diff --git a/epf/Cell.cpp b/epf/Cell.cpp
index fa5a8cc..400493a 100644
--- a/epf/Cell.cpp
+++ b/epf/Cell.cpp
@@ -24,9 +24,7 @@ void Cell::initialize()
     m_buf = m_writer->bufferCache().fetch();
     m_pos = m_buf->data();
 
-    // The end position is one less than the buffer size to allow for
-    // speculative writes into the cell.  See FileProcessor for details.
-    m_endPos = m_pos + m_pointSize * ((BufSize / m_pointSize) - 1);
+    m_endPos = m_pos + m_pointSize * (BufSize / m_pointSize);
 }
 
 void Cell::write()
@@ -43,7 +41,7 @@ void Cell::write()
 void Cell::advance()
 {
     m_pos += m_pointSize;
-    if (m_pos > m_endPos)
+    if (m_pos >= m_endPos)
     {
         write();
         initialize();
diff --git a/epf/Epf.cpp b/epf/Epf.cpp
index 1dce392..3aed693 100644
--- a/epf/Epf.cpp
+++ b/epf/Epf.cpp
@@ -158,8 +158,6 @@ void Epf::run(const std::vector<std::string>& options)
     // Make a writer with 4 threads.
     m_writer.reset(new Writer(m_outputDir, 4));
 
-    std::vector<std::unique_ptr<FileProcessor>> processors;
-
     // Sort file infos so the largest files come first. This helps to make sure we don't delay
     // processing big files that take the longest (use threads more efficiently).
     std::sort(fileInfos.begin(), fileInfos.end(), [](const FileInfo& f1, const FileInfo& f2)
@@ -167,11 +165,12 @@ void Epf::run(const std::vector<std::string>& options)
     // Add the files to the processing pool
     for (const FileInfo& fi : fileInfos)
     {
-        std::unique_ptr<FileProcessor> fp(
-            new FileProcessor(fi, layout->pointSize(), m_grid, m_writer.get()));
-        std::function<void()> processor = std::bind(&FileProcessor::operator(), fp.get());
-        m_pool.add(processor);
-        processors.push_back(std::move(fp));
+        int pointSize = layout->pointSize();
+        m_pool.add([&fi, pointSize, this]()
+        {
+            FileProcessor fp(fi, pointSize, m_grid, m_writer.get());
+            fp.run();
+        });
     }
 
     // Wait for  all the processors to finish and restart.
diff --git a/epf/FileProcessor.cpp b/epf/FileProcessor.cpp
index d045301..ac720c9 100644
--- a/epf/FileProcessor.cpp
+++ b/epf/FileProcessor.cpp
@@ -30,7 +30,7 @@ FileProcessor::FileProcessor(const FileInfo& fi, size_t pointSize, const Grid& g
     m_fi(fi), m_cellMgr(pointSize, writer), m_grid(grid), m_cnt(++m_totalCnt)
 {}
 
-void FileProcessor::operator()()
+void FileProcessor::run()
 {
     Options opts;
     opts.add("filename", m_fi.filename);
diff --git a/epf/FileProcessor.hpp b/epf/FileProcessor.hpp
index a25b714..266a8c6 100644
--- a/epf/FileProcessor.hpp
+++ b/epf/FileProcessor.hpp
@@ -29,7 +29,7 @@ class FileProcessor
     FileProcessor(const FileInfo& fi, size_t pointSize, const Grid& grid, Writer *writer);
 
     Cell *getCell(const VoxelKey& key);
-    void operator()();
+    void run();
 
 private:
     FileInfo m_fi;
diff --git a/epf/Writer.cpp b/epf/Writer.cpp
index a96e0c3..563fe89 100644
--- a/epf/Writer.cpp
+++ b/epf/Writer.cpp
@@ -26,12 +26,6 @@ namespace ept2
 namespace epf
 {
 
-struct WriteData
-{
-    VoxelKey key;
-    DataVecPtr data;
-};
-
 Writer::Writer(const std::string& directory, int numThreads) :
     m_directory(directory), m_pool(numThreads), m_stop(false)
 {
@@ -114,6 +108,9 @@ void Writer::run()
         // Remove the key from the active key list.
         std::ofstream out(path(wd.key), std::ios::app | std::ios::binary);
         out.write(reinterpret_cast<const char *>(wd.data->data()), wd.data->size());
+        out.close();
+        if (!out)
+            throw Error("Failure writing to '" + path(wd.key) + "'.");
         m_bufferCache.replace(std::move(wd.data));
 
         std::lock_guard<std::mutex> lock(m_mutex);
diff --git a/epf/Writer.hpp b/epf/Writer.hpp
index cc7c196..2b4f102 100644
--- a/epf/Writer.hpp
+++ b/epf/Writer.hpp
@@ -35,7 +35,7 @@ class Writer
     struct WriteData
     {
         VoxelKey key;
-        std::unique_ptr<std::vector<uint8_t>> data;
+        DataVecPtr data;
     };
 
 public: