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  • Help with bugs in a C code

    - by Yanki Twizzy
    This C code is giving me some unpredictable results. The program is meant to collect 6 nos and print out the max, position of the max no and the average. It's supposed to have only 3 functions - input, max_avr_pos and output for doing what the code is supposed to do but I am getting unpredictable results. Please what could be the problem #include <stdio.h> #include <stdlib.h> #include <conio.h> void input_vals(int arrnum[]); void max_ave_val(int arrnum1[],double *average,int *maxval,int *position); void print_output(double *average1,int *maxval1,int *position1); int main(void) { int arrnum[6],maxval2,position2; double average2; input_vals(arrnum); max_ave_val(arrnum,&average2,&maxval2,&position2); print_output(&average2,&maxval2,&position2); _getche(); return 0; } void input_vals(int arrnum[]) { int count; printf("\n Please enter six numbers\n"); for(count=0;count<6;count++) { scanf("%d",&arrnum[count]); } } void max_ave_val(int arrnum1[],double *average,int *maxval,int *position) { int total=0; int cnt,cnt1,cnt2,limit,maxval2,post; limit=6; /* finding the max value*/ for(cnt=0;cnt<limit-1;cnt++) for(cnt1=limit-1;cnt1>cnt;--cnt1) { if(arrnum1[cnt1-1]>arrnum1[cnt1]) { maxval2=arrnum1[cnt-1]; post=(cnt-1)+1; } else { maxval2=arrnum1[cnt1]; post=cnt1+1; } } *maxval=maxval2; *position=post; /* solving for total */ for(cnt2=0;cnt2<limit;cnt2++); { total=total+arrnum1[cnt2]; } *average=total/limit; } void print_output(double *average1,int *maxval1,int *position1) { printf("\n value of the highest of the numbers is %d\n",*maxval1); printf("\n the average of all the numbers is %g\n",*average1); printf("\n the postion of the highest number in the list is %d\n",*position1); }

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  • Correct usage of socket_select().

    - by Mark Tomlin
    What is the correct way to use socket_select within PHP to send and receive data? I have a connection to the server that allows for both TCP & UDP packet connections, I am utilizing both. Within these connections I'm both sending and receiving packets on the same port, but the TCP packet will be sent on one port (29999) and UDP will be sent on another port (30000). The transmission type will be that of AF_INET. The IP address will be loopback 127.0.0.1. I have many questions on how to create a socket connection within this scenario. For example, is it better to use socket_create_pair to make the connection, or use just socket_create followed by socket_connect, and then implement socket_select? There is a chance that no data will be sent from the server to the client, and it is up to the client to maintain the connection. This will be done by utilizing the time out function within the socket_select call. Should no data be sent within the time limit, the socket_select function will break and a keep alive packet can then be sent. The following script is of the client. // Create $TCP = socket_create(AF_INET, SOCK_STREAM, SOL_TCP); $UDP = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP); // Misc $isAlive = TRUE; $UDPPort = 30000; define('ISP_ISI', 1); // Connect socket_connect($TCP, '127.0.0.1', 29999); socket_connect($UDP, '127.0.0.1', $UDPPort); // Construct Parameters $recv = array($TCP, $UDP); $null = NULL; // Make The Packet to Send. $packet = pack('CCCxSSxCSa16a16', 44, ISP_ISI, 1, $UDPPort, 0, '!', 0, 'AdminPass', 'SocketSelect'); // Send ISI (InSim Init) Packet socket_write($TCP, $packet); /* Main Program Loop */ while ($isAlive == TRUE) { // Socket Select $sock = socket_select($recv, $null, $null, 5); // Check Status if ($sock === FALSE) $isAlive = FALSE; # Error else if ($sock > 0) # How does one check to find what socket changed? else # Something else happed, don't know what as it's not in the documentation, Could this be our timeout getting tripped? }

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  • Ideas on implementing threads and cross process communication. - C

    - by Jamie Keeling
    Hello all! I have an application consisting of two windows, one communicates to the other and sends it a struct constaining two integers (In this case two rolls of a dice). I will be using events for the following circumstances: Process a sends data to process b, process b displays data Process a closes, in turn closing process b Process b closes a, in turn closing process a I have noticed that if the second process is constantly waiting for the first process to send data then the program will be just sat waiting, which is where the idea of implementing threads on each process occured. I have already implemented a thread on the first process which currently creates the data to send to the second process and makes it available to the second process. The problem i'm having is that I don't exactly have a lot of experience with threads and events so I'm not sure of the best way to actually implement what I want to do. Following is a small snippet of what I have so far in the producer application; Rolling the dice and sending the data: case IDM_FILE_ROLLDICE: { hDiceRoll = CreateThread( NULL, // lpThreadAttributes (default) 0, // dwStackSize (default) ThreadFunc(hMainWindow), // lpStartAddress NULL, // lpParameter 0, // dwCreationFlags &hDiceID // lpThreadId (returned by function) ); } break; The data being sent to the other process: DWORD WINAPI ThreadFunc(LPVOID passedHandle) { HANDLE hMainHandle = *((HANDLE*)passedHandle); WCHAR buffer[256]; LPCTSTR pBuf; LPVOID lpMsgBuf; LPVOID lpDisplayBuf; struct diceData storage; HANDLE hMapFile; DWORD dw; //Roll dice and store results in variable storage = RollDice(); hMapFile = CreateFileMapping( (HANDLE)0xFFFFFFFF, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BUF_SIZE, // maximum object size (low-order DWORD) szName); // name of mapping object if (hMapFile == NULL) { dw = GetLastError(); MessageBox(hMainHandle,L"Could not create file mapping object",L"Error",MB_OK); return 1; } pBuf = (LPTSTR) MapViewOfFile(hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BUF_SIZE); if (pBuf == NULL) { MessageBox(hMainHandle,L"Could not map view of file",L"Error",MB_OK); CloseHandle(hMapFile); return 1; } CopyMemory((PVOID)pBuf, &storage, (_tcslen(szMsg) * sizeof(TCHAR))); //_getch(); MessageBox(hMainHandle,L"Completed!",L"Success",MB_OK); UnmapViewOfFile(pBuf); return 0; } I'd like to think I am at least on the right lines, although for some reason when the application finishes creating the thread it hits the return DefWindowProc(hMainWindow, message, wParam, lParam); it crashes saying there's no more source code for the current location. I know there are certain ways to implement things but as I've mentioned I'm not sure if i'm doing this the right way, has anybody else tried to do the same thing? Thanks!

