The dialog-supplied routines are invoked by using standard linkage.
Addresses must be 31-bit addresses, and the addressing mode (AMODE)
of the routines must be AMODE=31.
A BRIF read routine must have an assembler interface to be used
in a call to BRIF.
The dialog-supplied read and command processing routines are called
directly by ISPF at the same task level (TCB) that displays the ISPF
screens. If you need to ensure that your program runs at the same
task level as the routines, use the SELECT PGM( ) service to start
your program. This may be a factor if your program expects to create
or share data spaces or other task-specific resources between the
main program and the read, write, or command routines.
Note: - The dialog-supplied routines and the read and command exits can
be written in languages that use the Language Environment® runtime
environment, provided the runtime environment has the Language Environment TRAP(ON)
option set. However, a mixture of Language Environment-conforming
main dialog code and service routine code is not supported. Dialogs
and service routines must either all be Language Environment-conforming
or all be Language Environment-nonconforming.
- Language Environment applications
that use the ISPF BRIF or EDIF service must use the Language Environment OS_UPSTACK
option. For ISPF to invoke the user routines with a valid LE dynamic
save area, the Language
Environment application must issue a CONTROL LE ON service
request before each BRIF or EDIF service request and a CONTROL
LE OFF service request after each BRIF or EDIF service request.