Int 21H, AH=3BH

2 and higher

“CHDIR” - SET CURRENT DIRECTORY

      AH = 3Bh
      DS:DX -> ASCIZ pathname to become current directory (max 64 bytes)

CF clear if successful

          AX destroyed
      CF set on error
          AX = error code (03h) (see #01680 at AH=59h/BX=0000h)

if new directory name includes a drive letter, the default drive is not changed, only the current directory on that drive

changing the current directory also changes the directory in which FCB file calls operate

under the FlashTek X-32 DOS extender, the pointer is in DS:EDX

AH=47h,AX=713Bh,INT 2F/AX=1105h

Text based on Ralf Brown Interrupt List Release 61