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  • grdb not working variables

    - by stupid_idiot
    hi, i know this is kinda retarded but I just can't figure it out. I'm debugging this: xor eax,eax mov ah,[var1] mov al,[var2] call addition stop: jmp stop var1: db 5 var2: db 6 addition: add ah,al ret the numbers that I find on addresses var1 and var2 are 0x0E and 0x07. I know it's not segmented, but that ain't reason for it to do such escapades, because the addition call works just fine. Could you please explain to me where is my mistake? I see the problem, dunno how to fix it yet though. The thing is, for some reason the instruction pointer starts at 0x100 and all the segment registers at 0x1628. To address the instruction the used combination is i guess [cs:ip] (one of the segment registers and the instruction pointer for sure). The offset to var1 is 0x10 (probably because from the begining of the code it's the 0x10th byte in order), i tried to examine the memory and what i got was: 1628:100 8 bytes 1628:108 8 bytes 1628:110 <- wtf? (assume another 8 bytes) 1628:118 ... whatever tricks are there in the memory [cs:var1] points somewhere else than in my code, which is probably where the label .data would usually address ds.... probably.. i don't know what is supposed to be at 1628:10 ok, i found out what caused the assness and wasted me whole fuckin day. the behaviour described above is just correct, the code is fully functional. what i didn't know is that grdb debugger for some reason sets the begining address to 0x100... the sollution is to insert the directive ORG 0x100 on the first line and that's the whole thing. the code was working because instruction pointer has the right address to first instruction and goes one by one, but your assembler doesn't know what effective address will be your program stored at so it pretty much remains relative to first line of the code which means all the variables (if not using label for data section) will remain pointing as if it started at 0x0. which of course wouldn't work with DOS. and grdb apparently emulates some DOS features... sry for the language, thx everyone for effort, hope this will spare someone's time if having the same problem... heheh.. at least now i know the reason why to use .data section :))))

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  • bad file descriptor with close() socket (c++)

    - by user321246
    hi everybody! I'm running out of file descriptors when my program can't connect another host. The close() system call doesn't work, the number of open sockets increases. I can se it with cat /proc/sys/fs/file-nr Print from console: connect: No route to host close: Bad file descriptor connect: No route to host close: Bad file descriptor .. Code: #include <stdio.h> #include <stdlib.h> #include <sys/socket.h> #include <netinet/in.h> #include <netdb.h> #include <string.h> #include <iostream> using namespace std; #define PORT 1238 #define MESSAGE "Yow!!! Are we having fun yet?!?" #define SERVERHOST "192.168.9.101" void write_to_server (int filedes) { int nbytes; nbytes = write (filedes, MESSAGE, strlen (MESSAGE) + 1); if (nbytes < 0) { perror ("write"); } } void init_sockaddr (struct sockaddr_in *name, const char *hostname, uint16_t port) { struct hostent *hostinfo; name->sin_family = AF_INET; name->sin_port = htons (port); hostinfo = gethostbyname (hostname); if (hostinfo == NULL) { fprintf (stderr, "Unknown host %s.\n", hostname); } name->sin_addr = *(struct in_addr *) hostinfo->h_addr; } int main() { for (;;) { sleep(1); int sock; struct sockaddr_in servername; /* Create the socket. */ sock = socket (PF_INET, SOCK_STREAM, 0); if (sock < 0) { perror ("socket (client)"); } /* Connect to the server. */ init_sockaddr (&servername, SERVERHOST, PORT); if (0 > connect (sock, (struct sockaddr *) &servername, sizeof (servername))) { perror ("connect"); sock = -1; } /* Send data to the server. */ if (sock > -1) write_to_server (sock); if (close (sock) != 0) perror("close"); } return 0; }

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  • Read from file in eclipse

    - by Buzkie
    I'm trying to read from a text file to input data to my java program. However, eclipse continuosly gives me a Source not found error no matter where I put the file. I've made an additional sources folder in the project directory, the file in question is in both it and the bin file for the project and it still can't find it. I even put a copy of it on my desktop and tried pointing eclipse there when it asked me to browse for the source lookup path. No matter what I do it can't find the file. here's my code in case it's pertinent: System.out.println(System.getProperty("user.dir")); File file = new File("file.txt"); Scanner scanner = new Scanner(file); in addition, it says the user directory is the project directory and there is a copy there too. I have no clue what to do. Thanks, Alex after attempting the suggestion below and refreshing again, I was greeted by a host of errors. FileNotFoundException(Throwable).<init>(String) line: 195 FileNotFoundException(Exception).<init>(String) line: not available FileNotFoundException(IOException).<init>(String) line: not available FileNotFoundException.<init>(String) line: not available URLClassPath$JarLoader.getJarFile(URL) line: not available URLClassPath$JarLoader.access$600(URLClassPath$JarLoader, URL) line: not available URLClassPath$JarLoader$1.run() line: not available AccessController.doPrivileged(PrivilegedExceptionAction<T>) line: not available [native method] URLClassPath$JarLoader.ensureOpen() line: not available URLClassPath$JarLoader.<init>(URL, URLStreamHandler, HashMap) line: not available URLClassPath$3.run() line: not available AccessController.doPrivileged(PrivilegedExceptionAction<T>) line: not available [native method] URLClassPath.getLoader(URL) line: not available URLClassPath.getLoader(int) line: not available URLClassPath.access$000(URLClassPath, int) line: not available URLClassPath$2.next() line: not available URLClassPath$2.hasMoreElements() line: not available ClassLoader$2.hasMoreElements() line: not available CompoundEnumeration<E>.next() line: not available CompoundEnumeration<E>.hasMoreElements() line: not available ServiceLoader$LazyIterator.hasNext() line: not available ServiceLoader$1.hasNext() line: not available LocaleServiceProviderPool$1.run() line: not available AccessController.doPrivileged(PrivilegedExceptionAction<T>) line: not available [native method] LocaleServiceProviderPool.<init>(Class<LocaleServiceProvider>) line: not available LocaleServiceProviderPool.getPool(Class<LocaleServiceProvider>) line: not available NumberFormat.getInstance(Locale, int) line: not available NumberFormat.getNumberInstance(Locale) line: not available Scanner.useLocale(Locale) line: not available Scanner.<init>(Readable, Pattern) line: not available Scanner.<init>(ReadableByteChannel) line: not available Scanner.<init>(File) line: not available code used: System.out.println(System.getProperty("user.dir")); File file = new File(System.getProperty("user.dir") + "/file.txt"); Scanner scanner = new Scanner(file);

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  • Delphi - Read File To StringList, then delete and write back to file.

