Groundwork towards making the Libcore.os functionality public. Change-Id: Ie700aa16d91fba53fc5eb2555829cb74d84b12ad

diff --git a/dalvik/src/main/java/dalvik/system/DexFile.java b/dalvik/src/main/java/dalvik/system/DexFile.java
index d0bfe5f..f1a8013 100644
--- a/dalvik/src/main/java/dalvik/system/DexFile.java
+++ b/dalvik/src/main/java/dalvik/system/DexFile.java

@@ -16,15 +16,15 @@
 
 package dalvik.system;
 
+import android.system.ErrnoException;
+import android.system.StructStat;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Enumeration;
 import java.util.List;
-import libcore.io.ErrnoException;
 import libcore.io.Libcore;
-import libcore.io.StructStat;
 
 /**
  * Manipulates DEX files. The class is similar in principle to

diff --git a/dalvik/src/main/java/dalvik/system/DexPathList.java b/dalvik/src/main/java/dalvik/system/DexPathList.java
index f3bee10..e364e40 100644
--- a/dalvik/src/main/java/dalvik/system/DexPathList.java
+++ b/dalvik/src/main/java/dalvik/system/DexPathList.java

@@ -16,6 +16,8 @@
 
 package dalvik.system;
 
+import android.system.ErrnoException;
+import android.system.StructStat;
 import java.io.File;
 import java.io.IOException;
 import java.net.MalformedURLException;
@@ -26,11 +28,9 @@
 import java.util.Enumeration;
 import java.util.List;
 import java.util.zip.ZipFile;
-import libcore.io.ErrnoException;
 import libcore.io.IoUtils;
 import libcore.io.Libcore;
-import libcore.io.StructStat;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * A pair of lists of entries, associated with a {@code ClassLoader}.

diff --git a/luni/src/main/java/libcore/util/MutableChar.java b/luni/src/main/java/android/system/ErrnoException.java
similarity index 65%
copy from luni/src/main/java/libcore/util/MutableChar.java
copy to luni/src/main/java/android/system/ErrnoException.java
index 1cafc3c..5114bec 100644
--- a/luni/src/main/java/libcore/util/MutableChar.java
+++ b/luni/src/main/java/android/system/ErrnoException.java

@@ -14,12 +14,17 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.system;
 
-public final class MutableChar {
-    public char value;
+/**
+ * @hide
+ */
+public final class ErrnoException extends libcore.io.ErrnoException {
+  public ErrnoException(String functionName, int errno) {
+    super(functionName, errno);
+  }
 
-    public MutableChar(char value) {
-        this.value = value;
-    }
+  public ErrnoException(String functionName, int errno, Throwable cause) {
+    super(functionName, errno, cause);
+  }
 }

diff --git a/luni/src/main/java/android/system/GaiException.java b/luni/src/main/java/android/system/GaiException.java
new file mode 100644
index 0000000..803fc29
--- /dev/null
+++ b/luni/src/main/java/android/system/GaiException.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.system;
+
+import java.net.UnknownHostException;
+import libcore.io.Libcore;
+
+/**
+ * An unchecked exception thrown when {@code getaddrinfo} or {@code getnameinfo} fails.
+ * This exception contains the native {@link #error} value, should sophisticated
+ * callers need to adjust their behavior based on the exact failure.
+ *
+ * @hide
+ */
+public final class GaiException extends RuntimeException {
+  private final String functionName;
+
+  /**
+   * The native error value, for comparison with the {@code GAI_} constants in {@link OsConstants}.
+   */
+  public final int error;
+
+  public GaiException(String functionName, int error) {
+    this.functionName = functionName;
+    this.error = error;
+  }
+
+  public GaiException(String functionName, int error, Throwable cause) {
+    super(cause);
+    this.functionName = functionName;
+    this.error = error;
+  }
+
+  /**
+   * Converts the stashed function name and error value to a human-readable string.
+   * We do this here rather than in the constructor so that callers only pay for
+   * this if they need it.
+   */
+  @Override public String getMessage() {
+    String gaiName = OsConstants.gaiName(error);
+    if (gaiName == null) {
+      gaiName = "GAI_ error " + error;
+    }
+    String description = Libcore.os.gai_strerror(error);
+    return functionName + " failed: " + gaiName + " (" + description + ")";
+  }
+
+  public UnknownHostException rethrowAsUnknownHostException(String detailMessage) throws UnknownHostException {
+    UnknownHostException newException = new UnknownHostException(detailMessage);
+    newException.initCause(this);
+    throw newException;
+  }
+
+  public UnknownHostException rethrowAsUnknownHostException() throws UnknownHostException {
+    throw rethrowAsUnknownHostException(getMessage());
+  }
+}

diff --git a/luni/src/main/java/android/system/Os.java b/luni/src/main/java/android/system/Os.java
new file mode 100644
index 0000000..0ca22a9
--- /dev/null
+++ b/luni/src/main/java/android/system/Os.java

