Runtime environment, environment variables on Windows systems

The environment variables listed in the table on "Runtime environment, linking, starting" are used for controlling CPI-C applications.

The path name can be given with spaces in the UPICTRACE variable. If spaces are used, then the path name must be enclosed in double quotes. Double quotes can also be used if there are no spaces in the path name.

There are user variables that apply only for the current user ID, and there are system variables that apply for all users. You must set system variables if you want to run a UPIC application as a service (a service runs without a user environment).

CPI-C program resources

• One file descriptor is reserved permanently for the trace file.

• If information is written to the log file, a file descriptor is used only during the write operation.

• Reading from the upicfile only requires a file descriptor during the Enable_UTM_UPIC call.

• Other resources are also used by the transport system.