    - by Jkraw90
    I'm currently working on a program to generate the hashes of files, in Delphi 2010. As part of this I have a option to create User Presets, e.g. pre-defined choice of hashing algo's which the user can create/save/delete. I have the create and load code working fine. It uses a ComboBox and loads from a file "fhpre.ini", inside this file is the users presets stored in format of:- PresetName PresetCode (a 12 digit string using 0 for don't hash and 1 for do) On application loading it loads the data from this file into the ComboBox and an Array with the ItemIndex of ComboBox matching the corrisponding correct string of 0's and 1's in the Array. Now I need to implement a feature to have the user delete a preset from the list. So far my code is as follows, procedure TForm1.Panel23Click(Sender : TObject); var fil : textfile; contents : TStringList; x,i : integer; filline : ansistring; filestream : TFileStream; begin //Start Procedure //Load data into StringList contents := TStringList.Create; fileStream := TFileStream.Create((GetAppData+'\RFA\fhpre.ini'), fmShareDenyNone); Contents.LoadFromStream(fileStream); fileStream.Destroy(); //Search for relevant Preset i := 0; if ComboBox4.Text <> Contents[i] then begin Repeat i := i + 1; Until ComboBox4.Text = Contents[i]; end; contents.Delete(i); //Delete Relevant Preset Name contents.Delete(i); //Delete Preset Digit String //Write StringList back to file. AssignFile(fil,(GetAppData+'\RFA\fhpre.ini')); ReWrite(fil); for i := 0 to Contents.Count -1 do WriteLn(Contents[i]); CloseFile(fil); Contents.Free; end; However if this is run, I get a 105 error when it gets to the WriteLn section. I'm aware that the code isn't great, for example doesn't have checks for presets with same name, but that will come, I want to get the base code working first then can tweak and add extra checks etc. Any help would be appreciated.

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  • SQL Invalid Object Name 'AddressType'

    - by salvationishere
    I am getting the above error in my VS 2008 C# method when I try to invoke the SQL getColumnNames stored procedure from VS. This SP accepts one input parameter, the table name, and works successfully from SSMS. Currently I am selecting the AdventureWorks AddressType table for it to pull the column names from this table. I can see teh AdventureWorks table available in VS from my Server Explorer / Data Connection. And I see both the AddressType table and getColumnNames SP showing in Server Explorer. But I am still getting this error listed above. Here is the C# code snippet I use to execute this: public static DataTable DisplayTableColumns(string tt) { SqlDataReader dr = null; string TableName = tt; string connString = "Data Source=.;AttachDbFilename=\"C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\AdventureWorks_Data.mdf\";Initial Catalog=AdventureWorks;Integrated Security=True;Connect Timeout=30;User Instance=False"; string errorMsg; SqlConnection conn2 = new SqlConnection(connString); SqlCommand cmd = conn2.CreateCommand(); try { cmd.CommandText = "dbo.getColumnNames"; cmd.CommandType = CommandType.StoredProcedure; cmd.Connection = conn2; SqlParameter parm = new SqlParameter("@TableName", SqlDbType.VarChar); parm.Value = TableName; parm.Direction = ParameterDirection.Input; cmd.Parameters.Add(parm); conn2.Open(); dr = cmd.ExecuteReader(); } catch (Exception ex) { errorMsg = ex.Message; } And when I examine the errorMsg it says the following: " at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)\r\n at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)\r\n at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)\r\n at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)\r\n at System.Data.SqlClient.SqlDataReader.ConsumeMetaData()\r\n at System.Data.SqlClient.SqlDataReader.get_MetaData()\r\n at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString)\r\n at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async)\r\n at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)\r\n at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)\r\n at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)\r\n at System.Data.SqlClient.SqlCommand.ExecuteReader()\r\n at ADONET_namespace.ADONET_methods.DisplayTableColumns(String tt) in C:\Documents and Settings\Admin\My Documents\Visual Studio 2008\Projects\AddFileToSQL\AddFileToSQL\ADONET methods.cs:line 35" Where line 35 is dr = cmd.ExecuteReader();

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  • C++ DLL creation for C# project - No functions exported

    - by Yeti
    I am working on a project that requires some image processing. The front end of the program is C# (cause the guys thought it is a lot simpler to make the UI in it). However, as the image processing part needs a lot of CPU juice I am making this part in C++. The idea is to link it to the C# project and just call a function from a DLL to make the image processing part and allow to the C# environment to process the data afterwards. Now the only problem is that it seems I am not able to make the DLL. Simply put the compiler refuses to put any function into the DLL that I compile. Because the project requires some development time testing I have created two projects into a C++ solution. One is for the Dll and another console application. The console project holds all the files and I just include the corresponding header into my DLL project file. I thought the compiler should take out the functions that I marked as to be exported and make the DLL from them. Nevertheless this does not happens. Here it is how I defined the function in the header: extern "C" __declspec(dllexport) void _stdcall RobotData(BYTE* buf, int** pToNewBackgroundImage, int* pToBackgroundImage, bool InitFlag, ObjectInformation* robot1, ObjectInformation* robot2, ObjectInformation* robot3, ObjectInformation* robot4, ObjectInformation* puck); extern "C" __declspec(dllexport) CvPoint _stdcall RefPointFinder(IplImage* imgInput, CvRect &imgROI, CvScalar &refHSVColorLow, CvScalar &refHSVColorHi ); Followed by the implementation in the cpp file: extern "C" __declspec(dllexport) CvPoint _stdcall RefPointFinder(IplImage* imgInput, CvRect &imgROI,&refHSVColorLow, CvScalar &refHSVColorHi ) { \\... return cvPoint((int)( M10/M00) + imgROI.x, (int)( M01/M00 ) + imgROI.y) ;} extern "C" __declspec(dllexport) void _stdcall RobotData(BYTE* buf, int** pToNewBackgroundImage, int* pToBackgroundImage, bool InitFlag, ObjectInformation* robot1, ObjectInformation* robot2, ObjectInformation* robot3, ObjectInformation* robot4, ObjectInformation* puck) { \\ ...}; And my main file for the DLL project looks like: #ifdef _MANAGED #pragma managed(push, off) #endif /// <summary> Include files. </summary> #include "..\ImageProcessingDebug\ImageProcessingTest.h" #include "..\ImageProcessingDebug\ImageProcessing.h" BOOL APIENTRY DllMain( HMODULE hModule, DWORD ul_reason_for_call, LPVOID lpReserved) { return TRUE; } #ifdef _MANAGED #pragma managed(pop) #endif Needless to say it does not work. A quick look with DLL export viewer 1.36 reveals that no function is inside the library. I don't get it. What I am doing wrong ? As side not I am using the C++ objects (and here it is the C++ DLL part) such as the vector. However, only for internal usage. These will not appear in the headers of either function as you can observe from the previous code snippets. Any ideas? Thx, Bernat