@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.system;
+
+import android.system.ErrnoException;
+import android.system.GaiException;
+import android.system.StructAddrinfo;
+import android.system.StructFlock;
+import android.system.StructGroupReq;
+import android.system.StructGroupSourceReq;
+import android.system.StructLinger;
+import android.system.StructPasswd;
+import android.system.StructPollfd;
+import android.system.StructStat;
+import android.system.StructStatVfs;
+import android.system.StructTimeval;
+import android.system.StructUcred;
+import android.system.StructUtsname;
+import android.util.MutableInt;
+import android.util.MutableLong;
+import java.io.FileDescriptor;
+import java.io.InterruptedIOException;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+import java.net.SocketException;
+import java.nio.ByteBuffer;
+import libcore.io.Libcore;
+
+/**
+ * @hide
+ */
+public final class Os {
+  private Os() {}
+
+  public static FileDescriptor accept(FileDescriptor fd, InetSocketAddress peerAddress) throws ErrnoException, SocketException { return Libcore.os.accept(fd, peerAddress); }
+  public static boolean access(String path, int mode) throws ErrnoException { return Libcore.os.access(path, mode); }
+  public static void bind(FileDescriptor fd, InetAddress address, int port) throws ErrnoException, SocketException { Libcore.os.bind(fd, address, port); }
+  public static void chmod(String path, int mode) throws ErrnoException { Libcore.os.chmod(path, mode); }
+  public static void chown(String path, int uid, int gid) throws ErrnoException { Libcore.os.chown(path, uid, gid); }
+  public static void close(FileDescriptor fd) throws ErrnoException { Libcore.os.close(fd); }
+  public static void connect(FileDescriptor fd, InetAddress address, int port) throws ErrnoException, SocketException { Libcore.os.connect(fd, address, port); }
+  public static FileDescriptor dup(FileDescriptor oldFd) throws ErrnoException { return Libcore.os.dup(oldFd); }
+  public static FileDescriptor dup2(FileDescriptor oldFd, int newFd) throws ErrnoException { return Libcore.os.dup2(oldFd, newFd); }
+  public static String[] environ() { return Libcore.os.environ(); }
+  public static void execv(String filename, String[] argv) throws ErrnoException { Libcore.os.execv(filename, argv); }
+  public static void execve(String filename, String[] argv, String[] envp) throws ErrnoException { Libcore.os.execve(filename, argv, envp); }
+  public static void fchmod(FileDescriptor fd, int mode) throws ErrnoException { Libcore.os.fchmod(fd, mode); }
+  public static void fchown(FileDescriptor fd, int uid, int gid) throws ErrnoException { Libcore.os.fchown(fd, uid, gid); }
+  public static int fcntlVoid(FileDescriptor fd, int cmd) throws ErrnoException { return Libcore.os.fcntlVoid(fd, cmd); }
+  public static int fcntlLong(FileDescriptor fd, int cmd, long arg) throws ErrnoException { return Libcore.os.fcntlLong(fd, cmd, arg); }
+  public static int fcntlFlock(FileDescriptor fd, int cmd, StructFlock arg) throws ErrnoException { return Libcore.os.fcntlFlock(fd, cmd, arg); }
+  public static void fdatasync(FileDescriptor fd) throws ErrnoException { Libcore.os.fdatasync(fd); }
+  public static StructStat fstat(FileDescriptor fd) throws ErrnoException { return Libcore.os.fstat(fd); }
+  public static StructStatVfs fstatvfs(FileDescriptor fd) throws ErrnoException { return Libcore.os.fstatvfs(fd); }
+  public static void fsync(FileDescriptor fd) throws ErrnoException { Libcore.os.fsync(fd); }
+  public static void ftruncate(FileDescriptor fd, long length) throws ErrnoException { Libcore.os.ftruncate(fd, length); }
+  public static String gai_strerror(int error) { return Libcore.os.gai_strerror(error); }
+  public static InetAddress[] getaddrinfo(String node, StructAddrinfo hints) throws GaiException { return Libcore.os.getaddrinfo(node, hints); }
+  public static int getegid() { return Libcore.os.getegid(); }
+  public static int geteuid() { return Libcore.os.geteuid(); }
+  public static int getgid() { return Libcore.os.getgid(); }
+  public static String getenv(String name) { return Libcore.os.getenv(name); }
+  public static String getnameinfo(InetAddress address, int flags) throws GaiException { return Libcore.os.getnameinfo(address, flags); }
+  public static SocketAddress getpeername(FileDescriptor fd) throws ErrnoException { return Libcore.os.getpeername(fd); }
+  public static int getpid() { return Libcore.os.getpid(); }
+  public static int getppid() { return Libcore.os.getppid(); }
+  public static StructPasswd getpwnam(String name) throws ErrnoException { return Libcore.os.getpwnam(name); }
+  public static StructPasswd getpwuid(int uid) throws ErrnoException { return Libcore.os.getpwuid(uid); }
+  public static SocketAddress getsockname(FileDescriptor fd) throws ErrnoException { return Libcore.os.getsockname(fd); }
+  public static int getsockoptByte(FileDescriptor fd, int level, int option) throws ErrnoException { return Libcore.os.getsockoptByte(fd, level, option); }
+  public static InetAddress getsockoptInAddr(FileDescriptor fd, int level, int option) throws ErrnoException { return Libcore.os.getsockoptInAddr(fd, level, option); }
+  public static int getsockoptInt(FileDescriptor fd, int level, int option) throws ErrnoException { return Libcore.os.getsockoptInt(fd, level, option); }
+  public static StructLinger getsockoptLinger(FileDescriptor fd, int level, int option) throws ErrnoException { return Libcore.os.getsockoptLinger(fd, level, option); }
+  public static StructTimeval getsockoptTimeval(FileDescriptor fd, int level, int option) throws ErrnoException { return Libcore.os.getsockoptTimeval(fd, level, option); }
+  public static StructUcred getsockoptUcred(FileDescriptor fd, int level, int option) throws ErrnoException { return Libcore.os.getsockoptUcred(fd, level, option); }
+  public static int gettid() { return Libcore.os.gettid(); }
+  public static int getuid() { return Libcore.os.getuid(); }
+  public static String if_indextoname(int index) { return Libcore.os.if_indextoname(index); }
+  public static InetAddress inet_pton(int family, String address) { return Libcore.os.inet_pton(family, address); }
+  public static InetAddress ioctlInetAddress(FileDescriptor fd, int cmd, String interfaceName) throws ErrnoException { return Libcore.os.ioctlInetAddress(fd, cmd, interfaceName); }
+  public static int ioctlInt(FileDescriptor fd, int cmd, MutableInt arg) throws ErrnoException { return Libcore.os.ioctlInt(fd, cmd, arg); }
+  public static boolean isatty(FileDescriptor fd) { return Libcore.os.isatty(fd); }
+  public static void kill(int pid, int signal) throws ErrnoException { Libcore.os.kill(pid, signal); }
+  public static void lchown(String path, int uid, int gid) throws ErrnoException { Libcore.os.lchown(path, uid, gid); }
+  public static void listen(FileDescriptor fd, int backlog) throws ErrnoException { Libcore.os.listen(fd, backlog); }
+  public static long lseek(FileDescriptor fd, long offset, int whence) throws ErrnoException { return Libcore.os.lseek(fd, offset, whence); }
+  public static StructStat lstat(String path) throws ErrnoException { return Libcore.os.lstat(path); }
+  public static void mincore(long address, long byteCount, byte[] vector) throws ErrnoException { Libcore.os.mincore(address, byteCount, vector); }
+  public static void mkdir(String path, int mode) throws ErrnoException { Libcore.os.mkdir(path, mode); }
+  public static void mkfifo(String path, int mode) throws ErrnoException { Libcore.os.mkfifo(path, mode); }
+  public static void mlock(long address, long byteCount) throws ErrnoException { Libcore.os.mlock(address, byteCount); }
+  public static long mmap(long address, long byteCount, int prot, int flags, FileDescriptor fd, long offset) throws ErrnoException { return Libcore.os.mmap(address, byteCount, prot, flags, fd, offset); }
+  public static void msync(long address, long byteCount, int flags) throws ErrnoException { Libcore.os.msync(address, byteCount, flags); }
+  public static void munlock(long address, long byteCount) throws ErrnoException { Libcore.os.munlock(address, byteCount); }
+  public static void munmap(long address, long byteCount) throws ErrnoException { Libcore.os.munmap(address, byteCount); }
+  public static FileDescriptor open(String path, int flags, int mode) throws ErrnoException { return Libcore.os.open(path, flags, mode); }
+  public static FileDescriptor[] pipe() throws ErrnoException { return Libcore.os.pipe(); }
+  public static int poll(StructPollfd[] fds, int timeoutMs) throws ErrnoException { return Libcore.os.poll(fds, timeoutMs); }
+  public static void posix_fallocate(FileDescriptor fd, long offset, long length) throws ErrnoException { Libcore.os.posix_fallocate(fd, offset, length); }
+  public static int pread(FileDescriptor fd, ByteBuffer buffer, long offset) throws ErrnoException, InterruptedIOException { return Libcore.os.pread(fd, buffer, offset); }
+  public static int pread(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount, long offset) throws ErrnoException, InterruptedIOException { return Libcore.os.pread(fd, bytes, byteOffset, byteCount, offset); }
+  public static int pwrite(FileDescriptor fd, ByteBuffer buffer, long offset) throws ErrnoException, InterruptedIOException { return Libcore.os.pwrite(fd, buffer, offset); }
+  public static int pwrite(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount, long offset) throws ErrnoException, InterruptedIOException { return Libcore.os.pwrite(fd, bytes, byteOffset, byteCount, offset); }
+  public static int read(FileDescriptor fd, ByteBuffer buffer) throws ErrnoException, InterruptedIOException { return Libcore.os.read(fd, buffer); }
+  public static int read(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount) throws ErrnoException, InterruptedIOException { return Libcore.os.read(fd, bytes, byteOffset, byteCount); }
+  public static String readlink(String path) throws ErrnoException { return Libcore.os.readlink(path); }
+  public static int readv(FileDescriptor fd, Object[] buffers, int[] offsets, int[] byteCounts) throws ErrnoException, InterruptedIOException { return Libcore.os.readv(fd, buffers, offsets, byteCounts); }
+  public static int recvfrom(FileDescriptor fd, ByteBuffer buffer, int flags, InetSocketAddress srcAddress) throws ErrnoException, SocketException { return Libcore.os.recvfrom(fd, buffer, flags, srcAddress); }
+  public static int recvfrom(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount, int flags, InetSocketAddress srcAddress) throws ErrnoException, SocketException { return Libcore.os.recvfrom(fd, bytes, byteOffset, byteCount, flags, srcAddress); }
+  public static void remove(String path) throws ErrnoException { Libcore.os.remove(path); }
+  public static void rename(String oldPath, String newPath) throws ErrnoException { Libcore.os.rename(oldPath, newPath); }
+  public static long sendfile(FileDescriptor outFd, FileDescriptor inFd, MutableLong inOffset, long byteCount) throws ErrnoException { return Libcore.os.sendfile(outFd, inFd, inOffset, byteCount); }
+  public static int sendto(FileDescriptor fd, ByteBuffer buffer, int flags, InetAddress inetAddress, int port) throws ErrnoException, SocketException { return Libcore.os.sendto(fd, buffer, flags, inetAddress, port); }
+  public static int sendto(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount, int flags, InetAddress inetAddress, int port) throws ErrnoException, SocketException { return Libcore.os.sendto(fd, bytes, byteOffset, byteCount, flags, inetAddress, port); }
+  public static void setegid(int egid) throws ErrnoException { Libcore.os.setegid(egid); }
+  public static void setenv(String name, String value, boolean overwrite) throws ErrnoException { Libcore.os.setenv(name, value, overwrite); }
+  public static void seteuid(int euid) throws ErrnoException { Libcore.os.seteuid(euid); }
+  public static void setgid(int gid) throws ErrnoException { Libcore.os.setgid(gid); }
+  public static int setsid() throws ErrnoException { return Libcore.os.setsid(); }
+  public static void setsockoptByte(FileDescriptor fd, int level, int option, int value) throws ErrnoException { Libcore.os.setsockoptByte(fd, level, option, value); }
+  public static void setsockoptIfreq(FileDescriptor fd, int level, int option, String value) throws ErrnoException { Libcore.os.setsockoptIfreq(fd, level, option, value); }
+  public static void setsockoptInt(FileDescriptor fd, int level, int option, int value) throws ErrnoException { Libcore.os.setsockoptInt(fd, level, option, value); }
+  public static void setsockoptIpMreqn(FileDescriptor fd, int level, int option, int value) throws ErrnoException { Libcore.os.setsockoptIpMreqn(fd, level, option, value); }
+  public static void setsockoptGroupReq(FileDescriptor fd, int level, int option, StructGroupReq value) throws ErrnoException { Libcore.os.setsockoptGroupReq(fd, level, option, value); }
+  public static void setsockoptGroupSourceReq(FileDescriptor fd, int level, int option, StructGroupSourceReq value) throws ErrnoException { Libcore.os.setsockoptGroupSourceReq(fd, level, option, value); }
+  public static void setsockoptLinger(FileDescriptor fd, int level, int option, StructLinger value) throws ErrnoException { Libcore.os.setsockoptLinger(fd, level, option, value); }
+  public static void setsockoptTimeval(FileDescriptor fd, int level, int option, StructTimeval value) throws ErrnoException { Libcore.os.setsockoptTimeval(fd, level, option, value); }
+  public static void setuid(int uid) throws ErrnoException { Libcore.os.setuid(uid); }
+  public static void shutdown(FileDescriptor fd, int how) throws ErrnoException { Libcore.os.shutdown(fd, how); }
+  public static FileDescriptor socket(int domain, int type, int protocol) throws ErrnoException { return Libcore.os.socket(domain, type, protocol); }
+  public static void socketpair(int domain, int type, int protocol, FileDescriptor fd1, FileDescriptor fd2) throws ErrnoException { Libcore.os.socketpair(domain, type, protocol, fd1, fd2); }
+  public static StructStat stat(String path) throws ErrnoException { return Libcore.os.stat(path); }
+  public static StructStatVfs statvfs(String path) throws ErrnoException { return Libcore.os.statvfs(path); }
+  public static String strerror(int errno) { return Libcore.os.strerror(errno); }
+  public static String strsignal(int signal) { return Libcore.os.strsignal(signal); }
+  public static void symlink(String oldPath, String newPath) throws ErrnoException { Libcore.os.symlink(oldPath, newPath); }
+  public static long sysconf(int name) { return Libcore.os.sysconf(name); }
+  public static void tcdrain(FileDescriptor fd) throws ErrnoException { Libcore.os.tcdrain(fd); }
+  public static void tcsendbreak(FileDescriptor fd, int duration) throws ErrnoException { Libcore.os.tcsendbreak(fd, duration); }
+  public static int umask(int mask) { return Libcore.os.umask(mask); }
+  public static StructUtsname uname() { return Libcore.os.uname(); }
+  public static void unsetenv(String name) throws ErrnoException { Libcore.os.unsetenv(name); }
+  public static int waitpid(int pid, MutableInt status, int options) throws ErrnoException { return Libcore.os.waitpid(pid, status, options); }
+  public static int write(FileDescriptor fd, ByteBuffer buffer) throws ErrnoException, InterruptedIOException { return Libcore.os.write(fd, buffer); }
+  public static int write(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount) throws ErrnoException, InterruptedIOException { return Libcore.os.write(fd, bytes, byteOffset, byteCount); }
+  public static int writev(FileDescriptor fd, Object[] buffers, int[] offsets, int[] byteCounts) throws ErrnoException, InterruptedIOException { return Libcore.os.writev(fd, buffers, offsets, byteCounts); }
+}

diff --git a/luni/src/main/java/libcore/util/MutableChar.java b/luni/src/main/java/android/system/OsConstants.java
similarity index 80%
copy from luni/src/main/java/libcore/util/MutableChar.java
copy to luni/src/main/java/android/system/OsConstants.java
index 1cafc3c..f7e02af 100644
--- a/luni/src/main/java/libcore/util/MutableChar.java
+++ b/luni/src/main/java/android/system/OsConstants.java

@@ -14,12 +14,11 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.system;
 
-public final class MutableChar {
-    public char value;
-
-    public MutableChar(char value) {
-        this.value = value;
-    }
+/**
+ * @hide
+ */
+public final class OsConstants extends libcore.io.OsConstants {
+  private OsConstants() {}
 }

diff --git a/luni/src/main/java/libcore/io/StructAddrinfo.java b/luni/src/main/java/android/system/StructAddrinfo.java
similarity index 97%
rename from luni/src/main/java/libcore/io/StructAddrinfo.java
rename to luni/src/main/java/android/system/StructAddrinfo.java
index 8c8181d..9862190 100644
--- a/luni/src/main/java/libcore/io/StructAddrinfo.java
+++ b/luni/src/main/java/android/system/StructAddrinfo.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 import java.net.InetAddress;
 
@@ -23,6 +23,8 @@
  * <a href="http://pubs.opengroup.org/onlinepubs/009695399/basedefs/netdb.h.html">&lt;netdb.h&gt;</a>
  *
  * TODO: we currently only _take_ a StructAddrinfo; getaddrinfo returns an InetAddress[].
+ *
+ * @hide
  */
 public final class StructAddrinfo {
     /** Flags describing the kind of lookup to be done. (Such as AI_ADDRCONFIG.) */

diff --git a/luni/src/main/java/libcore/io/StructFlock.java b/luni/src/main/java/android/system/StructFlock.java
similarity index 97%
rename from luni/src/main/java/libcore/io/StructFlock.java
rename to luni/src/main/java/android/system/StructFlock.java
index 11c29df..4908420 100644
--- a/luni/src/main/java/libcore/io/StructFlock.java
+++ b/luni/src/main/java/android/system/StructFlock.java

@@ -14,12 +14,14 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 /**
  * Information returned/taken by fcntl(2) F_GETFL and F_SETFL. Corresponds to C's
  * {@code struct flock} from
  * <a href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/fcntl.h.html">&lt;fcntl.h&gt;</a>
+ *
+ * @hide
  */
 public final class StructFlock {
     /** The operation type, one of F_RDLCK, F_WRLCK, or F_UNLCK. */

diff --git a/luni/src/main/java/libcore/io/StructGroupReq.java b/luni/src/main/java/android/system/StructGroupReq.java
similarity index 96%
rename from luni/src/main/java/libcore/io/StructGroupReq.java
rename to luni/src/main/java/android/system/StructGroupReq.java
index 0bdf783..f7e7d0f 100644
--- a/luni/src/main/java/libcore/io/StructGroupReq.java
+++ b/luni/src/main/java/android/system/StructGroupReq.java

