32-bit unsigned integer

Unsigned integers are used wherever possible, which is nearly everywhere. This type is called glui32.

32-bit signed integer

This type is called glsi32. Rarely used.

References to library objects

These are pointers to opaque C structures; each library will use different structures, so you can not and should not try to manipulate their contents. See Opaque Objects.

Pointer to one of the above types

Pointer to a structure which consists entirely of the above types.

unsigned char

This is used only for Latin-1 text characters; see Character Encoding.

Pointer to char

Sometimes this means a null-terminated string; sometimes an unterminated buffer, with length as a separate glui32 argument. The documentation says which.

Pointer to void

When nothing else will do.