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  • urgent..haskell mini interpreter

    - by mohamed elshikh
    i'm asked to implement this project and i have problems in part b which is the eval function this is the full describtion of the project You are required to implement an interpreter for mini-Haskell language. An interpreter is dened in Wikipedia as a computer program that executes, i.e. performs, instructions written in a programming language. The interpreter should be able to evaluate functions written in a special notation, which you will dene. A function is dened by: Function name Input Parameters : dened as a list of variables. The body of the function. The body of the function can be any of the following statements: a) Variable: The function may return any of the input variables. b) Arithmetic Expressions: The arithmetic expressions include input variables and addition, sub- traction, multiplication, division and modulus operations on arithmetic expressions. c) Boolean Expressions: The Boolean expressions include the ordering of arithmetic expressions (applying the relationships: <, =<, , = or =) and the anding, oring and negation of Boolean expressions. d) If-then-else statements: where the if keyword is followed by a Boolean expression. The then and else parts may be followed by any of the statements described here. e) Guarded expressions: where each case consists of a boolean expression and any of the statements described here. The expression consists of any number of cases. The rst case whose condition is true, its body should be evaluated. The guarded expression has to terminate with an otherwise case. f) Function calls: the body of the function may have a call to another function. Note that all inputs passed to the function will be of type Int. The output of the function can be of type Int or Bool. To implement the interpreter, you are required to implement the following: a) Dene a datatype for the following expressions: Variables Arithmetic expressions Boolean expressions If-then-else statements Guarded expressions Functions b) Implement the function eval which evaluates a function. It takes 3 inputs: The name of a function to be evaluated represented as a string. A list of inputs to that function. The arguments will always be of datatype Int. A list of functions. Each function is represented as instance of the datatype that you have created for functions. c) Implement the function get_type that returns the type of the function (as a string). The input to this function is the same as in part b. here is what i've done data Variable = v(char) data Arth= va Variable | Add Arth Arth | Sub Arth Arth | Times Arth Arth | Divide Arth Arth data Bol= Great Arth Arth | Small Arth Arth | Geq Arth Arth | Seq Arth Arth | And Bol Bol | Or Bol Bol | Neg Bol data Cond = data Guard = data Fun =cons String [Variable] Body data Body= bodycons(String) |Bol |Cond |Guard |Arth

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  • howto parse struct to C++ dll from C#

    - by Nerds Rule
    I am trying to call a function in a unmanaged C++ dll. It has this prototype: [DllImport("C:\\Program Files\\MySDK\\VSeries.dll", EntryPoint = "BII_Send_Index_Template_MT" )] internal unsafe static extern Int32 BII_Send_Index_Template_MT(IntPtr pUnitHandle, ref BII_Template template, Int32 option, Boolean async); BII_Template template = new BII_Template(); error_code = BII_Send_Index_Template_MT(pUnitHandle, ref template, option, false); I is how I define the BII_Template struct in C#: public unsafe struct BII_Template { public ulong id; public ulong employee_id; public ulong password; public byte sensor_version; public byte template_version; public fixed char name[16]; public byte finger; public byte admin_level; public byte schedule; public byte security_thresh; public fixed byte noise_level[18]; public byte corramb; public byte reference_x; public byte reference_y; public fixed byte ihcore[3]; public fixed byte ivcore[3]; public byte temp_xoffset; public byte temp_yoffset; public byte index; public fixed byte inphase[5500]; }; It build and when I run it the dll return error_code = "The record checksum is invalid." I assume that I am using the ref keyword in a wrong way or the size of some of the elements in the struct is wrong. ----- EDIT ------------ Here is the struct in C++: typedef struct { unsigned long id; unsigned long employee_id; unsigned long password; unsigned char sensor_version; unsigned char template_version; char name[16]; unsigned char finger; unsigned char admin_level; unsigned char schedule; unsigned char security_thresh; unsigned char noise_level[18]; unsigned char corramb ; unsigned char reference_x ; unsigned char reference_y ; unsigned char ihcore[NUM_CORE]; unsigned char ivcore[NUM_CORE]; unsigned char temp_xoffset; unsigned char temp_yoffset; unsigned char index; unsigned char inphase[PACKED_ARRAY_SIZE]; } BII_Template;

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  • OpenGL Coordinate system confusion

    - by user146780
    Maybe I set up GLUT wrong. Basically I want verticies to be reletive to their size in pixels. Ex:right now if I create a hexagon, it hakes up the whole screen even though the units are 6. #include <iostream> #include <stdlib.h> //Needed for "exit" function #include <cmath> //Include OpenGL header files, so that we can use OpenGL #ifdef __APPLE__ #include <OpenGL/OpenGL.h> #include <GLUT/glut.h> #else #include <GL/glut.h> #endif using namespace std; //Called when a key is pressed void handleKeypress(unsigned char key, //The key that was pressed int x, int y) { //The current mouse coordinates switch (key) { case 27: //Escape key exit(0); //Exit the program } } //Initializes 3D rendering void initRendering() { //Makes 3D drawing work when something is in front of something else glEnable(GL_DEPTH_TEST); } //Called when the window is resized void handleResize(int w, int h) { //Tell OpenGL how to convert from coordinates to pixel values glViewport(0, 0, w, h); glMatrixMode(GL_PROJECTION); //Switch to setting the camera perspective //Set the camera perspective glLoadIdentity(); //Reset the camera gluPerspective(45.0, //The camera angle (double)w / (double)h, //The width-to-height ratio 1.0, //The near z clipping coordinate 200.0); //The far z clipping coordinate } //Draws the 3D scene void drawScene() { //Clear information from last draw glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); //Reset the drawing perspective glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); glBegin(GL_POLYGON); //Begin quadrilateral coordinates //Trapezoid glColor3f(255,0,0); for(int i = 0; i < 6; ++i) { glVertex2d(sin(i/6.0*2* 3.1415), cos(i/6.0*2* 3.1415)); } glEnd(); //End quadrilateral coordinates glutSwapBuffers(); //Send the 3D scene to the screen } int main(int argc, char** argv) { //Initialize GLUT glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH); glutInitWindowSize(400, 400); //Set the window size //Create the window glutCreateWindow("Basic Shapes - videotutorialsrock.com"); initRendering(); //Initialize rendering //Set handler functions for drawing, keypresses, and window resizes glutDisplayFunc(drawScene); glutKeyboardFunc(handleKeypress); glutReshapeFunc(handleResize); glutMainLoop(); //Start the main loop. glutMainLoop doesn't return. return 0; //This line is never reached } How can I make it so that a polygon of 0,0 10,0 10,10 0,10 defines a polygon starting at the top left of the screen and is a width and height of 10 pixels? Thanks

