diff --git a/libc/Android.bp b/libc/Android.bp
index 5bd00c8..8717f7b 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -8,7 +8,6 @@
     "bionic/fts.c",
     "bionic/initgroups.c",
     "bionic/isatty.c",
-    "bionic/pututline.c",
     "bionic/sched_cpualloc.c",
     "bionic/sched_cpucount.c",
     "stdio/fmemopen.cpp",
@@ -391,7 +390,6 @@
         "upstream-netbsd/lib/libc/gen/nice.c",
         "upstream-netbsd/lib/libc/gen/psignal.c",
         "upstream-netbsd/lib/libc/gen/utime.c",
-        "upstream-netbsd/lib/libc/gen/utmp.c",
         "upstream-netbsd/lib/libc/inet/nsap_addr.c",
         "upstream-netbsd/lib/libc/regex/regcomp.c",
         "upstream-netbsd/lib/libc/regex/regerror.c",
@@ -1154,6 +1152,7 @@
         "bionic/umount.cpp",
         "bionic/unlink.cpp",
         "bionic/usleep.cpp",
+        "bionic/utmp.cpp",
         "bionic/wait.cpp",
         "bionic/wchar.cpp",
         "bionic/wchar_l.cpp",
diff --git a/libc/NOTICE b/libc/NOTICE
index 7f2e8b0..764fd7b 100644
--- a/libc/NOTICE
+++ b/libc/NOTICE
@@ -3456,35 +3456,6 @@
 
 -------------------------------------------------------------------
 
-Copyright (c) 2002 The NetBSD Foundation, Inc.
-All rights reserved.
-
-This code is derived from software contributed to The NetBSD Foundation
-by Christos Zoulas.
-
-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.
-
-THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
-``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
-TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
-BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGE.
-
--------------------------------------------------------------------
-
 Copyright (c) 2002 Tim J. Robbins
 All rights reserved.
 
diff --git a/libc/bionic/pututline.c b/libc/bionic/utmp.cpp
similarity index 64%
rename from libc/bionic/pututline.c
rename to libc/bionic/utmp.cpp
index 8cbf470..aa00cd5 100644
--- a/libc/bionic/pututline.c
+++ b/libc/bionic/utmp.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008 The Android Open Source Project
+ * Copyright (C) 2020 The Android Open Source Project
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -25,40 +25,24 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
-#include <string.h>
-#include <stdio.h>
+
 #include <utmp.h>
 
+#include <errno.h>
 
-void pututline(struct utmp* utmp)
-{
-    FILE* f;
-    struct utmp u;
-    long i;
+void endutent() {}
 
-    if (!(f = fopen(_PATH_UTMP, "w+e")))
-        return;
+void setutent() {}
 
-    while (fread(&u, sizeof(struct utmp), 1, f) == 1)
-    {
-        if (!strncmp(utmp->ut_line, u.ut_line, sizeof(u.ut_line) -1))
-        {
-            if ((i = ftell(f)) < 0)
-                goto ret;
-            if (fseek(f, i - sizeof(struct utmp), SEEK_SET) < 0)
-                goto ret;
-            fwrite(utmp, sizeof(struct utmp), 1, f);
-            goto ret;
-        }
-    }
+utmp* getutent() {
+  return nullptr;
+}
 
+utmp* pututline(const utmp*) {
+  return nullptr;
+}
 
-    fclose(f);
-
-    if (!(f = fopen(_PATH_UTMP, "w+e")))
-        return;
-    fwrite(utmp, sizeof(struct utmp), 1, f);
-
-ret:
-    fclose(f);
+int utmpname(const char*) {
+  errno = ENOTSUP;
+  return -1;
 }
diff --git a/libc/include/utmp.h b/libc/include/utmp.h
index 6a52511..cb72ce2 100644
--- a/libc/include/utmp.h
+++ b/libc/include/utmp.h
@@ -25,8 +25,13 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
-#ifndef _UTMP_H_
-#define _UTMP_H_
+
+#pragma once
+
+/**
+ * @file utmp.h
+ * @brief POSIX login records.
+ */
 
 #include <sys/cdefs.h>
 #include <sys/types.h>
@@ -57,52 +62,71 @@
 #define DEAD_PROCESS  8
 #define ACCOUNTING    9
 
-struct lastlog
-{
-    time_t ll_time;
-    char ll_line[UT_LINESIZE];
-    char ll_host[UT_HOSTSIZE];
+struct lastlog {
+  time_t ll_time;
+  char ll_line[UT_LINESIZE];
+  char ll_host[UT_HOSTSIZE];
 };
 
-struct exit_status
-{
-    short int e_termination;
-    short int e_exit;
+struct exit_status {
+  short int e_termination;
+  short int e_exit;
 };
 
