When I return mem add I cannot access the data in that add: in bin search tree
Curr=findMin(root);
cout<<"val: "<<Curr->barcode<<endl;
bst::hwareItem* bst:: findMin(hwareItem*& root){
while(root!=NULL){
root=root->left;
}
return root;
}
I am doing a project which I have to read, write and erase data from a NorFlash Memory. Then, I have to compare those data files in order to find errors.
Besides, I would like to know which is the best way to TEST errors in this kind of memories.
I am using NetBeans 7.3.1 for writting the code and Cygwin running on Windows XP Virtual Machine. The Memory Flash (S29JL064J 64 Megabit) is incorporated on an external board which is connected to an adapter board (using HDMI cable). This adapter is connected to the Laptop (using an USB).
if we don't provide the acces modifiers for base class and we need to manipulate the private data of base class in derived class. Is there anyway to acces the private data members? Here's a coding example
class A {
private :
int a;
};
class B : public class A {
public :
void displayA() { cout<<a<<endl; }
};
how i can acces the a of base class A in derived class B without acces modifiers.
I'm currently stuck whit a problem. I would like to access video memory of the console(Yes, only the black box) in C. I know how to do it in turbo pascal :
Var
video:array[0..4000] of char absolute $B800:0000;
But i don't know the numbers in C. I've searched for the numbers of the memory in C but i can't find it.
I am trying to use PCA, but it gives memory access violation error. Here is my sample code.
Code:
int main(...) {
.................
vector<float>input_array;
for(i=0;i<number_of_lines;i++) {
for(j=0;j<feature_vector_size;j++) {
input_array.push_back(read_feature[i][j]);
[code]....
I get a memory access violation when I run the below code. void createNewImage(int width, int height); this function deletes any current image data and creates a new image with the specified width/height and allocates the needed number of pixels dynamically. The new image contains four blocks with different color, red, blue, green, and black.
Code:
#include <iostream>
#include "image.h"
image::image() {
pixels = NULL;
width = 0;
height = 0;
[Code] .....
Under Microsoft, I use GlobalAlloc and GlobalFree to dynamically allocate and free memory. Intermittently GlobalFree is reporting error 998 (GetLastError() - Invalid access to memory location). I've checked my logs of addresses returned by GlobalAlloc against those being freed by GlobalFree and when the problem occurs the address causing the error has been allocated by GlobalAlloc and has not been freed before since allocation.
I can't reproduce it. Currently I'm checking for error 998 from GlobalFree and ignoring it if it occurs - which is not satisfactory. I have one function (AllocMem) that calls GlobalAlloc and checks for errors and another function (FreeMem) which calls GlobalFree and checks for errors.
My program uses AllocMem and FreeMem everywhere memory is required or freed. AllocMem and FreeMem are in a DLL. The program is heavily threaded and a different thread may call AllocMem to the one that calls FreeMem. I don't believe I've got a race condition etc as all the code in the program containing the AllocMem and FreeMem calls are part of a CriticalSection using the same variable.
What is a possible cause of this error?
I have CAN Dll program for my application,which was separately used.Now I have included the Drivers program into my application Program and I am having this error System Access Violation Exception:Attempted to read or write protected memory.i am attaching the Dll code and Application code which is throwing this error.
[CODE]
The CAN Dll Code
int receive_data(unsigned char *data_output, int *MsgId, XLportHandle g_xlPortHandle){
XLstatusxlStatus, xlStatus_new;
XLevent xlEvent;
unsigned intmsgsrx=RECEIVE_EVENT_SIZE;
char *local_data ="11111111";
DWORD status;
xlStatus_new = xlSetNotification(g_xlPortHandle, &h, 1);
[code]...
My Application Code which is the receiver thread for accessing the messages got onto the CAN bus.
DWORD WINAPI Rcv_Msg(LPVOID param){
int*MsgId = new int;//msg id from CAN
intRcvVal;//0 = there is data in the queue; 1 = there is no data
unsigned int uMsgId;
*MsgId = 0;
unsigned char CanData[8];
[code]...