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  • Two loops speeds drawing in a Jframe

    - by noahn567
    I have a program that requires two classes. The player-Names class, and the Player-Model class. I want the player-Names class to repaint every half second, and the Player-Model class to repaint 60 times per second because i want the movement to be smooth. The problem that i am having is that i want all of this to be done on one J-frame. How would i go about doing this? If you could lead me in the right direction or give me a little example that would be great! Thank you :). for some reason it wont let me post so i'm going to put in some random code import java.awt.Color; import java.awt.Font; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import javax.swing.JComponent; import javax.swing.JFrame; public class PlayerNames extends JFrame { static int connectionTimer = 0; static int connectionTimer2 = 0; static int reconnect = 0; static int reconnectValue = 1; static int x = 0; static int reconnectWait = connectionTimer + reconnectValue; private static final long serialVersionUID = 1L; public graph gg = new graph(); public graph g = new graph(); private static GameClient socketClient; private GameServer socketServer; public static void main(int width, int height) { PlayerNames tt = new PlayerNames(); // PlayerGraphics t = new PlayerGraphics(); tt.setSize(width, height); if (Game.ServerOwner == 1) { tt.setTitle("Server: " + Game.username); } else { tt.setTitle("Username: " + Game.username); } tt.setVisible(true); tt.getContentPane().add(tt.gg); tt.getContentPane().add(tt.g); tt.setDefaultCloseOperation(EXIT_ON_CLOSE); tt.setResizable(false); }

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  • Unable to read data from the transport connection: the connection was closed

    - by webdreamer
    The exception is Remoting Exception - Authentication Failure. The detailed message says "Unable to read data from the transport connection: the connection was closed." I'm having trouble with creating two simple servers that can comunicate as remote objects in C#. ServerInfo is just a class I created that holds the IP and Port and can give back the address. It works fine, as I used it before, and I've debugged it. Also the server is starting just fine, no exception is thrown, and the channel is registered without problems. I'm using Forms to do the interfaces, and call some of the methods on the server, but didn't find any problems in passing the parameters from the FormsApplication to the server when debugging. All seems fine in that chapter. public ChordServerProgram() { RemotingServices.Marshal(this, "PADIBook"); nodeInt = 0; } public void startServer() { try { serverChannel = new TcpChannel(serverInfo.Port); ChannelServices.RegisterChannel(serverChannel, true); } catch (Exception e) { Console.WriteLine(e.ToString()); } } I run two instances of this program. Then startNode is called on one of the instances of the application. The port is fine, the address generated is fine as well. As you can see, I'm using the IP for localhost, since this server is just for testing purposes. public void startNode(String portStr) { IPAddress address = IPAddress.Parse("127.0.0.1"); Int32 port = Int32.Parse(portStr); serverInfo = new ServerInfo(address, port); startServer(); //node = new ChordNode(serverInfo,this); } Then, in the other istance, through the interface again, I call another startNode method, giving it a seed server to get information from. This is where it goes wrong. When it calls the method on the seedServer proxy it just got, a RemotingException is thrown, due to an authentication failure. (The parameter I'll want to get is the node, I'm just using the int to make sure the ChordNode class has nothing to do with this error.) public void startNode(String portStr, String seedStr) { IPAddress address = IPAddress.Parse("127.0.0.1"); Int32 port = Int32.Parse(portStr); serverInfo = new ServerInfo(address, port); IPAddress addressSeed = IPAddress.Parse("127.0.0.1"); Int32 portSeed = Int32.Parse(seedStr); ServerInfo seedInfo = new ServerInfo(addressSeed, portSeed); startServer(); ChordServerProgram seedServer = (ChordServerProgram)Activator.GetObject(typeof(ChordServerProgram), seedInfo.GetFullAddress()); // node = new ChordNode(serverInfo,this); int seedNode = seedServer.nodeInt; // node.chordJoin(seedNode.self); }

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  • Is it Bad Practice to use C++ only for the STL containers?

    - by gmatt
    First a little background ... In what follows, I use C,C++ and Java for coding (general) algorithms, not gui's and fancy program's with interfaces, but simple command line algorithms and libraries. I started out learning about programming in Java. I got pretty good with Java and I learned to use the Java containers a lot as they tend to reduce complexity of book keeping while guaranteeing great performance. I intermittently used C++, but I was definitely not as good with it as with Java and it felt cumbersome. I did not know C++ enough to work in it without having to look up every single function and so I quickly reverted back to sticking to Java as much as possible. I then made a sudden transition into cracking and hacking in assembly language, because I felt I was concentrated too much attention on a much too high level language and I needed more experience with how a CPU interacts with memory and whats really going on with the 1's and 0's. I have to admit this was one of the most educational and fun experiences I've had with computers to date. For obviously reasons, I could not use assembly language to code on a daily basis, it was mostly reserved for fun diversions. After learning more about the computer through this experience I then realized that C++ is so much closer to the "level of 1's and 0's" than Java was, but I still felt it to be incredibly obtuse, like a swiss army knife with far too many gizmos to do any one task with elegance. I decided to give plain vanilla C a try, and I quickly fell in love. It was a happy medium between simplicity and enough "micromanagent" to not abstract what is really going on. However, I did miss one thing about Java: the containers. In particular, a simple container (like the stl vector) that expands dynamically in size is incredibly useful, but quite a pain to have to implement in C every time. Hence my code currently looks like almost entirely C with containers from C++ thrown in, the only feature I use from C++. I'd like to know if its consider okay in practice to use just one feature of C++, and ignore the rest in favor of C type code?

