The Clean-Up Utility in FronTier

The goal of a cleanup utility ("util/cleanup.c") is to terminate a run in a useful manner. Many different problems can occur as, illustrated in the table below, which some form of handling is very useful.

A perfect run	error = 0
The developer wants it: a case arises which should not arise or for which there is as yet no code.	error = ERROR = -1
A casualty of a computational error:
Floating point exception (for instance division by zero)	error = SIGFPE = 8
Bus Error (for instance: function argument mismatch)	error = SIGBUS = 10
Segmentation Violation (for instance: undeclared pointer)	error = SIGSEGV = 11
...................	error = .....
The user kills it (for instance "control C" or "kill")	error = SIGQUIT or SIGKILL
Other: machine malfunction or hard kill ("kill -9")	NO CLEANUP

In all but the other case, FronTier will call the function clean_up:

EXPORT	void clean_up(int error)

which will:

Print the debug list of FronTier
Do the FronTier printout of the last time-step (very useful for restart).
Print the storage holdings of FronTier's own memory allocator.

The function cleanup gets called in two different ways:

Directly by the user: error = 0 (run is OK) or error = ERROR and interpreted as the user's will to stop the run right now. For the definition of the macro ERROR (=-1) see "/util/cdecs.h".
By the system. The C-language provides for a redirection to an error-handler of errors which are caught by the system (as defined in "/usr/include/sys/signal.h"). What cleanup precisely does for each of the system errors is defined in the function print_final_storage_and_error(int error) in /util/cleanup.c.

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Authors: Folkert Tangerman
Last revision: April 10, 1997

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