@echo OFF
REM ********************************************************************
REM *** DiskFree.bat - Display how much disk space is available on a ***
REM ***                drive, and set the DISK_FREE environment      ***
REM ***                variable to that amount.  This batch file is  ***
REM ***                very specific to COMMAND.COM under MSDOS      ***
REM ***                version 5.0 and is not guaranteed to give     ***
REM ***                correct results in any other circumstance.    ***
REM ***                                                              ***
REM *** Here's another method for free disk space for drive C:       ***
REM *** CEnvi reg.dl=3;reg.ah=0x36;interrupt(0x21,reg);              ***
REM ***       DISKFREE=reg.cx * reg.ax * reg.bx;                     ***
REM ********************************************************************

if "%1" == "" GOTO SHOW_HOW
if not "%2"=="" GOTO SHOW_HOW
dir %1:\NUL | find "bytes free" | cenvi DISK_FREE = atol(gets()) / 1024
ECHO DRIVE %1 HAS %DISK_FREE% K-BYTES FREE
GOTO FINI

:SHOW_HOW
ECHO DiskFree.bat - Show how much disk space is available on a drive, in kilobytes,
ECHO                and set DISK_FREE environment variable to that size
ECHO USAGE: DiskFree DriveLetter
ECHO Example: DiskFree C
GOTO FINI

:FINI