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  • What makes a Winform position initially stale?

    - by msorens
    The code below demonstrates a very simple problem; I am hoping that I am just missing a setting that someone might be able to reveal. Goal (1) Launch main winform (MainForm). (2) Press button to display secondary winform (ShadowForm) that is semi-transparent and should exactly overlay MainForm. What Actually Happens Scenario 1: Launch main winform then press button: ShadowForm displays with correct size but incorrect location, lower and to the right (as if it was cascaded). Press button to close ShadowForm again. Press button once more to reopen ShadowForm and now it is in the correct position, covering MainForm. Scenario 2: Launch main winform, move it around, then press button: ShadowForm displays with correct size but incorrect location (where the MainForm was before moving it). Press button to close; press again to reopen and now ShadowForm is in the correct position. using System; using System.Windows.Forms; namespace LocationTest { static class Program { static void Main() { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); Application.Run(new MainForm()); } } public class MainForm : Form { ShadowForm shadowForm = new ShadowForm(); Button button1 = new Button(); System.ComponentModel.IContainer components = null; public MainForm() { this.SuspendLayout(); this.button1.Location = new System.Drawing.Point(102, 44); this.button1.Size = new System.Drawing.Size(75, 23); this.button1.Text = "button1"; this.button1.Click += new System.EventHandler(this.button1_Click); this.ClientSize = new System.Drawing.Size(292, 266); this.Controls.Add(this.button1); this.ResumeLayout(false); } private void button1_Click(object sender, EventArgs e) { if (shadowForm.Visible) { shadowForm.Hide(); } else { shadowForm.Size = Size; // this always works shadowForm.Location = Location; // this fails first time, but works second time! shadowForm.Show(); } } protected override void Dispose(bool disposing) { if (disposing && (components != null)) { components.Dispose(); } base.Dispose(disposing); } } public class ShadowForm : Form { private System.ComponentModel.IContainer components = null; public ShadowForm() { this.SuspendLayout(); this.BackColor = System.Drawing.Color.Black; this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None; this.Opacity = 0.5; this.Click += new System.EventHandler(this.ShadowForm_Click); this.ResumeLayout(false); } private void ShadowForm_Click(object sender, EventArgs e) { Hide(); } protected override void Dispose(bool disposing) { if (disposing && (components != null)) { components.Dispose(); } base.Dispose(disposing); } } }

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  • plane bombing problems- help

    - by peiska
    I'm training code problems, and on this one I am having problems to solve it, can you give me some tips how to solve it please. The problem is something like this: Your task is to find the sequence of points on the map that the bomber is expected to travel such that it hits all vital links. A link from A to B is vital when its absence isolates completely A from B. In other words, the only way to go from A to B (or vice versa) is via that link. Notice that if we destroy for example link (d,e), it becomes impossible to go from d to e,m,l or n in any way. A vital link can be hit at any point that lies in its segment (e.g. a hit close to d is as valid as a hit close to e). Of course, only one hit is enough to neutralize a vital link. Moreover, each bomb affects an exact circle of radius R, i.e., every segment that intersects that circle is considered hit. Due to enemy counter-attack, the plane may have to retreat at any moment, so the plane should follow, at each moment, to the closest vital link possible, even if in the end the total distance grows larger. Given all coordinates (the initial position of the plane and the nodes in the map) and the range R, you have to determine the sequence of positions in which the plane has to drop bombs. This sequence should start (takeoff) and finish (landing) at the initial position. Except for the start and finish, all the other positions have to fall exactly in a segment of the map (i.e. it should correspond to a point in a non-hit vital link segment). The coordinate system used will be UTM (Universal Transverse Mercator) northing and easting, which basically corresponds to a Euclidian perspective of the world (X=Easting; Y=Northing). Input Each input file will start with three floating point numbers indicating the X0 and Y0 coordinates of the airport and the range R. The second line contains an integer, N, indicating the number of nodes in the road network graph. Then, the next N (<10000) lines will each contain a pair of floating point numbers indicating the Xi and Yi coordinates (1 No two links will ever cross with each other. Output The program will print the sequence of coordinates (pairs of floating point numbers with exactly one decimal place), each one at a line, in the order that the plane should visit (starting and ending in the airport). Sample input 1 102.3 553.9 0.2 14 342.2 832.5 596.2 638.5 479.7 991.3 720.4 874.8 744.3 1284.1 1294.6 924.2 1467.5 659.6 1802.6 659.6 1686.2 860.7 1548.6 1111.2 1834.4 1054.8 564.4 1442.8 850.1 1460.5 1294.6 1485.1 17 1 2 1 3 2 4 3 4 4 5 4 6 6 7 7 8 8 9 8 10 9 10 10 11 6 11 5 12 5 13 12 13 13 14 Sample output 1 102.3 553.9 720.4 874.8 850.1 1460.5 102.3 553.9

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  • Displaying xaml resources dynamically?

    - by Robert
    I used Mike Swanson's illustrator to xaml converter to convert some of my images to xaml. The convert creates a viewbox that contains the image. These viewboxes I made resource files in my program. The code below shows what I'm trying to do: I have a viewmodel that has an enum variable called PrimaryWinding of type Windings. The values PrimD and PrimY of the enum select the respective PrimD and PrimY xaml files in the resources. <UserControl.Resources> <DataTemplate x:Key="PrimTrafo" DataType="{x:Type l:Windings}"> <Frame Source="{Binding}" x:Name="PART_Image" NavigationUIVisibility="Hidden"> <Frame.LayoutTransform> <ScaleTransform ScaleX="0.5" ScaleY="0.5"/> </Frame.LayoutTransform> </Frame> <DataTemplate.Triggers> <DataTrigger Binding="{Binding}" Value="PrimD"> <Setter TargetName="PART_Image" Property="Source" Value="Resources\PrimD.xaml" /> </DataTrigger> <DataTrigger Binding="{Binding}" Value="PrimY"> <Setter TargetName="PART_Image" Property="Source" Value="Resources\PrimY.xaml" /> </DataTrigger> </DataTemplate.Triggers> </DataTemplate> </UserControl.Resources> <!--The contentcontrol that holds the datatemplate defined above--> <Grid > <Grid.ColumnDefinitions> <ColumnDefinition Width="2*"></ColumnDefinition> <ColumnDefinition Width="2*"></ColumnDefinition> <ColumnDefinition Width="1*"></ColumnDefinition> </Grid.ColumnDefinitions> <ContentControl Grid.Column="0" Content="{Binding PrimaryWinding}" ContentTemplate="{StaticResource PrimTrafo}"/> </Grid> This code works. Only I can't resize the drawings to the size of the grid cell. I added the ScaleTransform class to resize the image. Is a Frame the wrong class to hold the drawings? Should I use the ScaleTransform class to resize the drawing to the size of the cell? And how can I do that dynamically?

