C প্রোগ্রামিং ও অ্যাডভান্স File অপারেশন

Submitted by tushar pramanick on Mon, 01/02/2012 - 16:39

In last hour's lesson you learned the basics of reading and writing disk data files. In this lesson you'll learn more about communication with disk data files. The main topics discussed in this hour are

    Random access to files
    Reading or writing binary data
    Redirecting the standard streams

In addition, the following C I/O functions are introduced in this lesson:

    The fseek(), ftell(), and rewind() functions
    The fscanf() and fprintf() functions
    The freopen() function




Summary

  •     The file position indicator can be reset by the fseek() function.
  •     The ftell() function can tell you the value of the current file position indicator.
  •     The rewind() function can set the file position indicator to the beginning of a file.
  •     After you specify the mode of the fopen() function for the binary file, you can use the fread() or fwrite() functions to perform I/O operations on binary data.
  •     Besides the fact that the fscanf() and fprintf() functions can do the same jobs as the scanf() and printf() functions, the fscanf() and fprintf() functions also allow the programmer to specify I/O streams.
  •     You can redirect the standard streams, such as stdin and stdout, to a disk file with the help of the freopen() function.

 

Related Items

Using the Precision Specifier

Using the Precision Specifier

Aligning Output

Aligning Output
As you might have noticed in the previous section, all output is right-justified. In other words, by default, all output is placed on the right edge of the field, as long as the field width is longer than the width of the output.

 

Adding the Minimum Field Width

Adding the Minimum Field Width

Converting to Hex Numbers

Converting to Hex Numbers

Revisiting the printf() Function

Revisiting the printf() Function

The printf() function is the first C library function you used in this book to print out messages on the screen. printf() is a very important function in C, so it's worth it to spend more time on it.