! A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
X"87" 18.2.2..2
X"88" 18.2.2..2
X"F4" - pack byte 2.5.3.2
X"F5" - unpack byte 2.5.3.2
X/Open environment variables 2.4
XFHCONV environment variable 5.1.5.3
XOR logic operator 1.1.2.5
, 2.5.1
, 2.5.3.2
XREF Compiler directive 17.1.1
integrated preprocessor 17.1.1