String Atoms

When applications pass null-terminated strings to the GlobalAddAtom, AddAtom, GlobalFindAtom, and FindAtom functions, they receive string atoms (16-bit integers) in return. String atoms have the following properties:

• The values of string atoms are in the range 0xC000 (MAXINTATOM) through 0xFFFF.
• Case is not significant in searches for an atom name in an atom table. Also, the entire string must match in a search operation; no substring matching is performed.
• The string associated with a string atom can be no more than 255 bytes in size. This limitation applies to all atom functions.
• A reference count is associated with each atom name. The count is incremented each time the atom name is added to the table and decremented each time the atom name is deleted from it. This prevents different users of the same string atom from destroying each other's atom names. When the reference count for an atom name equals zero, the system removes the atom and the atom name from the table.