z/TPF Program Management - IBM

Use selective activate exits
Selective activate exits allow you to limit the use of an E-type loader loadset to a
specific ECB origin. An ECB origin can be a terminal address, communication line
number, port number, user ID, NCP ALS, NCP name, and others.
To use the selective activate function you must:
v Activate the selective activation function during system generation.
v Create an enable command.
v Create a disable command.
Activate the selective activation function
Create an enable command
You can activate the selective activation function in the CONFIG macro or by using
the ZSYSG command. When activated, selected ECBs can enter the programs and
files in a selectively activated loadset. Otherwise, no ECBs can enter the programs
and files in a selectively activated loadset. See z/TPF Operations for more
information about ZSYSG.
To enable loadsets for specific ECB origins, create a command that builds two
core-resident structures; a selective activation table and a selective activation index.
The selective activation table should contain loadset names and selective activation
numbers. The selective activation index should contain the ECB origins and
pointers to the loadset names. Entries should be added to these structures using a
user-defined enable message. To do this your command should do the following:
1. Add the ECB origin to the selective activation index.
2. If the loadset name is already in the selective activation table, update the index.
3. If the loadset name is not in the selective activation table, add the entry and call
the selective activate utility (COLW) to set the activation number. Update the
index.
Note: COLW returns an activation number of zero if the loadset has not been
selectively activated.
4. Update the file resident structure (if one exists) to allow enable requests to
survive an IPL.
Figure 10 shows an example of a selective activation table. Figure 11 on page 92
shows an example of a selective activation index.
Loadset Name Selective Activation Number
------------ ---------------------------
Joseph 0
Sally 4
Fred1 8
Figure 10. Selective activation table example
Note: In Figure 10, Joseph was enabled to be used from an ECB origin, but is not
yet activated selectively. Loadsets Sally and Fred1 were selectively activated
and were assigned activation numbers 4 and 8, respectively.
© Copyright IBM Corp. 2005, 2012 91