TU macro interface

EXCALL – exit call for TU programs (O type)

The EXCALL macro can be used from within TU programs to call exit routine 000.

[name] EXCALL

 

The contents of TU registers 0 and 15 are destroyed.

Systems support is responsible for deciding which parameters are passed on to exit routine 000 in register 1, the decision being arrived at in consultation with the caller. The information in register 1 is passed to the TPR PCB from the TU PCB.

The parameters transferred must be validated by the exit routine ($HVAL, $VALID). Care must be taken that these parameters can be accessed.

Otherwise exit routine 000 is governed by the same programming rules as all the other exit routines.