I have a std::vector of short ints that I need to write to a specific location in a binary file (without using .NET code). To that end, I wrote up this code:
Code:
ofstream fileStream (filePathString, ios::out | ios::binary);
int curPos = 2821;
fileStream.seekp(curPos);
int iter = 0;
while (iter < 1024*1024){
char bytesToWrite[2];
//Low byte
bytesToWrite[0] = LOBYTE(dataVector[iter]);
[Code]...
The code runs without crashing, but when I look at the file afterwards in a hex editor, every byte (even those outside the range I thought I was writing to) are replaced with 00. I suspect I'm missing something in my understanding of file streams. Did I write that code correctly? Seekp does move the pointer over the next byte to be overwritten, yes? Am I getting a memory leak somewhere?
Following is the program I wrote it basically takes 9 inputs and then save them into binary file. then print out the data stored in binary data and find inverse of it then print the inverse out. but its stuck in a loop somewhere.
Code: #include <stdio.h> int main() { int a[3][3],i,j; float determinant=0; int x; FILE *fp = fopen ("file.bin", "wb");
I am trying to get the code to read from the txt file one bite at a time and then write this bite into the binary file but i cant seem to get it working.
FILE *fpcust, *fpcustbin; //<<<<<-----point to both sales and customers text files, and the new .bin files for both char buffer; int ch; int ch1; fpcust = fopen("c:customers.txt", "r"); //<<<<-----pointing to the file fpcustbin = fopen("c:customers.bin", "wb"); //<<<<<-----pointing to the new binary file, opening in writing binary
except when the string exceed 11 characters. I guess it's because it has to pick a fixed sized for the string? but what if I want to always be able to have string up to 200 character? because now I can't exceed 11..I know writing a string with c_str() works, but I would like to write/read the structure in one shot.
So as a learning exercise, I am trying to read and write a binary tree to a file. After googling around, I decided to use a preorder traversal (including null nodes) to write the binary tree to the file. I got stuck trying to read a tree from a file. I can't figure out how to create an unknown number of nodes when they are needed. I could use an array, but that just seems bulky - plus it could run out of space. Is that what I have to do? I've heard of vectors before, but not very much.
if i have 2 variables for which values are given by the user,then,does the information get stored into the file in the name of the variable,or just like packs of information.....if the former is true,how to extract the information of a particular variable alone from the whole file?
int main () { FILE * pFile; long lSize; char * buffer; size_t result; pFile = fopen ( "myfile.bin" , "rb" );
[Code] .....
How to open binary for read and write? Why the buffer is char * buffer? i mean in binary u cant read chars . How can it be? how the data is represented? just like txt file? What the buffer will contain how to print this buffer???
My project is to get a file from a designated location in my computer and not just read, but grab the values from the user and make a count, sum, and average calculation of the numbers in my code. I am using the fstream library and I am trying I did do it, I got the values and calcualated them, however I want the values to be accessed from maybe my desktop or my drive, I want to know how to manipulate my code to get a path like C:UserDesktop and maybe executed from the path input or given. I dont know if this is possible, or easy to do. ALso I did copy some of this code from my teachers examples and I dont know exatly why the variables have to be initilized at zero, and I would like to know a little more on the Bitwise right shift breaker used in line 20 something.
Here is my code below.
#include <iostream>//For avergae functionality #include <fstream>//For the file commands, such as ifstream and the Bitwise right breakers(<< and >>). #include <iomanip> // To control the amount of decimals in my results desired. using namespace std; int main () { int aNumber=0; //Initilized at zero because of Stack Overflow:
The Problem You are part of a company writing a spreadsheet program. As you know, spreadsheets can be sorted on any column. You're part of the project is to write one binary tree function to sort the data [Hint: use different fields when inserting nodes in the tree.] and a second function to list it in either an ascending or descending sequence. [Note: Each of these functions may actually need to be a set of related functions.]
For sample data you will have a disk file containing information about Shakespeare's plays. Your first function should create a tree based on the sort selected by the user and the second function to display the data in the sequence selected by the user. Regardless of the column being sorted, data in individual records always be displayed in the same line of the output.
