How these tests work:

Dejagnu finds all *.c files, compiles them and runs them in a temporary 
directory  while running the systemtap script sys.stp.  

If you need to know why a test is failing you can look in the test log, or
> gcc -o testname testname.c
> test-debug.tcl testname 


HOW TO WRITE TESTS

1. write a test case C file using some system calls.

2. After each system call, put a comment on the next line starting with "//"
The comment should have the expected output.  Where an arbitrary number
is expected, put "NNNN" (for decimal) or "XXXX" (for hex). Or you can
just write regular expressions. The "NNNN" and "XXXX" are just shorthand to
aid readability and are converted to regular expressions in test.tcl.

Normally opening and closing parentheses ('(' and ')') get quoted.  If
you want unquoted parentheses, use '[[[[' (for '(') or ']]]]' (for ')').

3. Somewhere is your test program puts a comment line like this:
/* COVERAGE: syscall1 syscall2 ... */
where you list the systemcalls that are tested.  Then you can run 
coverage.tcl and get a coverage report.

You probably want to write your test case without the comments first. Make
sure it compiles and works as expected. Then try it with 
"stap sys.stp -c ./testname" or test-debug.tcl to see the output.

IMPORTANT: Note that the test scripts create a temporary directory for each 
test program. Each program will run in an empty directory.