@@ -14,12 +14,14 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 import java.net.InetAddress;
 
 /**
  * Corresponds to C's {@code struct group_req}.
+ *
+ * @hide
  */
 public final class StructGroupReq {
     public final int gr_interface;

diff --git a/luni/src/main/java/libcore/io/StructGroupSourceReq.java b/luni/src/main/java/android/system/StructGroupSourceReq.java
similarity index 96%
rename from luni/src/main/java/libcore/io/StructGroupSourceReq.java
rename to luni/src/main/java/android/system/StructGroupSourceReq.java
index 3ac94b8..f3958ad 100644
--- a/luni/src/main/java/libcore/io/StructGroupSourceReq.java
+++ b/luni/src/main/java/android/system/StructGroupSourceReq.java

@@ -14,12 +14,14 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 import java.net.InetAddress;
 
 /**
  * Corresponds to C's {@code struct group_source_req}.
+ *
+ * @hide
  */
 public final class StructGroupSourceReq {
 

diff --git a/luni/src/main/java/libcore/io/StructLinger.java b/luni/src/main/java/android/system/StructLinger.java
similarity index 96%
rename from luni/src/main/java/libcore/io/StructLinger.java
rename to luni/src/main/java/android/system/StructLinger.java
index 9f149af..8c65336 100644
--- a/luni/src/main/java/libcore/io/StructLinger.java
+++ b/luni/src/main/java/android/system/StructLinger.java

@@ -14,11 +14,13 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 /**
  * Corresponds to C's {@code struct linger} from
  * <a href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_socket.h.html">&lt;sys/socket.h&gt;</a>
+ *
+ * @hide
  */
 public final class StructLinger {
     /** Whether or not linger is enabled. Non-zero is on. */

diff --git a/luni/src/main/java/libcore/io/StructPasswd.java b/luni/src/main/java/android/system/StructPasswd.java
similarity index 96%
rename from luni/src/main/java/libcore/io/StructPasswd.java
rename to luni/src/main/java/android/system/StructPasswd.java
index 6f5e058..9a94d3d 100644
--- a/luni/src/main/java/libcore/io/StructPasswd.java
+++ b/luni/src/main/java/android/system/StructPasswd.java

@@ -14,12 +14,14 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 /**
  * Information returned by getpwnam(3) and getpwuid(3). Corresponds to C's
  * {@code struct passwd} from
  * <a href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/pwd.h.html">&lt;pwd.h&gt;</a>
+ *
+ * @hide
  */
 public final class StructPasswd {
     public String pw_name;

diff --git a/luni/src/main/java/libcore/io/StructPollfd.java b/luni/src/main/java/android/system/StructPollfd.java
similarity index 97%
rename from luni/src/main/java/libcore/io/StructPollfd.java
rename to luni/src/main/java/android/system/StructPollfd.java
index c659d6e..9e65989 100644
--- a/luni/src/main/java/libcore/io/StructPollfd.java
+++ b/luni/src/main/java/android/system/StructPollfd.java

@@ -14,13 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 import java.io.FileDescriptor;
 
 /**
  * Corresponds to C's {@code struct pollfd} from
  * <a href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/poll.h.html">&lt;poll.h&gt;</a>
+ *
+ * @hide
  */
 public final class StructPollfd {
     /** The file descriptor to poll. */

diff --git a/luni/src/main/java/android/system/StructStat.java b/luni/src/main/java/android/system/StructStat.java
new file mode 100644
index 0000000..17221fd
--- /dev/null
+++ b/luni/src/main/java/android/system/StructStat.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.system;
+
+/**
+ * File information returned by fstat(2), lstat(2), and stat(2). Corresponds to C's
+ * {@code struct stat} from
+ * <a href="http://www.opengroup.org/onlinepubs/000095399/basedefs/sys/stat.h.html">&lt;stat.h&gt;</a>
+ *
+ * @hide
+ */
+public final class StructStat extends libcore.io.StructStat {
+  public StructStat(long st_dev, long st_ino, int st_mode, long st_nlink, int st_uid, int st_gid,
+                    long st_rdev, long st_size, long st_atime, long st_mtime, long st_ctime,
+                    long st_blksize, long st_blocks) {
+    super(st_dev, st_ino, st_mode, st_nlink, st_uid, st_gid,
+          st_rdev, st_size, st_atime, st_mtime, st_ctime,
+          st_blksize, st_blocks);
+  }
+}

diff --git a/luni/src/main/java/android/system/StructStatVfs.java b/luni/src/main/java/android/system/StructStatVfs.java
new file mode 100644
index 0000000..b0eedb7
--- /dev/null
+++ b/luni/src/main/java/android/system/StructStatVfs.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.system;
+
+/**
+ * File information returned by fstatvfs(2) and statvfs(2).
+ *
+ * @hide
+ */
+public final class StructStatVfs extends libcore.io.StructStatVfs {
+  public StructStatVfs(long f_bsize, long f_frsize, long f_blocks, long f_bfree, long f_bavail,
+                       long f_files, long f_ffree, long f_favail,
+                       long f_fsid, long f_flag, long f_namemax) {
+    super(f_bsize, f_frsize, f_blocks, f_bfree, f_bavail,
+          f_files, f_ffree, f_favail,
+          f_fsid, f_flag, f_namemax);
+  }
+}

diff --git a/luni/src/main/java/android/system/StructTimeval.java b/luni/src/main/java/android/system/StructTimeval.java
new file mode 100644
index 0000000..c31ab3a
--- /dev/null
+++ b/luni/src/main/java/android/system/StructTimeval.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.system;
+
+/**
+ * Corresponds to C's {@code struct timeval} from
+ * <a href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_time.h.html">&lt;sys/time.h&gt;</a>
+ *
+ * @hide
+ */
+public final class StructTimeval {
+  /** Seconds. */
+  public final long tv_sec;
+
+  /** Microseconds. */
+  public final long tv_usec;
+
+  private StructTimeval(long tv_sec, long tv_usec) {
+    this.tv_sec = tv_sec;
+    this.tv_usec = tv_usec;
+  }
+
+
+  public static StructTimeval fromMillis(long millis) {
+    long tv_sec = millis / 1000;
+    long tv_usec = (millis - (tv_sec * 1000)) * 1000;
+    return new StructTimeval(tv_sec, tv_usec);
+  }
+
+  public long toMillis() {
+    return (tv_sec * 1000) + (tv_usec / 1000);
+  }
+
+  @Override public String toString() {
+    return "StructTimeval[tv_sec=" + tv_sec + ",tv_usec=" + tv_usec + "]";
+  }
+}

diff --git a/luni/src/main/java/libcore/io/StructUcred.java b/luni/src/main/java/android/system/StructUcred.java
similarity index 96%
rename from luni/src/main/java/libcore/io/StructUcred.java
rename to luni/src/main/java/android/system/StructUcred.java
index c13212c..563a904 100644
--- a/luni/src/main/java/libcore/io/StructUcred.java
+++ b/luni/src/main/java/android/system/StructUcred.java

@@ -14,10 +14,12 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 /**
  * Corresponds to C's {@code struct ucred}.
+ *
+ * @hide
  */
 public final class StructUcred {
   /** The peer's process id. */

diff --git a/luni/src/main/java/libcore/io/StructUtsname.java b/luni/src/main/java/android/system/StructUtsname.java
similarity index 97%
rename from luni/src/main/java/libcore/io/StructUtsname.java
rename to luni/src/main/java/android/system/StructUtsname.java
index d7d606b..21e08bb 100644
--- a/luni/src/main/java/libcore/io/StructUtsname.java
+++ b/luni/src/main/java/android/system/StructUtsname.java

@@ -14,12 +14,14 @@
  * limitations under the License.
  */
 
-package libcore.io;
+package android.system;
 
 /**
  * Information returned by uname(2). Corresponds to C's
  * {@code struct utsname} from
  * <a href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_utsname.h.html">&lt;sys/utsname.h&gt;</a>
+ *
+ * @hide
  */
 public final class StructUtsname {
     /** The OS name, such as "Linux". */

diff --git a/luni/src/main/java/libcore/util/MutableBoolean.java b/luni/src/main/java/android/util/MutableBoolean.java
similarity index 83%
rename from luni/src/main/java/libcore/util/MutableBoolean.java
rename to luni/src/main/java/android/util/MutableBoolean.java
index 359a8f9..90bf68c 100644
--- a/luni/src/main/java/libcore/util/MutableBoolean.java
+++ b/luni/src/main/java/android/util/MutableBoolean.java

@@ -14,12 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.util;
 
+/**
+ * @hide
+ */
 public final class MutableBoolean {
-    public boolean value;
+  public boolean value;
 
-    public MutableBoolean(boolean value) {
-        this.value = value;
-    }
+  public MutableBoolean(boolean value) {
+    this.value = value;
+  }
 }

diff --git a/luni/src/main/java/libcore/util/MutableByte.java b/luni/src/main/java/android/util/MutableByte.java
similarity index 84%
rename from luni/src/main/java/libcore/util/MutableByte.java
rename to luni/src/main/java/android/util/MutableByte.java
index 13f780b..65738b9 100644
--- a/luni/src/main/java/libcore/util/MutableByte.java
+++ b/luni/src/main/java/android/util/MutableByte.java

@@ -14,12 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.util;
 
+/**
+ * @hide
+ */
 public final class MutableByte {
-    public byte value;
+  public byte value;
 
-    public MutableByte(byte value) {
-        this.value = value;
-    }
+  public MutableByte(byte value) {
+    this.value = value;
+  }
 }

diff --git a/luni/src/main/java/libcore/util/MutableChar.java b/luni/src/main/java/android/util/MutableChar.java
similarity index 84%
rename from luni/src/main/java/libcore/util/MutableChar.java
rename to luni/src/main/java/android/util/MutableChar.java
index 1cafc3c..b59bab3 100644
--- a/luni/src/main/java/libcore/util/MutableChar.java
+++ b/luni/src/main/java/android/util/MutableChar.java

@@ -14,12 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.util;
 
+/**
+ * @hide
+ */
 public final class MutableChar {
-    public char value;
+  public char value;
 
-    public MutableChar(char value) {
-        this.value = value;
-    }
+  public MutableChar(char value) {
+    this.value = value;
+  }
 }

diff --git a/luni/src/main/java/libcore/util/MutableDouble.java b/luni/src/main/java/android/util/MutableDouble.java
similarity index 83%
rename from luni/src/main/java/libcore/util/MutableDouble.java
rename to luni/src/main/java/android/util/MutableDouble.java
index 4473ae6..3e2cc3a 100644
--- a/luni/src/main/java/libcore/util/MutableDouble.java
+++ b/luni/src/main/java/android/util/MutableDouble.java

@@ -14,12 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.util;
 
+/**
+ * @hide
+ */
 public final class MutableDouble {
-    public double value;
+  public double value;
 
-    public MutableDouble(double value) {
-        this.value = value;
-    }
+  public MutableDouble(double value) {
+    this.value = value;
+  }
 }

diff --git a/luni/src/main/java/libcore/util/MutableFloat.java b/luni/src/main/java/android/util/MutableFloat.java
similarity index 83%
rename from luni/src/main/java/libcore/util/MutableFloat.java
rename to luni/src/main/java/android/util/MutableFloat.java
index f81fba5..6e30501 100644
--- a/luni/src/main/java/libcore/util/MutableFloat.java
+++ b/luni/src/main/java/android/util/MutableFloat.java