I am using the SDL library, and came across a way to access pixel data.
//A pointer to a surface structure
SDL_Surface *w = SDL_SetVideoMode(800,400,8,SDL_SWSURFACE);
//Casting a void pointer pointing to an array of memory locations(the pixels), to a pointer to an array of Uint8's.
//SDL_MapRGB() Returns an Uint32 containing the color 0,0,255,(0/255, i think it returns the transparency too, or else it would rather return a Uint24,not sure).
Then modifying the memory location, in this case the pixel at the middle of the window.
static_cast<Uint8*>(w->pixels)[(200*w->pitch)+400]=SDL_MapRGB(w->format,0,0,255);
What i seem to not understand is that, i cast pixels to Uint8*, which means I now have a pointer to an array of 8bit numbers, but SDL_MapRGB seemingly returns an Uint32 or Uint24 for a color composed of r,g,b, together without 'a' is 24bits(256=1b,256=1b,256=1b)=3b.
And then i somehow assign that pixel which is of 8bit at chosen location, an Uint24 or 32bit unsigned int.
How does this work?
I have some doubt regarding class data member accessing in another file.Follwing code showing error.
class A://file a.cpp
{
public:
int add;
int sub;
};
//file b.cpp
extern class A
void cal()
{
A::add=A::sub;
}
The problem is as following. First, I have 21 arrays named: integer abee1, abee2, ... , abee20 and myarray all with the same dimension of [51][4]. Next, in a loop of 20 circles, I fill myarray with random integers then copy it into abee1-20 (each one per iteration). Then, for each array (abee1-20), I want to calculate sum of all numbers in second column as cost of that array and store it in the a new array called arrayCosts[20][2] ( char arrayName, int arrayCost)- the name of array in the arrayName column and cost of that array into arrayCost column . After that, I want to sort arrayName based on the cost and extract the 3 top array with lowest cost. I know that I should do a search in the array to find these three. Finally, copy these three into 3 new array called elite1, elite2, elite3.I do not know what to do.
1-The following code is for making the sting name of abee1-20 in string made in each step of the loop.
for ( cc = 1 ; cc < 20; cc++)
{ string String = static_cast<ostringstream*>( &( ostringstream () << cc) )->str();
string array_name = "abee" + String;
I want to use array_name (for example in the first loop which array_name is “abee1” ) for reaching the abee1 (which is a filled array) after dong a search in the array called “arrayCosts”. This search retrieves the name of array but it is string and I want to have the array with the same name.
How does an object access its private data members in copy constructor.
The relevant part of the code: Code: C::C(const C &obj)
{
x = obj.x;
y = obj.y;
}
Normally the object1 called "obj" cannot access its private data members outside. But in this situation it can access. How can it be explained?
Here are the complete code:
Code:
#include <iostream>
using namespace std;
class C{
public:
C(int,int);
C(const C &);
[Code] .....
How I would store all the data. Also how would I access it after I store it. Side Note we are not allowed to use structures or objects.
For the purposes of this gradebook you should first provide a menu with the following options
-Add a new course Add a new student to a course Add grades for a student in a course Print a list of all grades for a student in a course Print a list of all students in a course Compute the average for a student in a course Compute the average for a course Store Gradebook (to a disk file) Load Gradebook (from a disk file)
-Each of these menu items should correspond to a function you will write.
-For the basic program each student will be represented by an ID number And each course by a course number
-Grades will be whole numbers only (no fractional part)
As indicated in the menu you will need to store and load using a disk file so that the data is retained.
Here are so limiting values in defining your data structures: Maximum Number of students (total) 100 Max number of courses 25 Max number of courses per student 4 Max number of grades per student per course 10
I want to connect an access database (.mdb) to my Windows Forms application - this I can do and I have no problems viewing my table in server explorer.
