binary file
I wrote a program that out puts a binary file. I have another program that reads in the binary file. I cannot get back the original data. How would I get back to the original data.
I am using the following to read the binay file
char buffer[4];
while(!infile.eof)
{
infile.read((char *) &z, sizeof(z));
cout << z << endl;
}
???? please help.
I keep getting back garbage.
Thanks.
Can you post a bit more code, in code tags. What is z?
You shouldn't control the loop using eof() either, instead use the return code from the read function.
When all else fails, read the instructions.
If you're posting code, use code tags: [code] /* insert code here */ [/code]
z is a double.
I wrote the binary file with this:
outfile.write(((char *) &z),sizeof(z));
Did you open it in binary mode?
Can you post more code? Preferably something that is close to compilable.
When all else fails, read the instructions.
If you're posting code, use code tags: [code] /* insert code here */ [/code]
keep in mind, binary isnt like textpad kinda stuff so what it returns may be differant than what ya put in
-Tootles
*-*
"...since anyone who is anyone knows C..." -Peter Cellik
Code:#include <iostream> #include <math.h> #include <fstream> #include <stdlib.h> #include <iomanip> using namespace std; int main() { unsigned int x; double z; char buffer[4]; ifstream infile("data.bin", ios::binary); infile.read(buffer,4); while(!infile.eof()) { infile.read(buffer,4); infile.read((char *) &z, sizeof(z)); cout << z << endl; } infile.close(); return 0; }
Here, I knocked this up as a quick example:
In your code, what's the 4 byte buffer all about?Code:#include <iostream> #include <fstream> using namespace std; int main(void) { double d1 = 10.5, d2 = 0; fstream myfile("out.dat", ios::out | ios::binary); if (!myfile) { perror("out.dat"); return(0); } myfile.write((char *) &d1, sizeof(d1)); myfile.close(); myfile.open("out.dat", ios::in | ios::binary); if (!myfile) { perror("out.dat"); return(0); } myfile.read((char *) &d2, sizeof(d1)); myfile.close(); cout << d2 << endl; return(0); }
>>keep in mind, binary isnt like textpad kinda stuff so what it returns may be differant than what ya put in
What are you talking about?!
When all else fails, read the instructions.
If you're posting code, use code tags: [code] /* insert code here */ [/code]
Binary isnt plain text what you think it will return isnt always it, binary is more compressed (thats not thee word I want but you get the idea)so whats returned doesnt look like plain text (not supposed to)
"...since anyone who is anyone knows C..." -Peter Cellik
