XBT_PUBLIC(void) TRACE_host_variable_set (const char *host, const char *variable, double value);
XBT_PUBLIC(void) TRACE_host_variable_add (const char *host, const char *variable, double value);
XBT_PUBLIC(void) TRACE_host_variable_sub (const char *host, const char *variable, double value);
XBT_PUBLIC(void) TRACE_host_variable_set (const char *host, const char *variable, double value);
XBT_PUBLIC(void) TRACE_host_variable_add (const char *host, const char *variable, double value);
XBT_PUBLIC(void) TRACE_host_variable_sub (const char *host, const char *variable, double value);