Registers 0 and 1 contain the name of the application program (in EBCDIC characters) with which the LU is to establish a session:

Register 0:

First 4 characters of name (left-adjusted)

Register 1:

Last 4 characters of name (left-adjusted)

Registers 2–14:

Restored to entry contents

Register 15:

Return code:

0:

Application program was found and the name was placed in registers 0 and 1.

Nonzero:

Application program was not found and the name was not placed in registers 0 and 1.