3 files changed, 15 insertions, 2 deletions
diff --git a/src/lib/utils/data_src.cpp b/src/lib/utils/data_src.cpp
index 0c06f2fe4..7da94d7c0 100644
--- a/src/lib/utils/data_src.cpp
+++ b/src/lib/utils/data_src.cpp
@@ -8,9 +8,12 @@
 
 #include <botan/data_src.h>
 #include <botan/exceptn.h>
-#include <fstream>
 #include <algorithm>
 
+#if defined(BOTAN_TARGET_OS_HAS_FILESYSTEM)
+  #include <fstream>
+#endif
+
 namespace Botan {
 
 /*
@@ -98,6 +101,8 @@ DataSource_Memory::DataSource_Memory(const std::string& in) :
    {
    }
 
+#if defined(BOTAN_TARGET_OS_HAS_FILESYSTEM)
+
 /*
 * Read from a stream
 */
@@ -209,4 +214,6 @@ DataSource_Stream::~DataSource_Stream()
    delete m_source_p;
    }
 
+#endif
+
 }
diff --git a/src/lib/utils/data_src.h b/src/lib/utils/data_src.h
index 6a100ce63..b24fd75a4 100644
--- a/src/lib/utils/data_src.h
+++ b/src/lib/utils/data_src.h
@@ -138,6 +138,8 @@ class BOTAN_DLL DataSource_Memory : public DataSource
       size_t m_offset;
    };
 
+#if defined(BOTAN_TARGET_OS_HAS_FILESYSTEM)
+
 /**
 * This class represents a Stream-Based DataSource.
 */
@@ -175,6 +177,8 @@ class BOTAN_DLL DataSource_Stream : public DataSource
       size_t m_total_read;
    };
 
+#endif
+
 }
 
 #endif
diff --git a/src/lib/utils/os_utils.cpp b/src/lib/utils/os_utils.cpp
index 2f17da952..56ec59cc0 100644
--- a/src/lib/utils/os_utils.cpp
+++ b/src/lib/utils/os_utils.cpp
@@ -33,8 +33,10 @@ uint32_t get_process_id()
    return ::getpid();
 #elif defined(BOTAN_TARGET_OS_IS_WINDOWS) || defined(BOTAN_TARGET_OS_IS_MINGW)
    return ::GetCurrentProcessId();
+#elif defined(BOTAN_TARGET_OS_TYPE_IS_UNIKERNEL)
+   return 0;
 #else
-   throw Exception("get_process_id not supported");
+   #error "Missing get_process_id"
 #endif
    }