Function 3Bh Change Current Directory

mov dx, seg Dir

mov ds, dx

mov dx, offset Dir ;ds:dx points to name of new directory

mov ah, 3Bh ;Change Current Directory

int 21h

jc error_handler ;carry set means error

Change Current Directory (Function 3Bh) changes the current directory to a specified path.

Parameter

Dir

Points to a zero-terminated ASCII string that specifies the new current directory. This string must be a valid MS-DOS directory name and cannot contain wildcards.

Comment

If a drive other than the default drive is specified as part of the new directory path, this function changes the current directory on that drive but does not change the default drive. Set Default Drive (Function 0Eh) can be used to change the default drive.

Return Value

If the function is successful, the carry flag is clear. Otherwise, the carry flag is set and the AX register contains an error value, which may be 0003h (ERROR_PATH_NOT_FOUND).