PROC fsize&:(f$)

	LOCAL pinfo$(16),ppinfo%,fname$(20),err%,ret&
	LOCAL ax%,bx%,cx%,dx%,si%,di%	/*  variables MUST be in this order  */

	ppinfo% = ADDR(pinfo$) + 1	/*  pinfo$ is P_INFO struct  */
	fname$ = f$ + CHR$(0)		/*  name must be zero-terminated  */

	ax% = $0800					/*  $08 is subfunction number  */ 
	bx% = ADDR(fname$) + 1          
	cx% = ppinfo%
	dx% = $00
	di% = $00
	si% = $00

	err% = OS($87,ADDR(ax%))		/*  $87 is FilStatusGet interrupt  */
	
	IF (err% AND 1)
		ret& = (ax% AND $FF) - 256
	ELSE
		POKEB ADDR(pinfo$),16
		ret& = PEEKL(ADDR(pinfo$) + 5)
	ENDIF

	RETURN ret&

ENDP