filename.gsym

global symbol file in the data-manager (dm) account. Global symbols are used to reference the system-wide set of global variables.
Attribute 0: Global symbol name is the item-id
Attribute 1: item type code
c character
h half-tally (1 byte)
t tally (2 bytes)
d double-tally (4 bytes)
n constant
s 6-byte storage register
e 8-byte quad tally
b bit the displacement for the bit definition is the actual number of bits. Divide by 8 to find the byte the bit is stored in.
Attribute 2: variable displacement in hexadecimal.
Attribute 3: variable register number in hexadecimal.