libval(3) on Linux
The text d25300ede897, as Debian 8 (Jessie) shipped it.
manage validator context val_context_setqflags() - manage validator context flags val_resolve_and_check(), val_free_result_chain() - query and validate answers from a DNS name server val_istrusted() - check if status value corresponds to that of a trustworthy answer val_isvalidated() - check if status value represents an answer that cryptographically chains down from a configured trust anchor val_does_not_exist() - check if status value represents one of the non-existence types p_val_status(), p_ac_status(), p_val_error() - display validation status, authentication chain status and error information val_log_add_optarg - control log message verbosity and output location