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  • Rewriting Live TCP/IP (Layer 4) (i.e. Socket Layer) Streams

    - by user213060
    I have a simple problem which I'm sure someone here has done before... I want to rewrite Layer 4 TCP/IP streams (Not lower layer individual packets or frames.) Ettercap's etterfilter command lets you perform simple live replacements of Layer 4 TCP/IP streams based on fixed strings or regexes. Example ettercap scripting code: if (ip.proto == TCP && tcp.dst == 80) { if (search(DATA.data, "gzip")) { replace("gzip", " "); msg("whited out gzip\n"); } } if (ip.proto == TCP && tcp.dst == 80) { if (search(DATA.data, "deflate")) { replace("deflate", " "); msg("whited out deflate\n"); } } http://ettercap.sourceforge.net/forum/viewtopic.php?t=2833 I would like to rewrite streams based on my own filter program instead of just simple string replacements. Anyone have an idea of how to do this? Is there anything other than Ettercap that can do live replacement like this, maybe as a plugin to a VPN software or something? I would like to have a configuration similar to ettercap's silent bridged sniffing configuration between two Ethernet interfaces. This way I can silently filter traffic coming from either direction with no NATing problems. Note that my filter is an application that acts as a pipe filter, similar to the design of unix command-line filters: >[eth0] <----------> [my filter] <----------> [eth1]< What I am already aware of, but are not suitable: Tun/Tap - Works at the lower packet layer, I need to work with the higher layer streams. Ettercap - I can't find any way to do replacements other than the restricted capabilities in the example above. Hooking into some VPN software? - I just can't figure out which or exactly how. libnetfilter_queue - Works with lower layer packets, not TCP/IP streams. Again, the rewriting should occur at the transport layer (Layer 4) as it does in this example, instead of a lower layer packet-based approach. Exact code will help immensely! Thanks!

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  • A case-insensitive related implementation problem

    - by Robert
    Hi All, I am going through a final refinement posted by the client, which needs me to do a case-insesitive query. I will basically walk through how this simple program works. First of all, in my Java class, I did a fairly simple webpage parsing: title=(String)results.get("title"); doc = docBuilder.parse("http://" + server + ":" + port + "/exist/rest/db/wb/xql/media_lookup.xql?" + "&title=" + title); This Java statement references an XQuery file "media_lookup.xql" which is stored on localhost, and the only parameter we are passing is the string "title". Secondly, let's take at look at that XQuery file: $title := request:get-parameter('title',""), $mediaNodes := doc('/db/wb/portfolio/media_data.xml'), $query := $mediaNodes//media[contains(title,$title)], Then it will evaluate that query. This XQuery will get the "title" parameter that are passes from our Java class, and query the "media_data" xml file stored in the database, which contains a bunch of media nodes with a 'title' element node. As you may expect, this simple query will just match those media nodes whose 'title' element contains a substring of what the value of string 'title' is. So if our 'title' is "Chi", it will return media nodes whose title may be "Chicago" or "Chicken". The refinment request posted by the client is that there should be NO case-sensitivity. The very intuitive way is to modify the XQuery statement by using a lower-case funtion in it, like: $query := $mediaNodes//media[contains(lower-case(title/text(),lower-case($title))], However, the question comes: this modified query will run my machine into memory overflow. Since my "media_data.xml" is quite huge and contains thouands of millions of media nodes, I assume the lower-case() function will run on each of the entries, thus causing the machine to crash. I've talked with some experienced XQuery programmer, and they think I should use an index to solve this problem, and I will definitely research into that. But before that, I am just posting this problem here to get other ideas or any suggestions, do you think any other way may help? for example, could I tweak the Java parse statement to realize the case-insensitivity? Since I think I saw some people did some string concatination by using "contains." in Java before passing it to the server. Any idea or help is welcomed, thanks in advance.

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  • C++ include statement required if defining a map in a headerfile.

    - by Justin
    I was doing a project for computer course on programming concepts. This project was to be completed in C++ using Object Oriented designs we learned throughout the course. Anyhow, I have two files symboltable.h and symboltable.cpp. I want to use a map as the data structure so I define it in the private section of the header file. I #include <map> in the cpp file before I #include "symboltable.h". I get several errors from the compiler (MS VS 2008 Pro) when I go to debug/run the program the first of which is: Error 1 error C2146: syntax error : missing ';' before identifier 'table' c:\users\jsmith\documents\visual studio 2008\projects\project2\project2\symboltable.h 22 Project2 To fix this I had to #include <map> in the header file, which to me seems strange. Here are the relevant code files: // symboltable.h #include <map> class SymbolTable { public: SymbolTable() {} void insert(string variable, double value); double lookUp(string variable); void init(); // Added as part of the spec given in the conference area. private: map<string, double> table; // Our container for variables and their values. }; and // symboltable.cpp #include <map> #include <string> #include <iostream> using namespace std; #include "symboltable.h" void SymbolTable::insert(string variable, double value) { table[variable] = value; // Creates a new map entry, if variable name already exist it overwrites last value. } double SymbolTable::lookUp(string variable) { if(table.find(variable) == table.end()) // Search for the variable, find() returns a position, if thats the end then we didnt find it. throw exception("Error: Uninitialized variable"); else return table[variable]; } void SymbolTable::init() { table.clear(); // Clears the map, removes all elements. }

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  • Configuring a html page from an original demo page