Some code example or template that I can use as a base to learn from - I have literally trawled Google and Youtube and cannot find what I am after.
What I want to do is have a basic form, 2 text boxes and a button to save the data to my database.
FirstName and LastName are the 2 boxes.
I have the following method to read in a data file using a struct and a doubly linked list.
The readFile method is as follows:
Code:
struct contact *readFile(char * FName,struct contact **ptrList) {
struct contact *head, *newContact;
FILE *fptr;
char oneLine[60];
char *sname, *fname, *phone,*company, *email;
[Code] .....
My struct definition is like this:
Code:
struct contact {
char sname[15];
char fname[15];
char phone[15];
char company[15];
char email[15];
struct contact *prev;
struct contact *next;
};
I have a .png file that my console app reads and puts into a structure that is saved as a file. The png is always the same so I thought I could just add it as a resource image to a resource file so it would be included in my program and not as a separate file. When I did that, the png shows up as a "SystemDrawingBitmap". If I examine this resource in a watch I see "Base" and "Static" members. Expanding those properties does not give me anything useful such as a pointer to the raw png data and its length in bytes.
If worse comes to worse, I can always make a hex dump of the png contents and then put the hex code into a CS file using static initialization.
Surely there is some way I can access the raw data internally and read the bytes into a byte array using C#
So, it seems I have a bug in my code:
Code:
char *mem = malloc(9), *bottom = malloc(3), *in = "abc";
int position = 2, i;
mem = "onetwo";
printf("OLD mem = %s
", mem);
[Code]....
What I'm trying to do is insert "abc" in the 3rd position of "onetwo". Results would be "oneabctwo", but all I get is crashing.
Is it possible to store data to CPU memory, if so how much memory can I store and how? Say I wanted to store an array, about 6MB in size?
View 1 Replies View RelatedThe file name is "movie.dat" and currently i was able to save data into the file in this order:
[movie_code] [movie_dur] [movie_title] [movie_rating] [movie_dir] [movie_genre] [movie_status]
[12345] [120] [Movie] [PG13] [Director] [Comedy] [Active]
I want to search for the "movie_code" and change the [movie_status] from Active to Inactive.
So lets say for example i have a movie code 12345 saved in my movie file. I want to change the value from "Active" to "Inactive"for argument sake.
This is the code i was trying to do it with:
Code:
FILE *movie_fp;
movie_fp = fopen("movie.dat", "r+b");
int m_code;
MOVIE movie_data;
printf("*** Welcome to the movie updater! ***
[Code].....
I have two puzzling issues I am dealing with.
Issue 1: I am using a stringstream object in a block of my program that needs to be visited repeatedly depending on a user's selection from a menu. I want the contents of this stringstream object to be cleared any time control gets to this part of the program. I have tried the clear and flush functions to no avail.
Issue 2: I am reading data from a source text file that would be regularly changed during the course of program run. After the program run is over, I am supposed to save the results(which is basically the source text file AND all updates) in a destination file. This destination file would then serve as the source file when next the program is run. In other words, I want a scenario where my results overwrite the original contents of the source file; implying that my source and destination files are now one, pretty much. How can I do this?
Using the C # programming language LED controller through which controls the array is connected to the controller via the RJ45 port. I already know the basics, I mean specifics, ie
Using the instructions and DLL included with the hardware, I want to read data from it, but I can not deal with it.
Model controller is "C-Power5200" and dll is "CP5200.dll".
I would like to:-pick the data-display-edit and - save in the controller.
To read the data I am using the function
CP5200_Net_Read (BYTE * pBuf, int nSize);
and to save
CP5200_Net_Write (const BYTE * pBuf, int nLength);
I have been asked to create a program that accesses an inventory file done in excel, look for a alpha-numeric code, which will be inputed by the user, and return to the user informations related to the position of that code, and informations related to the header of the column in which the code resides.
