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/*
* This file lifted in toto from 'Dlibs' on the atari ST (RdeBath)
*
*
* Dale Schumacher 399 Beacon Ave.
* (alias: Dalnefre') St. Paul, MN 55104
* dal@syntel.UUCP United States of America
* "It's not reality that's important, but how you perceive things."
*/
#include <stdio.h>
static int _bsearch; /* index of element found, or where to
* insert */
char *bsearch(key, base, num, size, cmp)
register char *key; /* item to search for */
register char *base; /* base address */
int num; /* number of elements */
register int size; /* element size in bytes */
register int (*cmp) (); /* comparison function */
{
register int a, b, c, dir;
a = 0;
b = num - 1;
while (a <= b) {
c = (a + b) >> 1; /* == ((a + b) / 2) */
if ((dir = (*cmp) ((base + (c * size)), key))) {
if (dir > 0)
b = c - 1;
else /* (dir < 0) */
a = c + 1;
} else {
_bsearch = c;
return (base + (c * size));
}
}
_bsearch = b;
return (NULL);
}
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