This means that the Control modifier is still in effect, although you have released the key. Re-pressing and releasing the key has no effect. To avoid this, you should always define all the columns to have the same modifier symbol. There is a handy short-hand notation for this, see below. The numeric notations use the same format as with keynumber .
Notable differences are the number symbols.
It should be noted that using numeric notation for the keysyms is highly unportable as the key action numbers may vary from one kernel version to another and the use of numeric notations is thus strongly discouraged. Next, you can leave off any trailing VoidSymbol entries from a key definition line. VoidSymbol denotes a keyboard action which produces no output and has no other effects either. For added convenience, you can usually get off with still more terse definitions. If you enter a key definition line with only and exactly one action code after the equals sign, it has a special meaning.