@@ -14,12 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.util;
 
+/**
+ * @hide
+ */
 public final class MutableFloat {
-    public float value;
+  public float value;
 
-    public MutableFloat(float value) {
-        this.value = value;
-    }
+  public MutableFloat(float value) {
+    this.value = value;
+  }
 }

diff --git a/luni/src/main/java/libcore/util/MutableInt.java b/luni/src/main/java/android/util/MutableInt.java
similarity index 84%
rename from luni/src/main/java/libcore/util/MutableInt.java
rename to luni/src/main/java/android/util/MutableInt.java
index c8feb3a..8220c44 100644
--- a/luni/src/main/java/libcore/util/MutableInt.java
+++ b/luni/src/main/java/android/util/MutableInt.java

@@ -14,12 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.util;
 
+/**
+ * @hide
+ */
 public final class MutableInt {
-    public int value;
+  public int value;
 
-    public MutableInt(int value) {
-        this.value = value;
-    }
+  public MutableInt(int value) {
+    this.value = value;
+  }
 }

diff --git a/luni/src/main/java/libcore/util/MutableLong.java b/luni/src/main/java/android/util/MutableLong.java
similarity index 84%
rename from luni/src/main/java/libcore/util/MutableLong.java
rename to luni/src/main/java/android/util/MutableLong.java
index ad9b78e..5df6a0d 100644
--- a/luni/src/main/java/libcore/util/MutableLong.java
+++ b/luni/src/main/java/android/util/MutableLong.java

@@ -14,12 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.util;
 
+/**
+ * @hide
+ */
 public final class MutableLong {
-    public long value;
+  public long value;
 
-    public MutableLong(long value) {
-        this.value = value;
-    }
+  public MutableLong(long value) {
+    this.value = value;
+  }
 }

diff --git a/luni/src/main/java/libcore/util/MutableShort.java b/luni/src/main/java/android/util/MutableShort.java
similarity index 83%
rename from luni/src/main/java/libcore/util/MutableShort.java
rename to luni/src/main/java/android/util/MutableShort.java
index 78b4c33..3880fef 100644
--- a/luni/src/main/java/libcore/util/MutableShort.java
+++ b/luni/src/main/java/android/util/MutableShort.java

@@ -14,12 +14,15 @@
  * limitations under the License.
  */
 
-package libcore.util;
+package android.util;
 
+/**
+ * @hide
+ */
 public final class MutableShort {
-    public short value;
+  public short value;
 
-    public MutableShort(short value) {
-        this.value = value;
-    }
+  public MutableShort(short value) {
+    this.value = value;
+  }
 }

diff --git a/luni/src/main/java/java/io/File.java b/luni/src/main/java/java/io/File.java
index 9b98ecb..d107c28 100644
--- a/luni/src/main/java/java/io/File.java
+++ b/luni/src/main/java/java/io/File.java

@@ -17,6 +17,9 @@
 
 package java.io;
 
+import android.system.ErrnoException;
+import android.system.StructStat;
+import android.system.StructStatVfs;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
@@ -24,12 +27,9 @@
 import java.util.List;
 import java.util.Random;
 import libcore.io.DeleteOnExit;
-import libcore.io.ErrnoException;
 import libcore.io.IoUtils;
 import libcore.io.Libcore;
-import libcore.io.StructStat;
-import libcore.io.StructStatVfs;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * An "abstract" representation of a file system entity identified by a

diff --git a/luni/src/main/java/java/io/FileDescriptor.java b/luni/src/main/java/java/io/FileDescriptor.java
index e4eb06cc..cb38123 100644
--- a/luni/src/main/java/java/io/FileDescriptor.java
+++ b/luni/src/main/java/java/io/FileDescriptor.java

@@ -17,9 +17,9 @@
 
 package java.io;
 
-import libcore.io.ErrnoException;
+import android.system.ErrnoException;
 import libcore.io.Libcore;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * Wraps a Unix file descriptor. It's possible to get the file descriptor used by some

diff --git a/luni/src/main/java/java/io/FileInputStream.java b/luni/src/main/java/java/io/FileInputStream.java
index 5debe64..7944ef1 100644
--- a/luni/src/main/java/java/io/FileInputStream.java
+++ b/luni/src/main/java/java/io/FileInputStream.java

@@ -19,13 +19,13 @@
 
 import dalvik.system.CloseGuard;
 
-import java.nio.NioUtils;
+import android.system.ErrnoException;
 import java.nio.channels.FileChannel;
-import libcore.io.ErrnoException;
+import java.nio.NioUtils;
 import libcore.io.IoBridge;
 import libcore.io.Libcore;
 import libcore.io.Streams;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * An input stream that reads bytes from a file.

diff --git a/luni/src/main/java/java/io/FileOutputStream.java b/luni/src/main/java/java/io/FileOutputStream.java
index e796e80..f91ee20 100644
--- a/luni/src/main/java/java/io/FileOutputStream.java
+++ b/luni/src/main/java/java/io/FileOutputStream.java

@@ -22,7 +22,7 @@
 import java.nio.channels.FileChannel;
 import libcore.io.IoBridge;
 
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * An output stream that writes bytes to a file. If the output file exists, it

diff --git a/luni/src/main/java/java/io/RandomAccessFile.java b/luni/src/main/java/java/io/RandomAccessFile.java
index eac7641..da99765 100644
--- a/luni/src/main/java/java/io/RandomAccessFile.java
+++ b/luni/src/main/java/java/io/RandomAccessFile.java

@@ -17,18 +17,18 @@
 
 package java.io;
 
+import android.system.ErrnoException;
 import dalvik.system.CloseGuard;
 import java.nio.ByteOrder;
-import java.nio.NioUtils;
 import java.nio.channels.FileChannel;
 import java.nio.charset.ModifiedUtf8;
+import java.nio.NioUtils;
 import java.util.Arrays;
-import libcore.io.ErrnoException;
 import libcore.io.IoBridge;
 import libcore.io.Libcore;
 import libcore.io.Memory;
 import libcore.io.SizeOf;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * Allows reading from and writing to a file in a random-access manner. This is

diff --git a/luni/src/main/java/java/lang/ProcessManager.java b/luni/src/main/java/java/lang/ProcessManager.java
index 28314b7..ec87fda 100644
--- a/luni/src/main/java/java/lang/ProcessManager.java
+++ b/luni/src/main/java/java/lang/ProcessManager.java

@@ -16,23 +16,23 @@
 
 package java.lang;
 
+import android.system.ErrnoException;
+import android.util.MutableInt;
 import java.io.File;
 import java.io.FileDescriptor;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
-import java.io.IOException;
 import java.io.InputStream;
+import java.io.IOException;
 import java.io.OutputStream;
 import java.lang.ref.ReferenceQueue;
 import java.lang.ref.WeakReference;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
-import libcore.io.ErrnoException;
 import libcore.io.IoUtils;
 import libcore.io.Libcore;
-import libcore.util.MutableInt;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * Manages child processes.

diff --git a/luni/src/main/java/java/lang/Runtime.java b/luni/src/main/java/java/lang/Runtime.java
index 8538f8a..4b66c2d 100644
--- a/luni/src/main/java/java/lang/Runtime.java
+++ b/luni/src/main/java/java/lang/Runtime.java

@@ -48,7 +48,7 @@
 import libcore.io.IoUtils;
 import libcore.io.Libcore;
 import libcore.util.EmptyArray;
-import static libcore.io.OsConstants._SC_NPROCESSORS_CONF;
+import static android.system.OsConstants._SC_NPROCESSORS_CONF;
 
 /**
  * Allows Java applications to interface with the environment in which they are

diff --git a/luni/src/main/java/java/lang/System.java b/luni/src/main/java/java/lang/System.java
index 3f72c95..2d33bc6 100644
--- a/luni/src/main/java/java/lang/System.java
+++ b/luni/src/main/java/java/lang/System.java

@@ -32,6 +32,9 @@
 
 package java.lang;
 
+import android.system.ErrnoException;
+import android.system.StructPasswd;
+import android.system.StructUtsname;
 import dalvik.system.VMRuntime;
 import dalvik.system.VMStack;
 import java.io.BufferedInputStream;
@@ -39,8 +42,8 @@
 import java.io.FileDescriptor;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
-import java.io.IOException;
 import java.io.InputStream;
+import java.io.IOException;
 import java.io.PrintStream;
 import java.nio.channels.Channel;
 import java.nio.channels.spi.SelectorProvider;
@@ -51,10 +54,7 @@
 import java.util.Properties;
 import java.util.Set;
 import libcore.icu.ICU;
-import libcore.io.ErrnoException;
 import libcore.io.Libcore;
-import libcore.io.StructPasswd;
-import libcore.io.StructUtsname;
 
 /**
  * Provides access to system-related information and resources including

diff --git a/luni/src/main/java/java/net/DatagramSocket.java b/luni/src/main/java/java/net/DatagramSocket.java
index 26825d2..f9b72d8 100644
--- a/luni/src/main/java/java/net/DatagramSocket.java
+++ b/luni/src/main/java/java/net/DatagramSocket.java

@@ -17,14 +17,14 @@
 
 package java.net;
 
+import android.system.ErrnoException;
 import java.io.Closeable;
 import java.io.FileDescriptor;
 import java.io.IOException;
 import java.nio.channels.DatagramChannel;
-import libcore.io.ErrnoException;
 import libcore.io.IoBridge;
 import libcore.io.Libcore;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * This class implements a UDP socket for sending and receiving {@code

diff --git a/luni/src/main/java/java/net/Inet4Address.java b/luni/src/main/java/java/net/Inet4Address.java
index 7c26639..f0b1b5b 100644
--- a/luni/src/main/java/java/net/Inet4Address.java
+++ b/luni/src/main/java/java/net/Inet4Address.java

@@ -20,7 +20,7 @@
 import java.io.ObjectStreamException;
 import java.nio.ByteOrder;
 import libcore.io.Memory;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * An IPv4 address. See {@link InetAddress}.

diff --git a/luni/src/main/java/java/net/Inet6Address.java b/luni/src/main/java/java/net/Inet6Address.java
index 37e9c18..8ab0f8d 100644
--- a/luni/src/main/java/java/net/Inet6Address.java
+++ b/luni/src/main/java/java/net/Inet6Address.java

@@ -23,7 +23,7 @@
 import java.io.ObjectStreamField;
 import java.util.Arrays;
 import java.util.Enumeration;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * An IPv6 address. See {@link InetAddress}.

diff --git a/luni/src/main/java/java/net/InetAddress.java b/luni/src/main/java/java/net/InetAddress.java
index 885b472..e31b4c3 100644
--- a/luni/src/main/java/java/net/InetAddress.java
+++ b/luni/src/main/java/java/net/InetAddress.java

@@ -17,6 +17,9 @@
 
 package java.net;
 
+import android.system.ErrnoException;
+import android.system.GaiException;
+import android.system.StructAddrinfo;
 import dalvik.system.BlockGuard;
 import java.io.FileDescriptor;
 import java.io.IOException;
@@ -28,16 +31,13 @@
 import java.nio.ByteOrder;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.List;
-import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicBoolean;
-import libcore.io.ErrnoException;
-import libcore.io.GaiException;
+import java.util.concurrent.CountDownLatch;
+import java.util.List;
 import libcore.io.IoBridge;
 import libcore.io.Libcore;
 import libcore.io.Memory;
-import libcore.io.StructAddrinfo;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * An Internet Protocol (IP) address. This can be either an IPv4 address or an IPv6 address, and

diff --git a/luni/src/main/java/java/net/InetUnixAddress.java b/luni/src/main/java/java/net/InetUnixAddress.java
index 44b9cba..51236e2 100644
--- a/luni/src/main/java/java/net/InetUnixAddress.java
+++ b/luni/src/main/java/java/net/InetUnixAddress.java

