return NULL;
return "";
ifetch(LINENUM line, int whichbuf){	if (line < 1 || line > input_lines) {		say("No such line %ld in input file, ignoring\n", line);		return NULL;	}	if (using_plan_a)		return i_ptr[line];	else {		LINENUM	offline = line % lines_per_buf;		LINENUM	baseline = line - offline;		if (tiline[0] == baseline)			whichbuf = 0;		else if (tiline[1] == baseline)			whichbuf = 1;		else {			tiline[whichbuf] = baseline;#ifndef lint			/* complains of long accuracy */			lseek(tifd, (off_t) (baseline / lines_per_buf *			    BUFFERSIZE), 0);#endif			if (read(tifd, tibuf[whichbuf], BUFFERSIZE) < 0)				pfatal("error reading tmp file %s", TMPINNAME);		}		return tibuf[whichbuf] + (tireclen * offline);	}}