What is Roscoe BTSO Facility?

Products

• Roscoe

Issue/Introduction

WHAT IS BTSO

 

Resolution

BTSO is an acronym for Batch Time Sharing Option. This facility permits users to execute a broad spectrum of purchased and/or site-written batch interactive applications. Unlike ETSO, which executes applications in the Advantage CA-Roscoe address space and has to monitor or supervise the entire execution, BTSO "attaches" a new address space for the application and allows the program to execute on it's own in a separate address space. Advantage CA-Roscoe intercepts only terminal reads and writes (TGETS AND TPUTS), so it can pass information back and fourth between the user and the application.

BTSO CONTROL BLOCKS

BTSO relies on three control blocks to pass the information back between ROSCOE and the user.

ETSM is the main BTSO control block. It resides in CSA and contains information such as the maximum users and the timeout value. It also contains a pointer to each ETSU or user control block.

ETSU or BTSO user control block resides in CSA, contains the job name, program, and pointers to the ETSB control blocks.

ETSB control block points to the buffers that pass TPUTS and TGETS back and fourth between the batch address space and Roscoe. The ETSB are present only while a TPUT or TGET is active. The number of ETSBs will grow and shrink according to the TPUT and TGET activity.

BTSO SETUP

1. BTSO must be defined to ETSO via the EPL entry. See below for the sample:
   
   RTBETSO 5 2 4 96 3 72 5 3 N Y CA--ROSCOE BTSO

• The BTSO job may be started either as a JCL stream or as a started task. It is essential that an initiator be available for every BTSO user. To this end, we suggest that you set aside a number of initiators in a specific class just for BTSO. You should then set the BTSO MAXUSERS= parameter to this value.
  
  Remember that a process executing in a BTSO address space will be authorized only if all of the three following requirements are met:
  1. The program is link-edited with the APF authorization attribute (AC=1).
  2. The program resides in an APF authorized library.
  3. The program is included in CA-Roscoe BTSO table RTBATABL.

CALLING A BTSO JOB

RTBETSO expects one of two different kinds of inputs:

1. JCL statements
   
   The JCL statements for the application must contain one and only one jobcard and one or more EXEC statements. However, there can be as many DD statements as necessary.

• Parameter statements to indicate that the job is to be a started task
  
  Required parameters are:
  PGM=
  PROC=
  PROCPARM=
  
  Where:
  PGM= parameter specifies the name of the program to be executed.
  PROC= parameter specifies the name of the proc to be started.
  PROCPARM= parameter allows the user to specify additional parameters to the proc.

Notes:

• The program name may contain the following to specify the type of program to be executed:
  Value Meaning
  (CP) Command processor
  (P) Problem program
  (SCP) Command processor with synchronized TPUTS
• PROC must include the parameter "BTSOCNTL".
• RTBETSO changes the program name being executed to RTBATCH.
• The JCL is submitted through the internal reader where appropriate SUBEXIT calls are made.
• TERMINAL DATASETS MUST BE DEFINED AS "SYSOUT=(,TERM)"

STATUS of BTSO

The RTB monitor will allow users to view the status of BTSO. To activate the RTB monitor, you must first include a RUN=RTB statement in the Advantage CA-Roscoe SYSIN stream.
The RTB monitor provides you with:
ETSM address
MAXUSERS= value
TIMEOUT= value
Current number of users
Maximum number of users since last IPL
Displays of the currently active programs executing under BTSO