@@ -18,7 +18,7 @@
 
 import java.nio.charset.StandardCharsets;
 
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * An AF_UNIX address. See {@link InetAddress}.

diff --git a/luni/src/main/java/java/net/NetworkInterface.java b/luni/src/main/java/java/net/NetworkInterface.java
index 3128b98..852c09b 100644
--- a/luni/src/main/java/java/net/NetworkInterface.java
+++ b/luni/src/main/java/java/net/NetworkInterface.java

@@ -17,6 +17,7 @@
 
 package java.net;
 
+import android.system.ErrnoException;
 import java.io.File;
 import java.io.FileDescriptor;
 import java.io.IOException;
@@ -26,10 +27,9 @@
 import java.util.Enumeration;
 import java.util.LinkedList;
 import java.util.List;
-import libcore.io.ErrnoException;
 import libcore.io.IoUtils;
 import libcore.io.Libcore;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * This class is used to represent a network interface of the local device. An

diff --git a/luni/src/main/java/java/net/PlainDatagramSocketImpl.java b/luni/src/main/java/java/net/PlainDatagramSocketImpl.java
index a9ade28..eb0c99d 100644
--- a/luni/src/main/java/java/net/PlainDatagramSocketImpl.java
+++ b/luni/src/main/java/java/net/PlainDatagramSocketImpl.java

@@ -17,15 +17,15 @@
 
 package java.net;
 
+import android.system.ErrnoException;
+import android.system.StructGroupReq;
 import dalvik.system.CloseGuard;
 import java.io.FileDescriptor;
 import java.io.IOException;
-import libcore.io.ErrnoException;
 import libcore.io.IoBridge;
 import libcore.io.Libcore;
-import libcore.io.StructGroupReq;
 import libcore.util.EmptyArray;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * @hide used in java.nio.

diff --git a/luni/src/main/java/java/net/PlainSocketImpl.java b/luni/src/main/java/java/net/PlainSocketImpl.java
index e3988ed..4e5ba44 100644
--- a/luni/src/main/java/java/net/PlainSocketImpl.java
+++ b/luni/src/main/java/java/net/PlainSocketImpl.java

@@ -17,19 +17,19 @@
 
 package java.net;
 
+import android.system.ErrnoException;
 import dalvik.system.CloseGuard;
 import java.io.FileDescriptor;
-import java.io.IOException;
 import java.io.InputStream;
+import java.io.IOException;
 import java.io.OutputStream;
 import java.nio.ByteOrder;
 import java.util.Arrays;
-import libcore.io.ErrnoException;
 import libcore.io.IoBridge;
 import libcore.io.Libcore;
 import libcore.io.Memory;
 import libcore.io.Streams;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * @hide used in java.nio.

diff --git a/luni/src/main/java/java/nio/DatagramChannelImpl.java b/luni/src/main/java/java/nio/DatagramChannelImpl.java
index 2f04b30..8a5dbb6 100644
--- a/luni/src/main/java/java/nio/DatagramChannelImpl.java
+++ b/luni/src/main/java/java/nio/DatagramChannelImpl.java

@@ -17,9 +17,10 @@
 
 package java.nio;
 
+import android.system.ErrnoException;
 import java.io.FileDescriptor;
-import java.io.IOException;
 import java.io.InterruptedIOException;
+import java.io.IOException;
 import java.net.ConnectException;
 import java.net.DatagramPacket;
 import java.net.DatagramSocket;
@@ -40,13 +41,11 @@
 import java.nio.channels.IllegalBlockingModeException;
 import java.nio.channels.MembershipKey;
 import java.nio.channels.NotYetConnectedException;
+import java.nio.channels.spi.SelectorProvider;
 import java.nio.channels.UnresolvedAddressException;
 import java.nio.channels.UnsupportedAddressTypeException;
-import java.nio.channels.spi.SelectorProvider;
 import java.util.Arrays;
 import java.util.Set;
-
-import libcore.io.ErrnoException;
 import libcore.io.IoBridge;
 import libcore.io.IoUtils;
 import libcore.io.Libcore;

diff --git a/luni/src/main/java/java/nio/FileChannelImpl.java b/luni/src/main/java/java/nio/FileChannelImpl.java
index 9a47706..4ed7dba 100644
--- a/luni/src/main/java/java/nio/FileChannelImpl.java
+++ b/luni/src/main/java/java/nio/FileChannelImpl.java

@@ -17,6 +17,9 @@
 
 package java.nio;
 
+import android.system.ErrnoException;
+import android.system.StructFlock;
+import android.util.MutableLong;
 import java.io.Closeable;
 import java.io.FileDescriptor;
 import java.io.IOException;
@@ -32,11 +35,8 @@
 import java.util.Comparator;
 import java.util.SortedSet;
 import java.util.TreeSet;
-import libcore.io.ErrnoException;
 import libcore.io.Libcore;
-import libcore.io.StructFlock;
-import libcore.util.MutableLong;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * Our concrete implementation of the abstract FileChannel class.

diff --git a/luni/src/main/java/java/nio/IoVec.java b/luni/src/main/java/java/nio/IoVec.java
index f14f4f2..e20709c 100644
--- a/luni/src/main/java/java/nio/IoVec.java
+++ b/luni/src/main/java/java/nio/IoVec.java

@@ -16,10 +16,10 @@
 
 package java.nio;
 
+import android.system.ErrnoException;
 import java.io.FileDescriptor;
 import java.io.IOException;
 import libcore.io.Libcore;
-import libcore.io.ErrnoException;
 
 /**
  * Used to implement java.nio read(ByteBuffer[])/write(ByteBuffer[]) operations as POSIX readv(2)

diff --git a/luni/src/main/java/java/nio/MappedByteBuffer.java b/luni/src/main/java/java/nio/MappedByteBuffer.java
index 5782457..ce19c0c 100644
--- a/luni/src/main/java/java/nio/MappedByteBuffer.java
+++ b/luni/src/main/java/java/nio/MappedByteBuffer.java

@@ -16,11 +16,11 @@
 
 package java.nio;
 
+import android.system.ErrnoException;
 import java.nio.channels.FileChannel.MapMode;
-import libcore.io.ErrnoException;
 import libcore.io.Libcore;
-import static libcore.io.OsConstants.MS_SYNC;
-import static libcore.io.OsConstants._SC_PAGE_SIZE;
+import static android.system.OsConstants.MS_SYNC;
+import static android.system.OsConstants._SC_PAGE_SIZE;
 
 /**
  * {@code MappedByteBuffer} is a special kind of direct byte buffer which maps a

diff --git a/luni/src/main/java/java/nio/MemoryBlock.java b/luni/src/main/java/java/nio/MemoryBlock.java
index 6052b8f..1ce8fea 100644
--- a/luni/src/main/java/java/nio/MemoryBlock.java
+++ b/luni/src/main/java/java/nio/MemoryBlock.java

@@ -17,18 +17,18 @@
 
 package java.nio;
 
+import android.system.ErrnoException;
 import dalvik.system.VMRuntime;
 import java.io.FileDescriptor;
 import java.io.IOException;
 import java.nio.channels.FileChannel.MapMode;
-import libcore.io.ErrnoException;
 import libcore.io.Libcore;
 import libcore.io.Memory;
 
-import static libcore.io.OsConstants.MAP_PRIVATE;
-import static libcore.io.OsConstants.MAP_SHARED;
-import static libcore.io.OsConstants.PROT_READ;
-import static libcore.io.OsConstants.PROT_WRITE;
+import static android.system.OsConstants.MAP_PRIVATE;
+import static android.system.OsConstants.MAP_SHARED;
+import static android.system.OsConstants.PROT_READ;
+import static android.system.OsConstants.PROT_WRITE;
 
 class MemoryBlock {
     /**

diff --git a/luni/src/main/java/java/nio/MulticastMembershipHandler.java b/luni/src/main/java/java/nio/MulticastMembershipHandler.java
index 7564d4e..2fe8130 100644
--- a/luni/src/main/java/java/nio/MulticastMembershipHandler.java
+++ b/luni/src/main/java/java/nio/MulticastMembershipHandler.java

@@ -1,5 +1,7 @@
 package java.nio;
 
+import android.system.StructGroupReq;
+import android.system.StructGroupSourceReq;
 import java.net.InetAddress;
 import java.net.NetworkInterface;
 import java.net.SocketException;
@@ -8,10 +10,7 @@
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
-
 import libcore.io.IoBridge;
-import libcore.io.StructGroupReq;
-import libcore.io.StructGroupSourceReq;
 
 /**
  * A helper class for {@link DatagramChannelImpl} that keeps track of multicast group

diff --git a/luni/src/main/java/java/nio/PipeImpl.java b/luni/src/main/java/java/nio/PipeImpl.java
index d4dde3b..ebc8a91 100644
--- a/luni/src/main/java/java/nio/PipeImpl.java
+++ b/luni/src/main/java/java/nio/PipeImpl.java

@@ -16,16 +16,16 @@
 
 package java.nio;
 
+import android.system.ErrnoException;
 import java.io.Closeable;
 import java.io.FileDescriptor;
 import java.io.IOException;
 import java.nio.channels.Pipe;
 import java.nio.channels.SocketChannel;
 import java.nio.channels.spi.SelectorProvider;
-import libcore.io.ErrnoException;
 import libcore.io.IoUtils;
 import libcore.io.Libcore;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /*
  * Implements {@link java.nio.channels.Pipe}.

diff --git a/luni/src/main/java/java/nio/SelectorImpl.java b/luni/src/main/java/java/nio/SelectorImpl.java
index 3495523..efa8712 100644
--- a/luni/src/main/java/java/nio/SelectorImpl.java
+++ b/luni/src/main/java/java/nio/SelectorImpl.java

@@ -15,9 +15,11 @@
  */
 package java.nio;
 
+import android.system.ErrnoException;
+import android.system.StructPollfd;
 import java.io.FileDescriptor;
-import java.io.IOException;
 import java.io.InterruptedIOException;
+import java.io.IOException;
 import java.nio.channels.ClosedSelectorException;
 import java.nio.channels.IllegalSelectorException;
 import java.nio.channels.SelectionKey;
@@ -32,20 +34,18 @@
 import java.util.Iterator;
 import java.util.Set;
 import java.util.UnsafeArrayList;
-import libcore.io.ErrnoException;
 import libcore.io.IoBridge;
 import libcore.io.IoUtils;
 import libcore.io.Libcore;
-import libcore.io.StructPollfd;
 
+import static android.system.OsConstants.EINTR;
+import static android.system.OsConstants.POLLHUP;
+import static android.system.OsConstants.POLLIN;
+import static android.system.OsConstants.POLLOUT;
 import static java.nio.channels.SelectionKey.OP_ACCEPT;
 import static java.nio.channels.SelectionKey.OP_CONNECT;
 import static java.nio.channels.SelectionKey.OP_READ;
 import static java.nio.channels.SelectionKey.OP_WRITE;
-import static libcore.io.OsConstants.EINTR;
-import static libcore.io.OsConstants.POLLHUP;
-import static libcore.io.OsConstants.POLLIN;
-import static libcore.io.OsConstants.POLLOUT;
 
 /*
  * Default implementation of java.nio.channels.Selector

diff --git a/luni/src/main/java/java/nio/ServerSocketChannelImpl.java b/luni/src/main/java/java/nio/ServerSocketChannelImpl.java
index 5adea1a..d2cbf36 100644
--- a/luni/src/main/java/java/nio/ServerSocketChannelImpl.java
+++ b/luni/src/main/java/java/nio/ServerSocketChannelImpl.java