    - by Wold
    I forked into rainyday.js through github, an awesome javascript program made by maroslaw at this link: https://github.com/maroslaw/rainyday.js. Basically I tried taking his demo page and my own photo city.jpg and changed the applicable fields so that I could run it on my own site, but only the picture loads and the script itself doesn't start to run. I'm pretty new to html and javascript so I'm probably omitting something very simple, but here is the script for the demo code: <script src="rainyday.js"></script> <script> function getURLParameter(name) { return decodeURIComponent((new RegExp('[?|&]' + name + '=' + '([^&;]+?)(&|#|;|$)').exec(location.search)||[,''])[1].replace(/\+/g, '%20'))||null; } function demo() { var image = document.getElementById('background'); image.onload = function () { var engine = null; var preset = getURLParameter('preset') || '1'; if (preset === '1') { engine = new RainyDay({ element: 'background', blur: 10, opacity: 1, fps: 30, speed: 30 }); engine.rain([ [1, 2, 8000] ]); engine.rain([ [3, 3, 0.88], [5, 5, 0.9], [6, 2, 1] ], 100); } else if (preset === '2') { engine = new RainyDay({ element: 'background', blur: 10, opacity: 1, fps: 30, speed: 30 }); engine.VARIABLE_GRAVITY_ANGLE = Math.PI / 8; engine.rain([ [0, 2, 0.5], [4, 4, 1] ], 50); } else if (preset === '3') { engine = new RainyDay({ element: 'background', blur: 10, opacity: 1, fps: 30, speed: 30 }); engine.trail = engine.TRAIL_SMUDGE; engine.rain([ [0, 2, 0.5], [4, 4, 1] ], 100); } }; image.crossOrigin = 'anonymous'; if (getURLParameter('imgur')) { image.src = 'http://i.imgur.com/' + getURLParameter('imgur') + '.jpg'; } else if (getURLParameter('img')) { image.src = getURLParameter('img') + '.jpg'; } var youtube = getURLParameter('youtube'); if (youtube) { var div = document.getElementById('sound'); var player = document.createElement('iframe'); player.frameborder = '0'; player.height = '1'; player.width = '1'; player.src = 'https://youtube.com/embed/' + youtube + '?autoplay=1&controls=0&showinfo=0&autohide=1&loop=1'; div.appendChild(player); } } </script> This is where I am naming my background and specifying the photo from within the directory. <body onload="demo();"> <div id="sound" style="z-index: -1;"></div> <div id="parent"> <img id='background' alt="background" src="city.jpg" /> </div> </body> The actual code for the whole entire rainyday.js script can be found here: https://github.com/maroslaw/rainyday.js/blob/master/rainyday.js Thanks in advance for any help and advice!

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  • Implementing default constructors

    - by James
    Implement the default constructor, the constructors with one and two int parameters. The one-parameter constructor should initialize the first member of the pair, the second member of the pair is to be 0. Overload binary operator + to add the pairs as follows: (a, b) + (c, d) = (a + c, b + d); Overload the - analogously. Overload the * on pairs ant int as follows: (a, b) * c = (a * c, b * c). Write a program to test all the member functions and overloaded operators in your class definition. You will also need to write accessor (get) functions for each member. The definition of the class Pairs: class Pairs { public: Pairs(); Pairs(int first, int second); Pairs(int first); // other members and friends friend istream& operator>> (istream&, Pair&); friend ostream& operator<< (ostream&, const Pair&); private: int f; int s; }; Self-Test Exercise #17: istream& operator (istream& ins, Pair& second) { char ch; ins ch; // discard init '(' ins second.f; ins ch; // discard comma ',' ins second.s; ins ch; // discard final '(' return ins; } ostream& operator<< (ostream& outs, const Pair& second) { outs << '('; outs << second.f; outs << ", " ;// I followed the Author's suggestion here. outs << second.s; outs << ")"; return outs; }

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  • Do you use an exception class in your Perl programs? Why or why not?

    - by daotoad
    I've got a bunch of questions about how people use exceptions in Perl. I've included some background notes on exceptions, skip this if you want, but please take a moment to read the questions and respond to them. Thanks. Background on Perl Exceptions Perl has a very basic built-in exception system that provides a spring-board for more sophisticated usage. For example die "I ate a bug.\n"; throws an exception with a string assigned to $@. You can also throw an object, instead of a string: die BadBug->new('I ate a bug.'); You can even install a signal handler to catch the SIGDIE psuedo-signal. Here's a handler that rethrows exceptions as objects if they aren't already. $SIG{__DIE__} = sub { my $e = shift; $e = ExceptionObject->new( $e ) unless blessed $e; die $e; } This pattern is used in a number of CPAN modules. but perlvar says: Due to an implementation glitch, the $SIG{DIE} hook is called even inside an eval(). Do not use this to rewrite a pending exception in $@ , or as a bizarre substitute for overriding CORE::GLOBAL::die() . This strange action at a distance may be fixed in a future release so that $SIG{DIE} is only called if your program is about to exit, as was the original intent. Any other use is deprecated. So now I wonder if objectifying exceptions in sigdie is evil. The Questions Do you use exception objects? If so, which one and why? If not, why not? If you don't use exception objects, what would entice you to use them? If you do use exception objects, what do you hate about them, and what could be better? Is objectifying exceptions in the DIE handler a bad idea? Where should I objectify my exceptions? In my eval{} wrapper? In a sigdie handler? Are there any papers, articles or other resources on exceptions in general and in Perl that you find useful or enlightening.

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  • overloading new/delete problem

    - by hidayat
    This is my scenario, Im trying to overload new and delete globally. I have written my allocator class in a file called allocator.h. And what I am trying to achieve is that if a file is including this header file, my version of new and delete should be used. So in a header file "allocator.h" i have declared the two functions extern void* operator new(std::size_t size); extern void operator delete(void *p, std::size_t size); I the same header file I have a class that does all the allocator stuff, class SmallObjAllocator { ... }; I want to call this class from the new and delete functions and I would like the class to be static, so I have done this: template<unsigned dummy> struct My_SmallObjectAllocatorImpl { static SmallObjAllocator myAlloc; }; template<unsigned dummy> SmallObjAllocator My_SmallObjectAllocatorImpl<dummy>::myAlloc(DEFAULT_CHUNK_SIZE, MAX_OBJ_SIZE); typedef My_SmallObjectAllocatorImpl<0> My_SmallObjectAllocator; and in the cpp file it looks like this: allocator.cc void* operator new(std::size_t size) { std::cout << "using my new" << std::endl; if(size > MAX_OBJ_SIZE) return malloc(size); else return My_SmallObjectAllocator::myAlloc.allocate(size); } void operator delete(void *p, std::size_t size) { if(size > MAX_OBJ_SIZE) free(p); else My_SmallObjectAllocator::myAlloc.deallocate(p, size); } The problem is when I try to call the constructor for the class SmallObjAllocator which is a static object. For some reason the compiler are calling my overloaded function new when initializing it. So it then tries to use My_SmallObjectAllocator::myAlloc.deallocate(p, size); which is not defined so the program crashes. So why are the compiler calling new when I define a static object? and how can I solve it?

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