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fseek
Syntax:
  #include <stdio.h>
  int fseek( FILE *stream, long offset, int origin );

The function fseek() sets the file position data for the given stream. The origin value should have one of the following values (defined in stdio.h):

Name Explanation
SEEK_SET Seek from the start of the file
SEEK_CUR Seek from the current location
SEEK_END Seek from the end of the file

fseek() returns zero upon success, non-zero on failure. You can use fseek() to move beyond a file, but not before the beginning. Using fseek() clears the EOF flag associated with that stream.