These operations are available in both the traditional syntax and free-form syntax.
The IN and OUT operations allow you to retrieve and write one or all data areas in a program, depending on the factor 2 entry.
The IN and OUT operations also allow you to control the locking or unlocking of a data area. When a data area is locked, it can be read but not updated by other programs or procedures.
During the actual transfer of data into or out of a data area, there is a system-internal lock on the data area. If several users are contending for the same data area, a user may get an error message indicating that the data area is not available.
A data area data structure is automatically read and locked
at program initialization time, and the contents of the data structure are
written to the data area when the program ends with LR on. If the data area
for a data area data structure is not found, it will be created with an initial
value of blanks. If the library list was searched for the data area, the new
data area will be created in QTEMP. 
In free-form, the DTAARA(*AUTO) keyword specifies that the
data structure is a data area data structure.
In fixed-form, a data structure defined with a U in position 23 of
the definition specifications indicates that the data structure is a data
area. 
In some cases,
you can use the IN, OUT and UNLOCK operation codes to specify
further operations for the data area.
For a free-form definition, you also specify *USRCTL as a parameter.
For a fixed-form definition, you specify the DTAARA keyword. 
If the data area for a data area data structure is not found, it will be created with an initial value of blanks. If the library list was searched for the data area, the new data area will be created in QTEMP.
Specify UDS on a fixed-form definition specification for the data area and leave
the name blank. 
Specify *N as the name on a free-form definition
and specify the DTAARA keyword without a name. 
To define the *PDA you may specify the DTAARA(*PDA) keyword on the definition specification for the data area, or specify *PDA in factor 2 of a *DTAARA DEFINE statement.