use `h2o_configurator_errprintf` instead of `fprintf`
@@ -1233,7 +1233,7 @@ static int on_config_num_threads(h2o_configurator_command_t *cmd, h2o_configurat
conf.thread_map.entries[conf.thread_map.size++] = -1;
} else if (node->type == YOML_TYPE_SEQUENCE) {
#ifndef H2O_HAS_PTHREAD_SETAFFINITY_NP
- fprintf(stderr, "[error] Can't handle a CPU list, this platform doesn't support `pthread_setaffinity_np`\n");
+ h2o_configurator_errprintf(cmd, node, "[error] Can't handle a CPU list, this platform doesn't support `pthread_setaffinity_np`\n");
return -1;
#endif
/* a sequence is treated as a list of CPUs to bind to, one per thread to instantiate */