An example of the function I need the program to perform would be:
User inputs: 1429-R1
And the program returns: Marco's 6A, 8/21/2014, 3/7/2014.
using the following example of file:
Marco's 6A
Assessment 8/21/14 3/7/14
1584-R1 1584-R1 1584-R1
1461-2R1 1461-2R1 1461-2R1
1429-R1 1429-R1 1429-R1
I have a csv file (comma delimited text file really) and I have data ,about 6400 lines, and I need to read and display data from 1 line. At the bottom is sample data from my csv file.
I want to read onto the screen the 3rd item .. ie Test User 1 and the date and time at the end (the last 2 items).
I will enter in a number .. from which I will want to retrieve the appropriate record .. in this case I would enter in 514, 563 or 874 and get back the info for that record.
This is a DOS 16 bit application .. and I know that some of the data is in memory already but I am not sure how to tell .. or how to retrieve it.
I do have the ability to save the data to the file at any time .. so I can use that to ensure that the data is current in the text file before I retrieve the data from this 1 row.
I think that it may just be easier to get from the text file ? but I am not sure.
0000,7,0,"Test User 1",53c145cb,db,5,514,514,2014/07/12,10:27:23
0001,7,0,"Test User 2",53d7f,1903,10,563,563,2014/07/24,11:04:31
0002,7,0,"Test User 3",529c,5ffb03,0,874,874,2013/12/02,09:07:58
I am a database guy .. and I am just a bit lost when it comes to C programming as such.
So, if I'm right, computer store their data as binary values. So if I write int x = 5; , my computer converts the value of x from decimal (5) into binary (101) and stores it in memory as a a binary number. If I print that value on the screen that value is converted(by default) back into a decimal number before being printed on the screen.
Now, my question is if there is any way to print the value of x directly into binary(as it's stored in memory) without it being converted back into a decimal value?
I have a data buffer project in Windows 7 x64 embedded OS (using Visual Studio 2008), that would work simply like that:
One writer application will send data (no network protocols, just procedure call on the same machine) to my app like 20 packages per second, each data packages will be approximately 3 MB size and comes with a timestamp tag.
My application will store each data item for 100 minutes and then remove. (So I can calculate the total size from beginnig no need for dynamic allocation etc...)
Meanwhile there will be up to 5 reader applications which will query data from my app via Timestamp tag and retreive data (no updates or deletitions on data by reader apps).
So since the data in my buffer app can grow over 50GB I don't think that shared memory is going to work for my case.
I'm thinking about using Boost Memory Mapped Files or Windows API Memory Mapped Files.
So theoratically I will crate a fixed size File on harddisk (lets say 50GB) and then map some portion to RAM write the data to this portion, if the reader applications wants to use the data which is mapped currently on memory, then they will use directly, otherwise they will map some other potion of the file to their address spaces and use from there...
My problem is I haven't use Map File concept at all and I'm not a C++ developer so I'm not very familiar with the language fundementals. I've searched tutorials of boost and msdn for windows as well but there is not too much code example.
So I don't know how to map some portion of the data to memory and manage it, also how to search data in file or memory according to the timestamp tag. Yes there are codes for creating files and mapping the whole file to memory but none for dividing it into regions, aligning or padding the data which I need for my case.
I serialize a XML file, and i have this values here:
public class ServiceConfig {
public List<DatabaseDescriptor> Databases { get; set; }
} public class DatabaseDescriptor {
[XmlElement("Name")]
[Code] ....
I have a form1 which is a datagrid view and get's updated like this:
dataGridView1.DataSource = xmlData.Databases;
Now i have a button: get tables, and it opens up form 2, there it's supposed to appear all the tables of the selected Database, when i click on the row i get the database name so i get all the list of Tables from
DatabaseDescriptor
where
DatabaseDescriptor.Name == name
(I get this when i select the row)
But then on the 2nd form, i also have 2 textbox so i add a new table, i add the tablename and id. the new value should appear in the datagridview of the tables, and when i close it and reopen it, it should be there. Maybe i should concatenate first the values or something, how do i do?