Input : Each record will contain the following information: First Performed 9 characters Printed 5 characters Title 26 characters Type 7 characters
Output : Tabular output should be aligned in columns with two spaces between each. All columns should have headings. It should be sorted on the column specified by the user.
Example (This sample data provided so you can test your program.) If the data is:
1595-96 1600 A Midsummer Night's Dream Comedy 1594-95 1623 Two Gentlemen of Verona Comedy 1596-97 1623 King John History 1597-98 1598 Henry IV, Part 1 History 1611-12 1623 The Tempest Comedy 1602-03 1623 All's Well That Ends Well Comedy
[Code]...
Source: [URL]...
Possible outputs are
1 - for a sort by title: First Performed Printed Title Type --------- ------- -------------------------- ------- 1595-96 1600 A Midsummer Night's Dream Comedy 1602-03 1623 All's Well That Ends Well Comedy 1606-07 1623 Antony and Cleopatra Tragedy 1599-1600 1623 As You Like It Comedy
[Code]....
2 - for a sort by first performed: First Performed Printed Title Type --------- ------- -------------------------- ------- 1590-91 1594? Henry VI, Part 2 History 1590-91 1594? Henry VI, Part 3 History 1591-92 1623 Henry VI, Part 1 History 1592-93 1623 Comedy of Errors Comedy 1592-93 1597 Richard III History
I would like to copy one bmp file to another using plain fstream (none 3-rd party library). I've managed to come up with something but I keep getting error:
Unhandled exception at 0x504A3442 (msvcr120d.dll) in ConsoleApplication1.exe: 0xC0000005: Access violation reading location 0x00380000.
when i try to write the content of the bmp files not the header, namely error occurs in this line:
Also i am not sure if i am doing it in a right way, meaning that even after solving this error i will copy the bmp file successfully.
Code:
// ConsoleApplication1.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <iostream> #include <fstream> using namespace std; struct BITMAPfileHEADER { unsigned short bfType;
One of my class assignments is to create a program that receive a .txt file containing a students name and their grades as follows:
John K. 99, 87, 57, 89, 90, 95 Amanda B. Jones 100, 88, 76, 99, 86, 92 etc..
The number of students is unknown until run time. You have to take those grades and average them weighing the first (4) at 10% a piece and the last (2) at 30% each.
Then return an output file with the students name and their letter grade A,B,C,D,F based on their computed score. In addition, on screen it needs to display the average scores for each Q1, Q2, etc. as well as the minimum and maximum for each test on the screen. I am having a hard time in assigning the scores to a variable so that they can then be computed as an average and then used to determine a letter grade. I have begun to write the code and am a bit stuck..here's what I have so far:
The Objective Of This Program Is To Create A File To Write Text And Read Back The File Content. To Do That I Have Made Two Function writeFile() To Write And readFile() To Read.The readFile() function works just fine but writeFile() doesn't.
How writeFile() function Works? when writeFile() function Execute It Takes Characters User Type And When Hit Enter(ASC|| 10) It Ask "More?(Y/N)" That Means What User Want? Want To Go Next Line Or End Input?
If "Y" Than Inputs Are Taken From Next Line Else Input Ends.
But The Problem Is When Program Encounters ch==10 It Shows "More?(Y/N)" And Takes Input In cmd variable.If cmd=='Y' I Mean More From Next Line Than It Should Execute Scanf Again To Take ch I Mean User Input.But Its Not!!! Its Always Showing "More?(Y/N)" Again And Again Like A Loop.
Code: #include <stdio.h> void writeFile(void); void readFile(void); int main(){
how do i decompress an input file and write the results into an output file?
also my do while loop is supposed to keep going unless the user selects the option to exit the program, instead it exits after finishing ay of the options.
I have a .txt file which I want to read from and then write a new text file, this time with sorted lines. It is easy to sort one value, but what about sorting entire lines based on one value?
I want to sort the lines based on the FIRST value.
