#include <u.h>#include <libc.h>#include <bio.h>#include <mach.h> char *_hexify(char *buf, ulong p, int zeros){	ulong d; 	d = p/16;	if(d)		buf = _hexify(buf, d, zeros-1);	else		while(zeros--)			*buf++ = '0';	*buf++ = "0123456789abcdef"[p&0x0f];	return buf;}