+struct utmp {
+  short int ut_type;
+  pid_t ut_pid;
+  char ut_line[UT_LINESIZE];
+  char ut_id[4];
+  char ut_user[UT_NAMESIZE];
+  char ut_host[UT_HOSTSIZE];
 
-struct utmp
-{
-    short int ut_type;
-    pid_t ut_pid;
-    char ut_line[UT_LINESIZE];
-    char ut_id[4];
-    char ut_user[UT_NAMESIZE];
-    char ut_host[UT_HOSTSIZE];
+  struct exit_status ut_exit;
 
-    struct exit_status ut_exit;
+  long int ut_session;
+  struct timeval ut_tv;
 
-    long int ut_session;
-    struct timeval ut_tv;
-
-    int32_t ut_addr_v6[4];
-    char unsed[20];
+  int32_t ut_addr_v6[4];
+  char unused[20];
 };
 
-
 #define ut_name ut_user
 #define ut_time ut_tv.tv_sec
 #define ut_addr ut_addr_v6[0]
 
 __BEGIN_DECLS
 
+/**
+ * Does nothing.
+ */
 int utmpname(const char* __path);
+/**
+ * Does nothing.
+ */
 void setutent(void);
+/**
+ * Does nothing.
+ */
 struct utmp* getutent(void);
+/**
+ * Does nothing.
+ */
+struct utmp* pututline(const struct utmp* __entry);
+/**
+ * Does nothing.
+ */
 void endutent(void);
 
+/**
+ * [login_tty(3)](https://www.man7.org/linux/man-pages/man3/login_tty.3.html)
+ * prepares for login on the given file descriptor.
+ *
+ * See also forkpty() which combines openpty(), fork(), and login_tty().
+ *
+ * Returns 0 on success and returns -1 and sets `errno` on failure.
+ *
+ * Available since API level 23.
+ */
 int login_tty(int __fd) __INTRODUCED_IN(23);
 
 __END_DECLS
-
-#endif /* _UTMP_H_ */
diff --git a/libc/upstream-netbsd/lib/libc/gen/utmp.c b/libc/upstream-netbsd/lib/libc/gen/utmp.c
deleted file mode 100644
index 9fb0799..0000000
--- a/libc/upstream-netbsd/lib/libc/gen/utmp.c
+++ /dev/null
@@ -1,106 +0,0 @@
-/*	$NetBSD: utmp.c,v 1.10 2011/10/15 23:00:02 christos Exp $	 */
-
-/*-
- * Copyright (c) 2002 The NetBSD Foundation, Inc.
- * All rights reserved.
- *
- * This code is derived from software contributed to The NetBSD Foundation
- * by Christos Zoulas.
- *
- * 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.
- *
- * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
- * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
- * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-#include <sys/cdefs.h>
-
-#if defined(LIBC_SCCS) && !defined(lint)
-__RCSID("$NetBSD: utmp.c,v 1.10 2011/10/15 23:00:02 christos Exp $");
-#endif /* LIBC_SCCS and not lint */
-
-#include "namespace.h"
-#include <sys/types.h>
-#include <sys/param.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-#include <utmp.h>
-#include <sys/stat.h>
-
-static struct utmp utmp;
-static FILE *ut;
-static char utfile[MAXPATHLEN] = _PATH_UTMP;
-
-void
-setutent(void)
-{
-	if (ut == NULL)
-		return;
-	(void)fseeko(ut, (off_t)0, SEEK_SET);
-}
-
-struct utmp *
-getutent(void)
-{
-	if (ut == NULL) {
-		struct stat st;
-		off_t numentries;
-		if ((ut = fopen(utfile, "re")) == NULL)
-			return NULL;
-		if (fstat(fileno(ut), &st) == -1)
-			goto out;
-		/*
-		 * If we have a an old version utmp file bail.
-		 */
-		numentries = st.st_size / sizeof(utmp);
-		if ((off_t)(numentries * sizeof(utmp)) != st.st_size)
-			goto out;
-	}
-	if (fread(&utmp, sizeof(utmp), 1, ut) == 1)
-		return &utmp;
-out:
-	(void)fclose(ut);
-	return NULL;
-}
-
-void
-endutent(void)
-{
-	if (ut != NULL) {
-		(void)fclose(ut);
-		ut = NULL;
-	}
-}
-
-int
-utmpname(const char *fname)
-{
-	size_t len = strlen(fname);
-
-	if (len >= sizeof(utfile))
-		return 0;
-
-	/* must not end in x! */
-	if (fname[len - 1] == 'x')
-		return 0;
-
-	(void)strlcpy(utfile, fname, sizeof(utfile));
-	endutent();
-	return 1;
-}