Data Organization in C programming language

Before we start doing file input/output let us first find out how data is organized on the disk. All data stored on the disk is in binary form. How this binary data is stored on the disk varies from one OS to another. However, this does not affect the C programmer since he has to use only the library functions written for the particular OS to be able to perform input/output. It is the compiler vendor’s responsibility to correctly implement these library functions by taking the help of OS. This is illustrated in Figure