diff --git a/libjava/ChangeLog b/libjava/ChangeLog
index 375f109b6fc..b3e347fde2e 100644
--- a/libjava/ChangeLog
+++ b/libjava/ChangeLog
@@ -1,3 +1,17 @@
+2004-07-17  Mark Wielaard  <mark@klomp.org>
+
+	* gnu/java/nio/channels/FileChannelImpl.java (truncate): Only truncate
+	when size is smaller.
+	* java/io/RandomAccessFile.java (setLength): Use truncate for
+	shrinking the file and seek plus write for expanding the file.
+
+2004-07-17  Michael Koch  <konqueror@gmx.de>
+
+	* gnu/java/nio/channels/natFileChannelPosix.cc
+	(implTruncate): Always save current position. Only reposition file
+	pointer to where we started if not beyond new lenght. Reposition file
+	pointer to file length if it points beyond the end of file.
+
 2004-07-17  Mark Wielaard  <mark@klomp.org>
 
 	* javax/swing/Box.java: Put FIXME comment above class declaration.
diff --git a/libjava/gnu/java/nio/channels/FileChannelImpl.java b/libjava/gnu/java/nio/channels/FileChannelImpl.java
index 8b3d0fc86b3..678e10f2349 100644
--- a/libjava/gnu/java/nio/channels/FileChannelImpl.java
+++ b/libjava/gnu/java/nio/channels/FileChannelImpl.java
@@ -422,7 +422,9 @@ public final class FileChannelImpl extends FileChannel
     if ((mode & WRITE) == 0)
        throw new NonWritableChannelException ();
 
-    implTruncate (size);
+    if (size < size ())
+      implTruncate (size);
+
     return this;
   }
 }
diff --git a/libjava/gnu/java/nio/channels/natFileChannelPosix.cc b/libjava/gnu/java/nio/channels/natFileChannelPosix.cc
index b8f99378834..a2c1c7962b0 100644
--- a/libjava/gnu/java/nio/channels/natFileChannelPosix.cc
+++ b/libjava/gnu/java/nio/channels/natFileChannelPosix.cc
@@ -274,7 +274,10 @@ FileChannelImpl::implTruncate (jlong size)
     }
   else
     {
-      if (::ftruncate (fd, (off_t) pos))
+      if (::ftruncate (fd, (off_t) size))
+	throw new IOException (JvNewStringLatin1 (strerror (errno)));
+      if (pos > size
+	  && ::lseek (fd, (off_t) size, SEEK_SET) == -1)
 	throw new IOException (JvNewStringLatin1 (strerror (errno)));
       pos = size;
     }
diff --git a/libjava/java/io/RandomAccessFile.java b/libjava/java/io/RandomAccessFile.java
index c20549c12df..7907d46f2fd 100644
--- a/libjava/java/io/RandomAccessFile.java
+++ b/libjava/java/io/RandomAccessFile.java
@@ -194,12 +194,14 @@ public class RandomAccessFile implements DataOutput, DataInput
   }
 
   /**
-   * This method sets the length of the file to the specified length.  If
-   * the currently length of the file is longer than the specified length,
-   * then the file is truncated to the specified length.  If the current
-   * length of the file is shorter than the specified length, the file
-   * is extended with bytes of an undefined value.
-   *  <p>
+   * This method sets the length of the file to the specified length.
+   * If the currently length of the file is longer than the specified
+   * length, then the file is truncated to the specified length (the
+   * file position is set to the end of file in this case).  If the
+   * current length of the file is shorter than the specified length,
+   * the file is extended with bytes of an undefined value (the file
+   * position is unchanged in this case).
+   * <p>
    * The file must be open for write access for this operation to succeed.
    *
    * @param newlen The new length of the file
@@ -208,7 +210,19 @@ public class RandomAccessFile implements DataOutput, DataInput
    */
   public void setLength (long newLen) throws IOException
   {
-    ch.truncate (newLen);
+    // FIXME: Extending a file should probably be done by one method call.
+
+    // FileChannel.truncate() can only shrink a file.
+    // To expand it we need to seek forward and write at least one byte.
+    if (newLen < length())
+      ch.truncate (newLen);
+    else if (newLen > length())
+      {
+	long pos = getFilePointer();
+	seek(newLen - 1);
+	write(0);
+	seek(pos);
+      }
   }
 
   /**