const char *cl_retdbdir(void); int cl_load(const char *path, struct cl_engine *engine, unsigned int *signo, unsigned int options);
cl_retdbdir() returns the default (hardcoded) path to the directory
    with ClamAV databases.
    cl_load() loads a single database file or all databases from a
    given directory (when path points to a directory). The second
    argument is used for passing in the pointer to the engine that should
    be previously allocated with cl_engine_new(). A number of loaded
    signatures will be added to signo 10. The last argument can
    pass the following flags:
    
cl_load() returns CL_SUCCESS on success and another code on
    failure.
    
	    ...
	    struct cl_engine *engine;
	    unsigned int sigs = 0;
	    int ret;
	if((ret = cl_init()) != CL_SUCCESS) {
	    printf("cl_init() error: %s\n", cl_strerror(ret));
	    return 1;
	}
	if(!(engine = cl_engine_new())) {
	    printf("Can't create new engine\n");
	    return 1;
	}
	ret = cl_load(cl_retdbdir(), engine, &sigs, CL_DB_STDOPT);