rem: if ((read_buffer_len < N) && (N < 1024)) { read_check(buffer_f_in); }
context: static void readfd(int fd,char *buffer,int N){	int  ret;	int total=0;  		if ((read_buffer_len < N) && (N < 1024)) {		read_check(buffer_f_in);	}		while (total < N) {		if (read_buffer_len > 0 && buffer_f_in == fd) {			ret = MIN(read_buffer_len,N-total);			memcpy(buffer+total,read_buffer_p,ret);			read_buffer_p += ret;			read_buffer_len -= ret;			total += ret;			continue;		} 		no_flush_read++;		io_flush();		no_flush_read--;		ret = read_unbuffered(fd,buffer + total,N-total);		total += ret;	}	stats.total_read += total;}