logisticmap function works fine, but for CosineMap i get the error "only length-1 arrays can be converted to python scalars" and for TentMap i get error "The truth value of an array with more than one element is ambiguous, use a.any() or a.all()". My tent map function is suppose to return 2*a*x if 0<=x<0.5 and it's suppose to return 2*a*(1-x) if 0.5<=0<=1.

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  • Best way to implement plugin framework - are DLLs the only way (C/C++ project)?

    - by Microkernel
    Introduction: I am currently developing a document classifier software in C/C++ and I will be using Naive-Bayesian model for classification. But I wanted the users to use any algorithm that they want(or I want in the future), hence I went to separate the algorithm part in the architecture as a plugin that will be attached to the main app @ app start-up. Hence any user can write his own algorithm as a plugin and use it with my app. Problem Statement: The way I am intending to develop this is to have each of the algorithms that user wants to use to be made into a DLL file and put into a specific directory. And at the start, my app will search for all the DLLs in that directory and load them. My Questions: (1) What if a malicious code is made as a DLL (and that will have same functions mandated by plugin framework) and put into my plugins directory? In that case, my app will think that its a plugin and picks it and calls its functions, so the malicious code can easily bring down my entire app down (In the worst case could make my app as a malicious code launcher!!!). (2) Is using DLLs the only way available to implement plugin design pattern? (Not only for the fear of malicious plugin, but its a generic question out of curiosity :) ) (3) I think a lot of softwares are written with plugin model for extendability, if so, how do they defend against such attacks? (4) In general what do you think about my decision to use plugin model for extendability (do you think I should look at any other alternatives?) Thank you -MicroKernel :)

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  • PHP modifying and combining array

    - by Industrial
    Hi everyone, I have a bit of an array headache going on. The function does what I want, but since I am not yet to well acquainted with PHP:s array/looping functions, so thereby my question is if there's any part of this function that could be improved from a performance-wise perspective? I tried to be as complete as possible in my descriptions in each stage of the functions which shortly described prefixes all keys in an array, fill up eventual empty/non-valid keys with '' and removes the prefixes before returning the array: $var = myFunction ( array('key1', 'key2', 'key3', '111') ); function myFunction ($keys) { $prefix = 'prefix_'; $keyCount = count($keys); // Prefix each key and remove old keys for($i=0;$i<$keyCount; $i++){ $keys[] = $prefix.$keys[$i]; unset($keys[$i]); } // output: array('prefix_key1', 'prefix_key2', 'prefix_key3', '111) // Get all keys from memcached. Only returns valid keys $items = $this->memcache->get($keys); // output: array('prefix_key1' => 'value1', 'prefix_key2' => 'value2', 'prefix_key3'=>'value3) // note: key 111 was not found in memcache. // Fill upp eventual keys that are not valid/empty from memcache $return = $items + array_fill_keys($keys, ''); // output: array('prefix_key1' => 'value1', 'prefix_key2' => 'value2', 'prefix_key3'=>'value3, 'prefix_111' => '') // Remove the prefixes for each result before returning array to application foreach ($return as $k => $v) { $expl = explode($prefix, $k); $return[$expl[1]] = $v; unset($return[$k]); } // output: array('key1' => 'value1', 'key2' => 'value2', 'key3'=>'value3, '111' => '') return $return; } Thanks a lot!

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  • Calling function after .load (Jquery)

    - by Matt
    Having a little difficulty getting a function to call after a .load: $(function(){ $('a.pageFetcher').click(function(){ $('#main').load($(this).attr('rel')); }); }); The page loads, but the functions don't fire: $(function(){ var $container = $('#container'); $container.imagesLoaded(function(){ $container.masonry({ itemSelector: '.box', }); }); $container.infinitescroll({ navSelector : '#page-nav', nextSelector : '#page-nav a', itemSelector : '.box', loading: { finishedMsg: 'Nothing else to load.', img: 'http://i.imgur.com/6RMhx.gif' } }, function( newElements ) { $.superbox.settings = { closeTxt: "Close this", loadTxt: "Loading your selection", nextTxt: "Next item", prevTxt: "Previous item" }; $.superbox(); var $newElems = $( newElements ).css({ opacity: 0 }); $newElems.imagesLoaded(function(){ $newElems.animate({ opacity: 1 }); $container.masonry( 'appended', $newElems, true ); }); } ); }); I've attempted to combine them so that the 2nd functions are called after .load (after doing some searching on this site and looking at given answers/examples) but nothing seems to work properly. Suggestions?

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  • Link compatibility between C++ and D

    - by Caspin
    D easily interfaces with C. D just as easily interfaces with C++, but (and it's a big but) the C++ needs to be extremely trivial. The code cannot use: namespaces templates multiple inheritance mix virtual with non-virtual methods more? I completely understand the inheritance restriction. The rest however, feel like artificial limitations. Now I don't want to be able to use std::vector<T> directly, but I would really like to be able to link with std::vector<int> as an externed template. The C++ interfacing page has this particularly depressing comment. D templates have little in common with C++ templates, and it is very unlikely that any sort of reasonable method could be found to express C++ templates in a link-compatible way with D. This means that the C++ STL, and C++ Boost, likely will never be accessible from D. Admittedly I'll probably never need std::vector while coding in D, but I'd love to use QT or boost. So what's the deal. Why is it so hard to express non-trivial C++ classes in D? Would it not be worth it to add some special annotations or something to express at least namespaces?

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