7. The 32-bit Windows version of C$CHAIN has a side-effect that you should be aware of. 32-bit Windows does not provide a mechanism for "chaining" programs. Instead, we initiate the chained-to program as an independent program and then halt the chained-from program.
Although this has the correct effect, 32-bit Windows causes the "active" program to shift from the chained-to program to some other program when the chained-from program halts. It is impossible for the runtime to determine which program will be selected by 32-bit Windows as the "active" one.
The net effect is that the chained-to program pops up, but then becomes inactive and must be reactivated with either the mouse or the keyboard in order for the user to enter data. 32-bit Windows does not provide any mechanism for suggesting which program to activate when a program halts.