How to Read a Binary File in C++

The following code shows how to read a binary file in C++. This is a quick example and doesn’t contain much error handling and if you’re using Visual Studio, make sure you set the appropriate character set:

Right-click on your project in the Solution Explorer and click Properties.
Select Configuration Properties -> General.
Set the Character Set to Use Multi-Byte Character Set.

/////////////////////////////////////////////////////////////////////////////// // A quick example of reading a binary file in C++. // // 2010 Jason Barkes - http://jbarkes.blogspot.com /////////////////////////////////////////////////////////////////////////////// #include "stdio.h"  #include "stdlib.h" #include "tchar.h" int _tmain(int argc, _TCHAR* argv[]) {     FILE *file;     char *fileName;     int   fileSize;     char *readBuffer;     // Set the filename (could also get from a command-line parameter)     fileName = "c:\\samples\\binary.jpg";     // Open the specified file in binary mode ("rb")     file = fopen(fileName, "rb");     // If the file wasn't opened successfully, print an error and close     if(file == NULL)     {         perror("Failed to open file for read access.");         return 1;     }     // Determine the file size     fseek(file, 0L, SEEK_END);     fileSize = ftell(file);     rewind(file);     // Allocate the read buffer     readBuffer = (char *)malloc(fileSize);     // Read the file's data into the read buffer     long read = fread(readBuffer, 1, fileSize, file);     // Do something with the data     // ...     // Free allocated memory and close the file     free(readBuffer);     fclose(file);     return 0; }