C/C++ :: Getting Info From Binary File Into A Struct
Apr 19, 2015
Your goal is to open this struct of students (the binary file). Once open, the first job is to print out each student. Afterwards, display all students with a gpa of 3.5 and higher. Finally, display all students with the major of Computer Science or Game Programming. Be sure to title each category of items.
He gave us a .cpp file and a .h file that we're suppose to use to run the program. He doesn't want us to change his original code, except we can add the needed code to run his code (i.e. Struct & Main).
My problem is that I get an Abort() crash message in VS2013 when I try to run it. Now, in line 95 of the cpp file if I replace the char* with "", it runs fine showing the GPA with blank entries for the other print parameters. I've read the Binary Files chapter of the Pearson textbook several times and it doesn't have anything to say about working with char pointers.
Header file:
#pragma once //Professor's code
struct StudInfo //Start of my code {
char* fName;
char* lName;
char* major;
double gpa;
I'm trying to make a program that you input your login info and it writes that info to a text file. Then, later on once I get my problem fixed, the program will read the info to the user. my code is as follows(the input part is a bit lengthy):
I'm having a little problem where after reading a file I'm unable to update my struct with some particular info. It is actually a linkedlist. This is my struct:
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.
Below is the code for reading a struct that was stored in a binary file. Problem is while reading from file I get the name without first character and age is always equal to zero which it should not be.
I have a file in which I have written a structure called "Record".
Here is the struct definition:
Code:
#define IDSIZE 10 struct Record{ char id[IDSIZE]; int score; };
Here's the code where I wrote to the file:
Code:
Record record; char* id = "H12345678"; int score = 50; record.id = id; record.score = score; file.write((const char*)&record, sizeof(record)); }
Here's a screenshot of the file in windows: [URL].... To the left is the id, 9 characters. To the right, well I'm assuming that's the score that I wrote.
And here's the problem, reading from the binary file:
Code:
Record record; fstream file(argv[1], ios::in | ios::binary); if(!file){ cerr << "Could not open the file." << endl; return 1; } char* id = new char[IDSIZE];
[Code]...
The ID reads perfectly. The score...always returns 0, despite that it should show "50".
I need to take info in the following format (no blank/skipped lines):
last name, first name street address city, state zip code
And dynamically allocate space for it. I need to use structs, and I need to use an array of pointers to structs to point to them. I know I probably have quite a few problems with my code, but so far, I am able to store and print back the data without issue. In the following code, I only make the loop run 3 times just so I can test it with manual input into the console, but eventually the max will be 50, or until end of input (will be doing IO redirection with a txt file).
Like I said, I can store and print the data fine, but am getting a segmentation fault when trying to sort the info.
I am parsing a binary data file by casting a buffer to a struct. It seems to work really well apart from this one double which is always being accessed two bytes off, despite being in the correct place.
If I attempt to print GROSS using printf("%f", row->GROSS) I get 0.0000. However, if I change the type of GROSS to char[8] and then use the following code, I am presented with the correct number...
Code:
typedef struct example { double d; }
example; example *blah = (example*)row->GROSS; printf("%f", blah->d);
I need to transfer the content from the file text.txt to file sort.txt . The data in the text.txt is "struct" (info about people)but the same data needs to be sorted by the name and sent to sort.txt by using a function .
I am looking for a way that I could check the information of a folder and a drive, to show the data size and storage amount (KB, MB, GB). This is so that I can compare the size of a folder to the storage capacity of a disk drive.
I'm trying to open a text file with the name "text.txt", for the purpose of only displaying in the console an specific part of the text file. For example, if I got "This is a test [TEXT] This is the message that should display [/TEXT] this is the end of the file", I want only "This is the message that should display" to be the output, the thing is that I can't imagine anyway of doing that. what I should do?
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'm a beginner at programming and I'm not sure how to read in information from a text file. What I want to do is take a text file which contains around 20 rows and 3 columns of numbers, and put these into an array which can then be used for performing calculations. How do I do this? Would I need to declare the size of the array beforehand? When accessing my file, do I include the full address?
The relevant part is lines 29-33:
Code: #include <stdio.h> #include <stdlib.h> #include <math.h> /* this is a simpllified code using BEM equations */ main()
I'm intrested in creating programs of games and such which learns while playing and saving the information for further use. For example a tic tac toe game where the program saves evry game it won or lost and creates a tree of some kind that store the information of the game and save it in a file when the program is being quit. The problem i'm having is how to save a tree in a file efficently.
I have a tab separated file that consists of 10 columns. (classical txt file).the third column is the one interesting to me it consists of some strings like :
according to the value in the third column i wish to split my text file sot that i have files string1.txt string2.txt and string3.txt such that each file contains the whole line. how to do it in c++ with hash tables (maps) and all those fancy tools all ready and waiting for me to use them but in c i am crippled.
My idea was to first go through the file, hash all values in tht third column so i get a unique set of elements and then for each distinct string(element) in the third column create a file pointer, then go once more through the file and as I encounter a specific string(element) type, write the whole line into the appropriate file.
I have a program that gives the user the option to create an employee ID, name, address and so on. It also has the option to search employee by employee ID.
What I want to know is how to add and replace employee info. For example employee changes address. Also how to delete employee information from text file.
Here's my code:
//This program uses file input and output for an employee information system. #include <iostream> #include <string> #include <fstream> using namespace std; int main(){ ifstream inFile; //declare ifstream as inFile and ofstream as outFile ofstream outFile;
I'm having trouble in getting my program to read from a file and put all the proper data into its proper class variables. I have a class (called Champion) that has string variable for a name and a vector of strings for items. I also have a vector of Champion that holds multiple champions. Here's my code:
I'm trying to read information from a file and put the data into vectors of its appropriate type. For example: the file will have an int ID, string firstname, string lastname, double salary, int hours_per_week, and string work_position. All this data is separated by ";". I don't know how to read this file into the appropriate vectors: vector<int> ID, vector<string> fname, vector<string> lname, vector<double> salary, vector<int> hpw, vector<string> work.
I am trying to use a combination of windows batch scripts as well a C++ program to put users data into one single .CSV file. Right now, I have a batch file that will output data from the command line into multiple .txt files. These files are mac.txt, serialnumber.txt, computermodel.txt, and computer name.txt. What I want to do, is to have users run the batch file, which will in turn run the .exe C++ file which will concatenate all their data into one file, computerinfo.csv. The file format for this file would be to have the mac address, serialnumber, computer model, and computer name all in their own column.
My main issue is that these individual files don't have the format that I would like, but based on the command prompt functions, there isn't really any good format. For example, the mac.txt file has the following format:
Physical Address Transport Name =================== ========================================================== xx-xx-xx-xx-xx-xx DeviceTcpip_{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} yy-yy-yy-yy-yy-yy Media disconnected zz-zz-zz-zz-zz-zz Media disconnected
but all I really want is xx-xx-xx-xx-xx-xx
The other files have other issues with format, but if I can figure out this one then the others should be a piece of cake.
Also, I want the output of this to all go in one row, and as other users run this file, they will go into new rows without touching the rows above.
