ref: 72be22cd3ad8236dba47d3c56d1ba8af5b16a1c2
dir: /sys/src/libbio/btestprint.c/
#include <u.h>
#include <libc.h>
#include <bio.h>
void
main(int argc, char **argv)
{
Biobuf b;
char *s;
int n;
n = atoi(argv[1]);
s = malloc(n+1);
memset(s, 'a', n);
s[n] = '\0';
Binit(&b, 1, OWRITE);
Bprint(&b, "%s\n", s);
Bflush(&b);
}