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MSDNMoves the file pointer to a specified location.
int fseek(FILE *stream, long offset, int origin);Parameters    stream 
        Pointer to FILE structure. 
    offset 
        Number of bytes from origin. 
    origin 
        Initial position. 
Return Value    If successful, fseek returns 0. Otherwise, it returns a nonzero value. On devices incapable of seeking, the return value is undefined.
Example複製程式
// crt_fseek.c
/* This program opens the file FSEEK.OUT and
 * moves the pointer to the file's beginning.
 */
#include <stdio.h>
int main( void )
{
   FILE *stream;
   char line[81];
   int  result;
   stream = fopen( "fseek.out", "w+" );
   if( stream == NULL )
      printf( "The file fseek.out was not opened\n" );
   else
   {
      fprintf( stream, "The fseek begins here: "
                       "This is the file 'fseek.out'.\n" );
      result = fseek( stream, 23L, SEEK_SET);
      if( result )
         perror( "Fseek failed" );
      else
      {
         printf( "File pointer is set to middle of first line.\n" );
         fgets( line, 80, stream );
         printf( "%s", line );
      }
      fclose( stream );
   }
}
 Output複製程式
File pointer is set to middle of first line.
This is the file 'fseek.out'.