Designing Games with Game Maker - YoYo Games

holds. (The name must exist. Otherwise the number 0 is returned.)
registry_exists(name) Returns whether the given name exists.
Actually, values in the registry are grouped into keys. The above routines all work on values
within the key that is especially created for your game. Your program can use this to obtain
certain information about the system the game is running on. You can also read values in
other keys. You can write them also but be very careful. YOU CAN EASILY DESTROY YOUR
SYSTEM this way. (Write is not allowed in secure mode.) Note that keys are again placed in
groups. The following routines default work on the group HKEY_CURRENT_USER. But you can
change the root group. So, for example, if you want to find out the current temp dir, use
path = registry_read_string_ext('\Environment','TEMP');
The following functions exist.
INI files
registry_write_string_ext(key,name,str) Creates an entry in the
key in the registry with the given name and string value.
registry_write_real_ext(key,name,x) Creates an entry in the key in
the registry with the given name and real value.
registry_read_string_ext(key,name) Returns the string that the given
name in the indicated key holds. (The name must exist. Otherwise an empty
string is returned.)
registry_read_real_ext(key,name) Returns the real value that the
given name in the indicated key holds. (The name must exist. Otherwise the
number 0 is returned.)
registry_exists_ext(key,name) Returns whether the given name exists
in the given key.
registry_set_root(root) Sets the root for the other routines. Use the
following values:
0 = HKEY_CURRENT_USER
1 = HKEY_LOCAL_MACHINE
2 = HKEY_CLASSES_ROOT
3 = HKEY_USERS