CA Dynam for VSE User Guide

Tape File Management Utilities
The tape should not be subsequently rewound by the user program.
TDYNASN normally reads input from SYSIPT. When the OPEN function is used
for SYSIPT, TDYNASN must be directed to read its input from SYSRDR. The
use of UPSI 001 reassigns SYSIPT and causes the TDYNASN OPEN function to
read its input from SYSRDR instead.
CLOSE Command
The CLOSE command causes the CA Dynam Catalog to be updated but does
not actually close the file; it does not write an EOF1 record and tape mark.
This can be done with an MTC job control command; the TDYNASN CLOSE
function does not release the assignment.
Note: The CLOSE command has to access the original label (TLBL) that was
opened, generally by the OPEN command. If this is not done, the CLOSE will
be unsuccessful.
Example:
// JOB CREATE SYSPCH TAPE
// TLBL FILEA,'DSN,P'
// EXEC TDYNASN
OPEN FILEA,SYSPCH,OUTPUT
/*
// EXEC ASSEMBLY
ASSEMBLY PROGRAM INPUT
/*
// EXEC TDYNASN
CLOSE FILEA,SYSPCH,OUTPUT
/*
// MTC REW,SYSPCH (The close only Catalogs the data set.)
/&
// JOB READ SYSPCH TAPE
// TLBL FILEA,'DSN'
// UPSI 001 READ FROM SYSRDR
// EXEC TDYNASN
OPEN FILEA,SYSIPT,INPUT
/*
// EXEC LIBR
/*
// MTC RUN,SYSIPT
/&
This example uses TDYNASN to create a SYSPCH tape, then reads it as
SYSIPT.
Note: Dynamic LUB allocation must be bypassed for the SYSPCH tape.
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