--- /dev/null
+.\" $OpenBSD: X509_get_signature_nid.3,v 1.1 2018/02/14 18:50:47 schwarze Exp $
+.\" selective merge up to:
+.\" OpenSSL man3/X509_get0_signature 2f7a2520 Apr 25 17:28:08 2017 +0100
+.\"
+.\" This file was written by Dr. Stephen Henson <steve@openssl.org>.
+.\" Copyright (c) 2015 The OpenSSL Project. All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\"
+.\" 1. Redistributions of source code must retain the above copyright
+.\" notice, this list of conditions and the following disclaimer.
+.\"
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\" notice, this list of conditions and the following disclaimer in
+.\" the documentation and/or other materials provided with the
+.\" distribution.
+.\"
+.\" 3. All advertising materials mentioning features or use of this
+.\" software must display the following acknowledgment:
+.\" "This product includes software developed by the OpenSSL Project
+.\" for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+.\"
+.\" 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+.\" endorse or promote products derived from this software without
+.\" prior written permission. For written permission, please contact
+.\" openssl-core@openssl.org.
+.\"
+.\" 5. Products derived from this software may not be called "OpenSSL"
+.\" nor may "OpenSSL" appear in their names without prior written
+.\" permission of the OpenSSL Project.
+.\"
+.\" 6. Redistributions of any form whatsoever must retain the following
+.\" acknowledgment:
+.\" "This product includes software developed by the OpenSSL Project
+.\" for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+.\" EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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+.\"
+.Dd $Mdocdate: February 14 2018 $
+.Dt X509_GET_SIGNATURE_NID 3
+.Os
+.Sh NAME
+.Nm X509_get_signature_nid
+.Nd signature information
+.Sh SYNOPSIS
+.In openssl/x509.h
+.Ft int
+.Fo X509_get_signature_nid
+.Fa "const X509 *x"
+.Fc
+.Sh DESCRIPTION
+.Fn X509_get_signature_nid
+returns the NID corresponding to the signature algorithm of
+.Fa x .
+.Sh SEE ALSO
+.Xr OBJ_obj2nid 3 ,
+.Xr X509_get_pubkey 3 ,
+.Xr X509_get_subject_name 3 ,
+.Xr X509_get_version 3 ,
+.Xr X509_new 3 ,
+.Xr X509_sign 3 ,
+.Xr X509_verify_cert 3
+.Sh HISTORY
+.Fn X509_get_signature_nid
+first appeared in OpenSSL 1.0.2.