|GY28-6609-6_OPEN_CLOSE_EOV_Program_Logic_Rel_21_Mar72.pdf||File Number S360-30
Order Number GY28-6609-6
OS OPEN/CLOSE/EOV Logic
Program Number 360S-DM-50B
This publication, intended for system programmers and people who want
to understand the Open/Close/End-of-Volume (EOY) portion of the
operating system, describes the units of processing (functions) and units
of code (modules) of Open/Close/EOV.
Open opens a data set by linking system control blocks so that the access
methods can perform the input/output operations requested by the user.
EOV applies these linkages when the end of a volume of a multivolume
data set is reached and performs end-of-data processing. Close closes a
data set by restoring the system control blocks to the contents they had
before the data set was opened.
The book is divided into the following sections: Introduction, Method of