@@ -17,6 +17,7 @@
 
 package java.nio;
 
+import android.system.ErrnoException;
 import java.io.FileDescriptor;
 import java.io.IOException;
 import java.net.InetSocketAddress;
@@ -32,14 +33,12 @@
 import java.nio.channels.NotYetBoundException;
 import java.nio.channels.ServerSocketChannel;
 import java.nio.channels.SocketChannel;
+import java.nio.channels.spi.SelectorProvider;
 import java.nio.channels.UnresolvedAddressException;
 import java.nio.channels.UnsupportedAddressTypeException;
-import java.nio.channels.spi.SelectorProvider;
 import java.util.Set;
-
-import libcore.io.ErrnoException;
 import libcore.io.IoUtils;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * The default ServerSocketChannel.

diff --git a/luni/src/main/java/java/nio/SocketChannelImpl.java b/luni/src/main/java/java/nio/SocketChannelImpl.java
index 2ed11fc..7c3cd78 100644
--- a/luni/src/main/java/java/nio/SocketChannelImpl.java
+++ b/luni/src/main/java/java/nio/SocketChannelImpl.java

@@ -17,11 +17,12 @@
 
 package java.nio;
 
+import android.system.ErrnoException;
 import java.io.FileDescriptor;
 import java.io.FilterInputStream;
 import java.io.FilterOutputStream;
-import java.io.IOException;
 import java.io.InputStream;
+import java.io.IOException;
 import java.io.OutputStream;
 import java.net.ConnectException;
 import java.net.Inet4Address;
@@ -42,17 +43,15 @@
 import java.nio.channels.NoConnectionPendingException;
 import java.nio.channels.NotYetConnectedException;
 import java.nio.channels.SocketChannel;
+import java.nio.channels.spi.SelectorProvider;
 import java.nio.channels.UnresolvedAddressException;
 import java.nio.channels.UnsupportedAddressTypeException;
-import java.nio.channels.spi.SelectorProvider;
 import java.util.Arrays;
 import java.util.Set;
-
-import libcore.io.ErrnoException;
-import libcore.io.Libcore;
 import libcore.io.IoBridge;
 import libcore.io.IoUtils;
-import static libcore.io.OsConstants.*;
+import libcore.io.Libcore;
+import static android.system.OsConstants.*;
 
 /*
  * The default implementation class of java.nio.channels.SocketChannel.

diff --git a/luni/src/main/java/libcore/io/BlockGuardOs.java b/luni/src/main/java/libcore/io/BlockGuardOs.java
index eaa7f0c..238c5bd 100644
--- a/luni/src/main/java/libcore/io/BlockGuardOs.java
+++ b/luni/src/main/java/libcore/io/BlockGuardOs.java

@@ -16,6 +16,12 @@
 
 package libcore.io;
 
+import android.system.ErrnoException;
+import android.system.StructLinger;
+import android.system.StructPollfd;
+import android.system.StructStat;
+import android.system.StructStatVfs;
+import android.util.MutableLong;
 import dalvik.system.BlockGuard;
 import dalvik.system.SocketTagger;
 import java.io.FileDescriptor;
@@ -24,8 +30,7 @@
 import java.net.InetSocketAddress;
 import java.net.SocketException;
 import java.nio.ByteBuffer;
-import libcore.util.MutableLong;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * Informs BlockGuard of any activity it should be aware of.

diff --git a/luni/src/main/java/libcore/io/ErrnoException.java b/luni/src/main/java/libcore/io/ErrnoException.java
index f484ce9..2a8c1c2 100644
--- a/luni/src/main/java/libcore/io/ErrnoException.java
+++ b/luni/src/main/java/libcore/io/ErrnoException.java

@@ -20,11 +20,11 @@
 import java.net.SocketException;
 
 /**
- * A checked exception thrown when {@link Os} methods fail. This exception contains the native
+ * An unchecked exception thrown when {@link Os} methods fail. This exception contains the native
  * errno value, for comparison against the constants in {@link OsConstants}, should sophisticated
  * callers need to adjust their behavior based on the exact failure.
  */
-public final class ErrnoException extends Exception {
+public /* not final for android.system.ErrnoException */ class ErrnoException extends Exception {
     private final String functionName;
     public final int errno;
 

diff --git a/luni/src/main/java/libcore/io/ForwardingOs.java b/luni/src/main/java/libcore/io/ForwardingOs.java
index 0b49071..3e63cf6 100644
--- a/luni/src/main/java/libcore/io/ForwardingOs.java
+++ b/luni/src/main/java/libcore/io/ForwardingOs.java

@@ -16,6 +16,22 @@
 
 package libcore.io;
 
+import android.system.ErrnoException;
+import android.system.GaiException;
+import android.system.StructAddrinfo;
+import android.system.StructFlock;
+import android.system.StructGroupReq;
+import android.system.StructGroupSourceReq;
+import android.system.StructLinger;
+import android.system.StructPasswd;
+import android.system.StructPollfd;
+import android.system.StructStat;
+import android.system.StructStatVfs;
+import android.system.StructTimeval;
+import android.system.StructUcred;
+import android.system.StructUtsname;
+import android.util.MutableInt;
+import android.util.MutableLong;
 import java.io.FileDescriptor;
 import java.io.InterruptedIOException;
 import java.net.InetAddress;
@@ -23,8 +39,6 @@
 import java.net.SocketAddress;
 import java.net.SocketException;
 import java.nio.ByteBuffer;
-import libcore.util.MutableInt;
-import libcore.util.MutableLong;
 
 /**
  * Subclass this if you want to override some {@link Os} methods but otherwise delegate.

diff --git a/luni/src/main/java/libcore/io/GaiException.java b/luni/src/main/java/libcore/io/GaiException.java
deleted file mode 100644
index 08143dc..0000000
--- a/luni/src/main/java/libcore/io/GaiException.java
+++ /dev/null

@@ -1,66 +0,0 @@
-/*
- * Copyright (C) 2011 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package libcore.io;
-
-import java.net.UnknownHostException;
-import libcore.io.OsConstants;
-
-/**
- * An unchecked exception thrown when the {@link Os} {@code getaddrinfo} or {@code getnameinfo}
- * methods fail. This exception contains the native error value, for comparison against the
- * {@code GAI_} constants in {@link OsConstants}, should sophisticated
- * callers need to adjust their behavior based on the exact failure.
- */
-public final class GaiException extends RuntimeException {
-    private final String functionName;
-    public final int error;
-
-    public GaiException(String functionName, int error) {
-        this.functionName = functionName;
-        this.error = error;
-    }
-
-    public GaiException(String functionName, int error, Throwable cause) {
-        super(cause);
-        this.functionName = functionName;
-        this.error = error;
-    }
-
-    /**
-     * Converts the stashed function name and error value to a human-readable string.
-     * We do this here rather than in the constructor so that callers only pay for
-     * this if they need it.
-     */
-    @Override public String getMessage() {
-        String gaiName = OsConstants.gaiName(error);
-        if (gaiName == null) {
-            gaiName = "GAI_ error " + error;
-        }
-        String description = Libcore.os.gai_strerror(error);
-        return functionName + " failed: " + gaiName + " (" + description + ")";
-    }
-
-    public UnknownHostException rethrowAsUnknownHostException(String detailMessage) throws UnknownHostException {
-        UnknownHostException newException = new UnknownHostException(detailMessage);
-        newException.initCause(this);
-        throw newException;
-    }
-
-    public UnknownHostException rethrowAsUnknownHostException() throws UnknownHostException {
-        throw rethrowAsUnknownHostException(getMessage());
-    }
-}

diff --git a/luni/src/main/java/libcore/io/IoBridge.java b/luni/src/main/java/libcore/io/IoBridge.java
index 89070cd..1e2ed7d 100644
--- a/luni/src/main/java/libcore/io/IoBridge.java
+++ b/luni/src/main/java/libcore/io/IoBridge.java

@@ -16,6 +16,12 @@
 
 package libcore.io;
 
+import android.system.StructGroupReq;
+import android.system.StructGroupSourceReq;
+import android.system.StructLinger;
+import android.system.StructPollfd;
+import android.system.StructTimeval;
+import android.util.MutableInt;
 import java.io.FileDescriptor;
 import java.io.FileNotFoundException;
 import java.io.IOException;
@@ -35,8 +41,7 @@
 import java.net.UnknownHostException;
 import java.nio.ByteBuffer;
 import java.util.Arrays;
-import static libcore.io.OsConstants.*;
-import libcore.util.MutableInt;
+import static android.system.OsConstants.*;
 
 /**
  * Implements java.io/java.net/java.nio semantics in terms of the underlying POSIX system calls.

diff --git a/luni/src/main/java/libcore/io/IoUtils.java b/luni/src/main/java/libcore/io/IoUtils.java
index 10ef671..27da93f 100644
--- a/luni/src/main/java/libcore/io/IoUtils.java
+++ b/luni/src/main/java/libcore/io/IoUtils.java

@@ -25,7 +25,7 @@
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
 import java.util.Random;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 public final class IoUtils {
     private static final Random TEMPORARY_DIRECTORY_PRNG = new Random();

diff --git a/luni/src/main/java/libcore/io/MemoryMappedFile.java b/luni/src/main/java/libcore/io/MemoryMappedFile.java
index 2d8aa2b..b4cd8fc 100644
--- a/luni/src/main/java/libcore/io/MemoryMappedFile.java
+++ b/luni/src/main/java/libcore/io/MemoryMappedFile.java

@@ -16,16 +16,16 @@
 
 package libcore.io;
 
+import android.system.ErrnoException;
 import java.io.FileDescriptor;
 import java.io.IOException;
 import java.io.RandomAccessFile;
 import java.nio.ByteOrder;
-import java.nio.NioUtils;
 import java.nio.channels.FileChannel;
-import libcore.io.ErrnoException;
+import java.nio.NioUtils;
 import libcore.io.Libcore;
 import libcore.io.Memory;
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 /**
  * A memory-mapped file. Use {@link #mmap} to map a file, {@link #close} to unmap a file,

diff --git a/luni/src/main/java/libcore/io/Os.java b/luni/src/main/java/libcore/io/Os.java
index 2065c70..7a71261 100644
--- a/luni/src/main/java/libcore/io/Os.java
+++ b/luni/src/main/java/libcore/io/Os.java

@@ -16,6 +16,22 @@
 
 package libcore.io;
 
+import android.system.ErrnoException;
+import android.system.GaiException;
+import android.system.StructAddrinfo;
+import android.system.StructFlock;
+import android.system.StructGroupReq;
+import android.system.StructGroupSourceReq;
+import android.system.StructLinger;
+import android.system.StructPasswd;
+import android.system.StructPollfd;
+import android.system.StructStat;
+import android.system.StructStatVfs;
+import android.system.StructTimeval;
+import android.system.StructUcred;
+import android.system.StructUtsname;
+import android.util.MutableInt;
+import android.util.MutableLong;
 import java.io.FileDescriptor;
 import java.io.InterruptedIOException;
 import java.net.InetAddress;
@@ -23,8 +39,6 @@
 import java.net.SocketAddress;
 import java.net.SocketException;
 import java.nio.ByteBuffer;
-import libcore.util.MutableInt;
-import libcore.util.MutableLong;
 
 public interface Os {
     public FileDescriptor accept(FileDescriptor fd, InetSocketAddress peerAddress) throws ErrnoException, SocketException;

diff --git a/luni/src/main/java/libcore/io/OsConstants.java b/luni/src/main/java/libcore/io/OsConstants.java
index 49b0182..2c97122 100644
--- a/luni/src/main/java/libcore/io/OsConstants.java
+++ b/luni/src/main/java/libcore/io/OsConstants.java

