45 lines
903 B
C
45 lines
903 B
C
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#include <stdio.h>
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#include <stdlib.h>
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/* Example 3 - jumping & getting element count */
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int main(void)
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{
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int ValRead;
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int Item;
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int Locn;
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FILE *fptr;
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/* Open the file from example 1 */
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fptr = fopen ("data.dat","rb");
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if ( fptr == NULL )
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{
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printf ("\nError opening input file - aborting ");
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exit (0);
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}
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/* Ask the user which value to jump to */
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printf ("\nWhich value do you wish to view ? ");
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scanf ("%d",&Item);
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/* Jump to this item */
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/* notice we move in steps of item size */
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Locn = Item * sizeof(int);
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fseek (fptr, Locn, SEEK_SET);
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/* And read a single integer in */
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fread (&ValRead, sizeof(int), 1, fptr );
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/* Display the read value */
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printf ("Item %d is %d\n",Item,ValRead);
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/* And close */
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fclose (fptr);
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/* All Done */
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return 0;
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}
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