to fix this: sort.c -> line 415 change: xmove_fd(xopen3(str_o, O_WRONLY, 0666), STDOUT_FILENO); to: xmove_fd(xopen3(str_o, O_WRONLY|O_CREAT|O_TRUNC, 0666), STDOUT_FILENO);
There is a hotfix for it: http://busybox.net/downloads/fixes-1.17.3/busybox-1.17.3-sort.patch