@@ -16,8 +16,9 @@
 
 package libcore.io;
 
-public final class OsConstants {
-    private OsConstants() { }
+public /* Not final because of android.system.OsConstants */ class OsConstants {
+    // So android.system.OsConstants can subclass us.
+    protected OsConstants() { }
 
     public static boolean S_ISBLK(int mode) { return (mode & S_IFMT) == S_IFBLK; }
     public static boolean S_ISCHR(int mode) { return (mode & S_IFMT) == S_IFCHR; }

diff --git a/luni/src/main/java/libcore/io/Posix.java b/luni/src/main/java/libcore/io/Posix.java
index a5c3eb0..c2dccce 100644
--- a/luni/src/main/java/libcore/io/Posix.java
+++ b/luni/src/main/java/libcore/io/Posix.java

@@ -16,6 +16,22 @@
 
 package libcore.io;
 
+import android.system.ErrnoException;
+import android.system.GaiException;
+import android.system.StructAddrinfo;
+import android.system.StructFlock;
+import android.system.StructGroupReq;
+import android.system.StructGroupSourceReq;
+import android.system.StructLinger;
+import android.system.StructPasswd;
+import android.system.StructPollfd;
+import android.system.StructStat;
+import android.system.StructStatVfs;
+import android.system.StructTimeval;
+import android.system.StructUcred;
+import android.system.StructUtsname;
+import android.util.MutableInt;
+import android.util.MutableLong;
 import java.io.FileDescriptor;
 import java.io.InterruptedIOException;
 import java.net.InetAddress;
@@ -24,8 +40,6 @@
 import java.net.SocketException;
 import java.nio.ByteBuffer;
 import java.nio.NioUtils;
-import libcore.util.MutableInt;
-import libcore.util.MutableLong;
 
 public final class Posix implements Os {
     Posix() { }

diff --git a/luni/src/main/java/libcore/io/StructStat.java b/luni/src/main/java/libcore/io/StructStat.java
index 00371fb..29685c6 100644
--- a/luni/src/main/java/libcore/io/StructStat.java
+++ b/luni/src/main/java/libcore/io/StructStat.java

@@ -21,7 +21,7 @@
  * {@code struct stat} from
  * <a href="http://www.opengroup.org/onlinepubs/000095399/basedefs/sys/stat.h.html">&lt;stat.h&gt;</a>
  */
-public final class StructStat {
+public /* not final for android.system.StructStat */ class StructStat {
     /** Device ID of device containing file. */
     public final long st_dev; /*dev_t*/
 

diff --git a/luni/src/main/java/libcore/io/StructStatVfs.java b/luni/src/main/java/libcore/io/StructStatVfs.java
index bdff111..4beb69f 100644
--- a/luni/src/main/java/libcore/io/StructStatVfs.java
+++ b/luni/src/main/java/libcore/io/StructStatVfs.java

@@ -19,7 +19,7 @@
 /**
  * File information returned by fstatvfs(2) and statvfs(2).
  */
-public final class StructStatVfs {
+public /* not final for android.system.StructStatVfs */ class StructStatVfs {
   /** File system block size (used for block counts). */
   public final long f_bsize; /*unsigned long*/
 

diff --git a/luni/src/main/java/libcore/io/StructTimeval.java b/luni/src/main/java/libcore/io/StructTimeval.java
deleted file mode 100644
index 0ed3509..0000000
--- a/luni/src/main/java/libcore/io/StructTimeval.java
+++ /dev/null

@@ -1,48 +0,0 @@
-/*
- * Copyright (C) 2011 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package libcore.io;
-
-/**
- * Corresponds to C's {@code struct timeval} from
- * <a href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_time.h.html">&lt;sys/time.h&gt;</a>
- */
-public final class StructTimeval {
-    /** Seconds. */
-    public final long tv_sec;
-
-    /** Microseconds. */
-    public final long tv_usec;
-
-    private StructTimeval(long tv_sec, long tv_usec) {
-        this.tv_sec = tv_sec;
-        this.tv_usec = tv_usec;
-    }
-
-    public static StructTimeval fromMillis(long millis) {
-        long tv_sec = millis / 1000;
-        long tv_usec = (millis - (tv_sec * 1000)) * 1000;
-        return new StructTimeval(tv_sec, tv_usec);
-    }
-
-    public long toMillis() {
-        return (tv_sec * 1000) + (tv_usec / 1000);
-    }
-
-    @Override public String toString() {
-        return "StructTimeval[tv_sec=" + tv_sec + ",tv_usec=" + tv_usec + "]";
-    }
-}

diff --git a/luni/src/main/java/libcore/util/ZoneInfoDB.java b/luni/src/main/java/libcore/util/ZoneInfoDB.java
index 10e3900..7ff377c 100644
--- a/luni/src/main/java/libcore/util/ZoneInfoDB.java
+++ b/luni/src/main/java/libcore/util/ZoneInfoDB.java

@@ -16,6 +16,7 @@
 
 package libcore.util;
 
+import android.system.ErrnoException;
 import java.io.IOException;
 import java.io.RandomAccessFile;
 import java.nio.ByteBuffer;
@@ -27,7 +28,6 @@
 import java.util.List;
 import java.util.TimeZone;
 import libcore.io.BufferIterator;
-import libcore.io.ErrnoException;
 import libcore.io.IoUtils;
 import libcore.io.MemoryMappedFile;
 

diff --git a/luni/src/main/native/libcore_io_Posix.cpp b/luni/src/main/native/libcore_io_Posix.cpp
index 65ee36f..7fcec29 100644
--- a/luni/src/main/native/libcore_io_Posix.cpp
+++ b/luni/src/main/native/libcore_io_Posix.cpp

@@ -1025,7 +1025,7 @@
     static jfieldID eventsFid = env->GetFieldID(JniConstants::structPollfdClass, "events", "S");
     static jfieldID reventsFid = env->GetFieldID(JniConstants::structPollfdClass, "revents", "S");
 
-    // Turn the Java libcore.io.StructPollfd[] into a C++ struct pollfd[].
+    // Turn the Java android.system.StructPollfd[] into a C++ struct pollfd[].
     size_t arrayLength = env->GetArrayLength(javaStructs);
     UniquePtr<struct pollfd[]> fds(new struct pollfd[arrayLength]);
     memset(fds.get(), 0, sizeof(struct pollfd) * arrayLength);
@@ -1057,7 +1057,7 @@
         return -1;
     }
 
