diff --git a/src/juce_core/io/files/juce_File.cpp b/src/juce_core/io/files/juce_File.cpp
index 99eb020894..dd75da475a 100644
--- a/src/juce_core/io/files/juce_File.cpp
+++ b/src/juce_core/io/files/juce_File.cpp
@@ -889,7 +889,7 @@ FileOutputStream* File::createOutputStream (const int bufferSize) const throw()
 {
     FileOutputStream* const out = new FileOutputStream (*this, bufferSize);
 
-    if (out->areAnyErrors())
+    if (out->failedToOpen())
     {
         delete out;
         return 0;
diff --git a/src/juce_core/io/files/juce_FileInputStream.cpp b/src/juce_core/io/files/juce_FileInputStream.cpp
index 29ff35190f..d10858cd19 100644
--- a/src/juce_core/io/files/juce_FileInputStream.cpp
+++ b/src/juce_core/io/files/juce_FileInputStream.cpp
@@ -37,10 +37,10 @@ BEGIN_JUCE_NAMESPACE
 
 
 //==============================================================================
-void* juce_fileOpen (const String& path, bool forWriting);
-void juce_fileClose (void* handle);
-int juce_fileRead (void* handle, void* buffer, int size);
-int64 juce_fileSetPosition (void* handle, int64 pos);
+void* juce_fileOpen (const String& path, bool forWriting) throw();
+void juce_fileClose (void* handle) throw();
+int juce_fileRead (void* handle, void* buffer, int size) throw();
+int64 juce_fileSetPosition (void* handle, int64 pos) throw();
 
 
 //==============================================================================
diff --git a/src/juce_core/io/files/juce_FileOutputStream.cpp b/src/juce_core/io/files/juce_FileOutputStream.cpp
index 543864adda..7719e1cabd 100644
--- a/src/juce_core/io/files/juce_FileOutputStream.cpp
+++ b/src/juce_core/io/files/juce_FileOutputStream.cpp
@@ -33,15 +33,14 @@
 
 BEGIN_JUCE_NAMESPACE
 
-
 #include "juce_FileOutputStream.h"
 
-void* juce_fileOpen (const String& path, bool forWriting);
-void juce_fileClose (void* handle);
-int juce_fileWrite (void* handle, const void* buffer, int size);
-void juce_fileFlush (void* handle);
-int64 juce_fileGetPosition (void* handle);
-int64 juce_fileSetPosition (void* handle, int64 pos);
+void* juce_fileOpen (const String& path, bool forWriting) throw();
+void juce_fileClose (void* handle) throw();
+int juce_fileWrite (void* handle, const void* buffer, int size) throw();
+void juce_fileFlush (void* handle) throw();
+int64 juce_fileGetPosition (void* handle) throw();
+int64 juce_fileSetPosition (void* handle, int64 pos) throw();
 
 
 //==============================================================================
@@ -65,7 +64,7 @@ FileOutputStream::FileOutputStream (const File& f,
         }
     }
 
-    buffer = (char*) juce_malloc (jmax (bufferSize_, 64));
+    buffer = (char*) juce_malloc (jmax (bufferSize_, 16));
 }
 
 FileOutputStream::~FileOutputStream()
@@ -76,16 +75,6 @@ FileOutputStream::~FileOutputStream()
     juce_free (buffer);
 }
 
-const File FileOutputStream::getFile() const
-{
-    return file;
-}
-
-bool FileOutputStream::areAnyErrors()
-{
-    return fileHandle == 0;
-}
-
 int64 FileOutputStream::getPosition()
 {
     return currentPosition;
@@ -113,7 +102,7 @@ void FileOutputStream::flush()
     juce_fileFlush (fileHandle);
 }
 
-bool FileOutputStream::write (const void* src, int numBytes)
+bool FileOutputStream::write (const void* const src, const int numBytes)
 {
     if (bytesInBuffer + numBytes < bufferSize)
     {
diff --git a/src/juce_core/io/files/juce_FileOutputStream.h b/src/juce_core/io/files/juce_FileOutputStream.h
index 5928a55688..b6b55ec649 100644
--- a/src/juce_core/io/files/juce_FileOutputStream.h
+++ b/src/juce_core/io/files/juce_FileOutputStream.h
@@ -49,7 +49,7 @@ public:
     /** Creates a FileOutputStream.
 
         If the file doesn't exist, it will first be created. If the file can't be
-        created or opened, the areAnyErrors() method will return
+        created or opened, the failedToOpen() method will return
         true.
 
         If the file already exists when opened, the stream's write-postion will
@@ -67,7 +67,13 @@ public:
     ~FileOutputStream();
 
     //==============================================================================
-    const File getFile() const;
+    /** Returns the file that this stream is writing to.
+    */
+    const File& getFile() const throw()                 { return file; }
+
+    /** Returns true if the stream couldn't be opened for some reason.
+    */
+    bool failedToOpen() const throw()                   { return fileHandle == 0; }
 
     //==============================================================================
     void flush();
@@ -75,8 +81,6 @@ public:
     bool setPosition (int64 pos);
     bool write (const void* data, int numBytes);
 
-    bool areAnyErrors();
-
 
     //==============================================================================
     juce_UseDebuggingNewOperator