XBT_PUBLIC int sg_exec_test(sg_exec_t exec);
XBT_PUBLIC sg_error_t sg_exec_wait(sg_exec_t exec);
XBT_PUBLIC sg_error_t sg_exec_wait_for(sg_exec_t exec, double timeout);
XBT_PUBLIC int sg_exec_test(sg_exec_t exec);
XBT_PUBLIC sg_error_t sg_exec_wait(sg_exec_t exec);
XBT_PUBLIC sg_error_t sg_exec_wait_for(sg_exec_t exec, double timeout);