-    // Update the revents fields in the Java libcore.io.StructPollfd[].
+    // Update the revents fields in the Java android.system.StructPollfd[].
     for (size_t i = 0; i < count; ++i) {
         ScopedLocalRef<jobject> javaStruct(env, env->GetObjectArrayElement(javaStructs, i));
         if (javaStruct.get() == NULL) {
@@ -1493,14 +1493,14 @@
     NATIVE_METHOD(Posix, fchown, "(Ljava/io/FileDescriptor;II)V"),
     NATIVE_METHOD(Posix, fcntlVoid, "(Ljava/io/FileDescriptor;I)I"),
     NATIVE_METHOD(Posix, fcntlLong, "(Ljava/io/FileDescriptor;IJ)I"),
-    NATIVE_METHOD(Posix, fcntlFlock, "(Ljava/io/FileDescriptor;ILlibcore/io/StructFlock;)I"),
+    NATIVE_METHOD(Posix, fcntlFlock, "(Ljava/io/FileDescriptor;ILandroid/system/StructFlock;)I"),
     NATIVE_METHOD(Posix, fdatasync, "(Ljava/io/FileDescriptor;)V"),
-    NATIVE_METHOD(Posix, fstat, "(Ljava/io/FileDescriptor;)Llibcore/io/StructStat;"),
-    NATIVE_METHOD(Posix, fstatvfs, "(Ljava/io/FileDescriptor;)Llibcore/io/StructStatVfs;"),
+    NATIVE_METHOD(Posix, fstat, "(Ljava/io/FileDescriptor;)Landroid/system/StructStat;"),
+    NATIVE_METHOD(Posix, fstatvfs, "(Ljava/io/FileDescriptor;)Landroid/system/StructStatVfs;"),
     NATIVE_METHOD(Posix, fsync, "(Ljava/io/FileDescriptor;)V"),
     NATIVE_METHOD(Posix, ftruncate, "(Ljava/io/FileDescriptor;J)V"),
     NATIVE_METHOD(Posix, gai_strerror, "(I)Ljava/lang/String;"),
-    NATIVE_METHOD(Posix, getaddrinfo, "(Ljava/lang/String;Llibcore/io/StructAddrinfo;)[Ljava/net/InetAddress;"),
+    NATIVE_METHOD(Posix, getaddrinfo, "(Ljava/lang/String;Landroid/system/StructAddrinfo;)[Ljava/net/InetAddress;"),
     NATIVE_METHOD(Posix, getegid, "()I"),
     NATIVE_METHOD(Posix, geteuid, "()I"),
     NATIVE_METHOD(Posix, getgid, "()I"),
@@ -1509,27 +1509,27 @@
     NATIVE_METHOD(Posix, getpeername, "(Ljava/io/FileDescriptor;)Ljava/net/SocketAddress;"),
     NATIVE_METHOD(Posix, getpid, "()I"),
     NATIVE_METHOD(Posix, getppid, "()I"),
-    NATIVE_METHOD(Posix, getpwnam, "(Ljava/lang/String;)Llibcore/io/StructPasswd;"),
-    NATIVE_METHOD(Posix, getpwuid, "(I)Llibcore/io/StructPasswd;"),
+    NATIVE_METHOD(Posix, getpwnam, "(Ljava/lang/String;)Landroid/system/StructPasswd;"),
+    NATIVE_METHOD(Posix, getpwuid, "(I)Landroid/system/StructPasswd;"),
     NATIVE_METHOD(Posix, getsockname, "(Ljava/io/FileDescriptor;)Ljava/net/SocketAddress;"),
     NATIVE_METHOD(Posix, getsockoptByte, "(Ljava/io/FileDescriptor;II)I"),
     NATIVE_METHOD(Posix, getsockoptInAddr, "(Ljava/io/FileDescriptor;II)Ljava/net/InetAddress;"),
     NATIVE_METHOD(Posix, getsockoptInt, "(Ljava/io/FileDescriptor;II)I"),
-    NATIVE_METHOD(Posix, getsockoptLinger, "(Ljava/io/FileDescriptor;II)Llibcore/io/StructLinger;"),
-    NATIVE_METHOD(Posix, getsockoptTimeval, "(Ljava/io/FileDescriptor;II)Llibcore/io/StructTimeval;"),
-    NATIVE_METHOD(Posix, getsockoptUcred, "(Ljava/io/FileDescriptor;II)Llibcore/io/StructUcred;"),
+    NATIVE_METHOD(Posix, getsockoptLinger, "(Ljava/io/FileDescriptor;II)Landroid/system/StructLinger;"),
+    NATIVE_METHOD(Posix, getsockoptTimeval, "(Ljava/io/FileDescriptor;II)Landroid/system/StructTimeval;"),
+    NATIVE_METHOD(Posix, getsockoptUcred, "(Ljava/io/FileDescriptor;II)Landroid/system/StructUcred;"),
     NATIVE_METHOD(Posix, gettid, "()I"),
     NATIVE_METHOD(Posix, getuid, "()I"),
     NATIVE_METHOD(Posix, if_indextoname, "(I)Ljava/lang/String;"),
     NATIVE_METHOD(Posix, inet_pton, "(ILjava/lang/String;)Ljava/net/InetAddress;"),
     NATIVE_METHOD(Posix, ioctlInetAddress, "(Ljava/io/FileDescriptor;ILjava/lang/String;)Ljava/net/InetAddress;"),
-    NATIVE_METHOD(Posix, ioctlInt, "(Ljava/io/FileDescriptor;ILlibcore/util/MutableInt;)I"),
+    NATIVE_METHOD(Posix, ioctlInt, "(Ljava/io/FileDescriptor;ILandroid/util/MutableInt;)I"),
     NATIVE_METHOD(Posix, isatty, "(Ljava/io/FileDescriptor;)Z"),
     NATIVE_METHOD(Posix, kill, "(II)V"),
     NATIVE_METHOD(Posix, lchown, "(Ljava/lang/String;II)V"),
     NATIVE_METHOD(Posix, listen, "(Ljava/io/FileDescriptor;I)V"),
     NATIVE_METHOD(Posix, lseek, "(Ljava/io/FileDescriptor;JI)J"),
-    NATIVE_METHOD(Posix, lstat, "(Ljava/lang/String;)Llibcore/io/StructStat;"),
+    NATIVE_METHOD(Posix, lstat, "(Ljava/lang/String;)Landroid/system/StructStat;"),
     NATIVE_METHOD(Posix, mincore, "(JJ[B)V"),
     NATIVE_METHOD(Posix, mkdir, "(Ljava/lang/String;I)V"),
     NATIVE_METHOD(Posix, mkfifo, "(Ljava/lang/String;I)V"),
@@ -1540,7 +1540,7 @@
     NATIVE_METHOD(Posix, munmap, "(JJ)V"),
     NATIVE_METHOD(Posix, open, "(Ljava/lang/String;II)Ljava/io/FileDescriptor;"),
     NATIVE_METHOD(Posix, pipe, "()[Ljava/io/FileDescriptor;"),
-    NATIVE_METHOD(Posix, poll, "([Llibcore/io/StructPollfd;I)I"),
+    NATIVE_METHOD(Posix, poll, "([Landroid/system/StructPollfd;I)I"),
     NATIVE_METHOD(Posix, posix_fallocate, "(Ljava/io/FileDescriptor;JJ)V"),
     NATIVE_METHOD(Posix, preadBytes, "(Ljava/io/FileDescriptor;Ljava/lang/Object;IIJ)I"),
     NATIVE_METHOD(Posix, pwriteBytes, "(Ljava/io/FileDescriptor;Ljava/lang/Object;IIJ)I"),
@@ -1550,7 +1550,7 @@
     NATIVE_METHOD(Posix, recvfromBytes, "(Ljava/io/FileDescriptor;Ljava/lang/Object;IIILjava/net/InetSocketAddress;)I"),
     NATIVE_METHOD(Posix, remove, "(Ljava/lang/String;)V"),
     NATIVE_METHOD(Posix, rename, "(Ljava/lang/String;Ljava/lang/String;)V"),
-    NATIVE_METHOD(Posix, sendfile, "(Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;Llibcore/util/MutableLong;J)J"),
+    NATIVE_METHOD(Posix, sendfile, "(Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;Landroid/util/MutableLong;J)J"),
     NATIVE_METHOD(Posix, sendtoBytes, "(Ljava/io/FileDescriptor;Ljava/lang/Object;IIILjava/net/InetAddress;I)I"),
     NATIVE_METHOD(Posix, setegid, "(I)V"),
     NATIVE_METHOD(Posix, setenv, "(Ljava/lang/String;Ljava/lang/String;Z)V"),
@@ -1561,16 +1561,16 @@
     NATIVE_METHOD(Posix, setsockoptIfreq, "(Ljava/io/FileDescriptor;IILjava/lang/String;)V"),
     NATIVE_METHOD(Posix, setsockoptInt, "(Ljava/io/FileDescriptor;III)V"),
     NATIVE_METHOD(Posix, setsockoptIpMreqn, "(Ljava/io/FileDescriptor;III)V"),
-    NATIVE_METHOD(Posix, setsockoptGroupReq, "(Ljava/io/FileDescriptor;IILlibcore/io/StructGroupReq;)V"),
-    NATIVE_METHOD(Posix, setsockoptGroupSourceReq, "(Ljava/io/FileDescriptor;IILlibcore/io/StructGroupSourceReq;)V"),
-    NATIVE_METHOD(Posix, setsockoptLinger, "(Ljava/io/FileDescriptor;IILlibcore/io/StructLinger;)V"),
-    NATIVE_METHOD(Posix, setsockoptTimeval, "(Ljava/io/FileDescriptor;IILlibcore/io/StructTimeval;)V"),
+    NATIVE_METHOD(Posix, setsockoptGroupReq, "(Ljava/io/FileDescriptor;IILandroid/system/StructGroupReq;)V"),
+    NATIVE_METHOD(Posix, setsockoptGroupSourceReq, "(Ljava/io/FileDescriptor;IILandroid/system/StructGroupSourceReq;)V"),
+    NATIVE_METHOD(Posix, setsockoptLinger, "(Ljava/io/FileDescriptor;IILandroid/system/StructLinger;)V"),
+    NATIVE_METHOD(Posix, setsockoptTimeval, "(Ljava/io/FileDescriptor;IILandroid/system/StructTimeval;)V"),
     NATIVE_METHOD(Posix, setuid, "(I)V"),
     NATIVE_METHOD(Posix, shutdown, "(Ljava/io/FileDescriptor;I)V"),
     NATIVE_METHOD(Posix, socket, "(III)Ljava/io/FileDescriptor;"),
     NATIVE_METHOD(Posix, socketpair, "(IIILjava/io/FileDescriptor;Ljava/io/FileDescriptor;)V"),
-    NATIVE_METHOD(Posix, stat, "(Ljava/lang/String;)Llibcore/io/StructStat;"),
-    NATIVE_METHOD(Posix, statvfs, "(Ljava/lang/String;)Llibcore/io/StructStatVfs;"),
+    NATIVE_METHOD(Posix, stat, "(Ljava/lang/String;)Landroid/system/StructStat;"),
+    NATIVE_METHOD(Posix, statvfs, "(Ljava/lang/String;)Landroid/system/StructStatVfs;"),
     NATIVE_METHOD(Posix, strerror, "(I)Ljava/lang/String;"),
     NATIVE_METHOD(Posix, strsignal, "(I)Ljava/lang/String;"),
     NATIVE_METHOD(Posix, symlink, "(Ljava/lang/String;Ljava/lang/String;)V"),
@@ -1578,9 +1578,9 @@
     NATIVE_METHOD(Posix, tcdrain, "(Ljava/io/FileDescriptor;)V"),
     NATIVE_METHOD(Posix, tcsendbreak, "(Ljava/io/FileDescriptor;I)V"),
     NATIVE_METHOD(Posix, umaskImpl, "(I)I"),
-    NATIVE_METHOD(Posix, uname, "()Llibcore/io/StructUtsname;"),
+    NATIVE_METHOD(Posix, uname, "()Landroid/system/StructUtsname;"),
     NATIVE_METHOD(Posix, unsetenv, "(Ljava/lang/String;)V"),
-    NATIVE_METHOD(Posix, waitpid, "(ILlibcore/util/MutableInt;I)I"),
+    NATIVE_METHOD(Posix, waitpid, "(ILandroid/util/MutableInt;I)I"),
     NATIVE_METHOD(Posix, writeBytes, "(Ljava/io/FileDescriptor;Ljava/lang/Object;II)I"),
     NATIVE_METHOD(Posix, writev, "(Ljava/io/FileDescriptor;[Ljava/lang/Object;[I[I)I"),
 };

diff --git a/luni/src/test/java/libcore/io/OsTest.java b/luni/src/test/java/libcore/io/OsTest.java
index 624c119..cf28122 100644
--- a/luni/src/test/java/libcore/io/OsTest.java
+++ b/luni/src/test/java/libcore/io/OsTest.java

@@ -16,6 +16,7 @@
 
 package libcore.io;
 
+import android.system.StructUcred;
 import java.io.File;
 import java.io.FileDescriptor;
 import java.io.FileInputStream;
@@ -26,8 +27,7 @@
 import java.net.SocketAddress;
 import java.util.Locale;
 import junit.framework.TestCase;
-
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 public class OsTest extends TestCase {
   public void testIsSocket() throws Exception {

diff --git a/luni/src/test/java/libcore/java/nio/channels/FileIOInterruptTest.java b/luni/src/test/java/libcore/java/nio/channels/FileIOInterruptTest.java
index 2ac8827..c06df04 100644
--- a/luni/src/test/java/libcore/java/nio/channels/FileIOInterruptTest.java
+++ b/luni/src/test/java/libcore/java/nio/channels/FileIOInterruptTest.java

@@ -17,19 +17,19 @@
 
 import junit.framework.TestCase;
 
+import android.system.ErrnoException;
+import android.system.OsConstants;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
-import java.io.IOException;
 import java.io.InterruptedIOException;
+import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.AsynchronousCloseException;
 import java.nio.channels.ClosedByInterruptException;
 import java.nio.channels.ClosedChannelException;
 import java.nio.channels.FileChannel;
-import libcore.io.ErrnoException;
 import libcore.io.Libcore;
-import libcore.io.OsConstants;
 
 import static libcore.io.IoUtils.closeQuietly;
 

diff --git a/luni/src/test/java/libcore/java/nio/channels/SelectorTest.java b/luni/src/test/java/libcore/java/nio/channels/SelectorTest.java
index 24751c2..c5f449e 100644
--- a/luni/src/test/java/libcore/java/nio/channels/SelectorTest.java
+++ b/luni/src/test/java/libcore/java/nio/channels/SelectorTest.java

@@ -15,6 +15,7 @@
  */
 package libcore.java.nio.channels;
 
+import android.system.OsConstants;
 import java.io.IOException;
 import java.net.InetSocketAddress;
 import java.net.ServerSocket;
@@ -26,9 +27,8 @@
 import java.nio.channels.SocketChannel;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
-import libcore.io.Libcore;
-import libcore.io.OsConstants;
 import junit.framework.TestCase;
+import libcore.io.Libcore;
 import tests.net.StuckServer;
 
 public class SelectorTest extends TestCase {

diff --git a/luni/src/test/java/libcore/java/nio/channels/SocketChannelTest.java b/luni/src/test/java/libcore/java/nio/channels/SocketChannelTest.java
index bd23b3f..6bba862 100644
--- a/luni/src/test/java/libcore/java/nio/channels/SocketChannelTest.java
+++ b/luni/src/test/java/libcore/java/nio/channels/SocketChannelTest.java

@@ -36,7 +36,7 @@
 
 import tests.io.MockOs;
 
-import static libcore.io.OsConstants.*;
+import static android.system.OsConstants.*;
 
 public class SocketChannelTest extends junit.framework.TestCase {
 

diff --git a/support/src/test/java/tests/io/MockOs.java b/support/src/test/java/tests/io/MockOs.java
index d7e284f..b1c6cee 100644
--- a/support/src/test/java/tests/io/MockOs.java
+++ b/support/src/test/java/tests/io/MockOs.java

@@ -16,6 +16,8 @@
 
 package tests.io;
 
+import android.system.ErrnoException;
+import android.system.OsConstants;
 import java.lang.reflect.InvocationHandler;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
@@ -24,10 +26,8 @@
 import java.util.Deque;
 import java.util.HashMap;
 import java.util.Map;
-import libcore.io.ErrnoException;
 import libcore.io.Libcore;
 import libcore.io.Os;
-import libcore.io.OsConstants;
 
 /**
  * A mocking interceptor that wraps another {@link Os} to add faults. This can