C :: Create File To Write Text And Read Back The File Content
Mar 15, 2013
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(){
I have looked through te tutorials here, and even google it, as well as tried to follow the power points from my class..but I still can't seem to figure out how to make this code work correctly.. Basically I have to create a file called grade and write to it a student name and their grade score, and then read from the file all students names and there grade and display this on the screen as well as calculate the grade average for all of the students and display it.
Well I am able to write to the text file, but I can't seem to get the rest to work. I can't figure out how to read from the text file..Here is my code below.
write a sample code that does something similar write to text file string and numbers and then reads from it.
#include <iostream> #include <fstream> using namespace std;
I'm trying to read all content from a text file into a string. This is the code I'm using for it (I know there are other, maybe better ways to do it but I'd like to stick to this for now):
char* buffer; std::string data; FILE* fp = fopen("textfile.txt", "rb"); if (!fp) { printf("Can't open file");
[Code] ....
So my problem is that I get an exception when I try to free the memory -> 0xC0000005: Access violation reading location 0x51366199
I even get the exception when I try to free it immediately after calloc() but why this is.
And if I use buffer = (char*)malloc(lSize); I don't get any exceptions.
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.
A user enters a query and other users reply to it. But it creates a problem here. After adding queries, if I wish to reply to query in between then it adds a redundant entry in file. 1st entry is the original query without reply and 2nd entry is the same query now with a reply added. I want only 1 entry of the query along with replies.Here is the code:
write a text up to 1000 characters, and get it back. the end of the text is detected though EOF on a new line or reaching 1000 characters.(EOF=ctr-Z on a new line)
I mainly have problem how to bring the EOF work probably. it doesn't react when I press ctrl-z directly?
Code: int i; char Text[1000]; printf("write the text: "); gets(Text); for(i=0;i<=1000;i++){
I would like to write a complete structure array to a file and read it back, recovering all the data. I have tried the following:
Code:
#include <stdio.h> #include <string.h> #define NUM 256 const char *fname="binary.bin"; typedef struct foo_s { int intA; int intB; char string[20];
[Code]...
//---------------------------------------------------- but the mac field is reading back some random value repeatedly. Why is that? And how do I fix this?
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
I am writing a simple file/text parser to read a config file for some code I am working on. It's dead simple and not particularly smart but it should get the job done. The code reads a config file:
Here is where it gets wierd. You'll notice that there is an unused variable (filepath) in the config struct. This variable is not referenced or used anywhere in the code, ever. Yet if I comment out the declaration of char filepath[1024], the code segfaults partway through the read_config() function.
My best guess is that there is a buffer overflow elsewhere and it just so happens that the memory allocated for filepath happened to be there to catch it up until now, but I can't work out where it might be happening. With the declaration commented out, the read_config() function gets as far as reading the "padding" variable before it crashes. Yet when the declaration is there, then all the variabled are read correctly and everything seems to work.
getting hex from a text file and writing it to a different file. I made a program to dump hex from files into a text file and now I need it to save the hex to the original file. Here is my code to save the hex:
this is my read/write functions based the read from the last post! then went nuts with it! used the %19s%*s on the write to the file, solved all the probs on the read side! but any refining on this would be great. This is another program that i started with the forums, and started going my own direction!
I'm looking to write a program in C/C++ to traverse a Fasta file formatted like:
>ID and header information SEQUENCE1 >ID and header information SEQUENCE2
and so on
in order to find all unique sequences (check if subset of any other sequence) and write unique sequences (and all headers) to an output file.
My approach was:
Prep: Copy all sequences to an array/list at the beginning (more efficient way to do this?)
Grab header, append it to output file, compare sequence for that header to everything in the list/array. If unique, write it under the header, if not, go on.
However, I'm a little unsure as to how to approach reading the lines in properly. I need to read the top line for the header, and then "return?" to the next line to read the sequence. Sometimes the sequence spans more then two lines, so would I use > (from the example above) as a delimiter? If I use C++, I imagine I'd use iostreams to do the reading.
How to read some characters from file, I know we can move a pointer to some position using seekg() & seekp() function, get current position of the pointer through tellg() & tellp() functions. By moving the pointer to appropriate position using seekg(), we can read the whole line using getline() function. But is there any function which read certain characters from the current position of the pointer and write certain characters from current position of the pointer.
How to read some characters from file, I know we can move a pointer to some position using seekg() & seekp() function, get current position of the pointer through tellg() & tellp() functions. By moving the pointer to appropriate position using seekg(), we can read the whole line using getline() function. But is there any function which read certain characters from the current position of the pointer and write certain characters from current position of the pointer.
I am reading my file (20GB) line by line using boost like this
PHP Code:
boost::interprocess::file_mapping* fm = new boost::interprocess::file_mapping("E:Mountain.7z", boost::interprocess::read_only); boost::interprocess::mapped_region* mr = new boost::interprocess::mapped_region(*fm, boost::interprocess::read_only);
I am writing a program that models the ups & downs of a particular stock. Everything is pretty much done, except that I need to create another event to notify that saves the following information to a file when the stock's threshold is reached: date & time, stock name, initial value & current value. I have something like this so far:
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.IO;
[Code]...
I feel like i need something along the lines of
s.stockEvent += new Delegate( ???? ) in my myFile class so it know when the threshold is reached, to write the information of the current stock to the file.
Explain me a working code to read and write a file using serial communication.and i need to store that file.I know normal file handling in C, but how it is through serial port i am not getting.
