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#include <plan9.h>#include <fcall.h>#include <u9fs.h>#include <sys/time.h> static longgetseed(void){	struct timeval tv;	long seed;	int fd, len; 	len = 0;	fd = open("/dev/urandom", O_RDONLY);	if(fd > 0){		len = readn(fd, &seed, sizeof(seed));		close(fd);	}	if(len != sizeof(seed)){		gettimeofday(&tv, nil);		seed = tv.tv_sec ^ tv.tv_usec ^ (getpid()<<8);	}	return seed;} static int seeded; voidrandombytes(uchar *r, uint nr){	int i;	ulong l; 	if(!seeded){		seeded=1;		srand48(getseed());	}	for(i=0; i+4<=nr; i+=4,r+=4){		l = (ulong)mrand48();		r[0] = l;		r[1] = l>>8;		r[2] = l>>16;		r[3] = l>>24;	}	if(i<nr){		l = (ulong)mrand48();		switch(nr-i){		case 3:			r[2] = l>>16;		case 2:			r[1] = l>>8;		case 1:			r[0] = l;		}	}}