uhd: C API wrapper

* multi_usrp, multi_usrp_clock, and associated classes accessible through C
* Added Doxygen documentation explaining structure and API
* Simple RX and TX streaming examples
* Unit tests for different parts of C interface and C++ error conversion

18 files changed, 2952 insertions, 3 deletions

diff --git a/host/lib/CMakeLists.txt b/host/lib/CMakeLists.txt
index 3d4ba8a68..f74af1f29 100644
--- a/host/lib/CMakeLists.txt
+++ b/host/lib/CMakeLists.txt
@@ -96,6 +96,12 @@ LIBUHD_APPEND_SOURCES(
     ${CMAKE_CURRENT_BINARY_DIR}/version.cpp
 )
 
+IF(ENABLE_C_API)
+    LIBUHD_APPEND_SOURCES(
+        ${CMAKE_CURRENT_SOURCE_DIR}/error_c.cpp
+    )
+ENDIF(ENABLE_C_API)
+
 ########################################################################
 # Add DLL resource file to Windows build
 ########################################################################
diff --git a/host/lib/error_c.cpp b/host/lib/error_c.cpp
new file mode 100644
index 000000000..c3a83eec9
--- /dev/null
+++ b/host/lib/error_c.cpp
@@ -0,0 +1,40 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/error.h>
+#include <uhd/exception.hpp>
+
+#define MAP_TO_ERROR(exception_type, error_type) \
+    if (dynamic_cast<const uhd::exception_type*>(e)) return error_type;
+
+uhd_error error_from_uhd_exception(const uhd::exception* e){
+    MAP_TO_ERROR(index_error,           UHD_ERROR_INDEX)
+    MAP_TO_ERROR(key_error,             UHD_ERROR_KEY)
+    MAP_TO_ERROR(not_implemented_error, UHD_ERROR_NOT_IMPLEMENTED)
+    MAP_TO_ERROR(usb_error,             UHD_ERROR_USB)
+    MAP_TO_ERROR(io_error,              UHD_ERROR_IO)
+    MAP_TO_ERROR(os_error,              UHD_ERROR_OS)
+    MAP_TO_ERROR(assertion_error,       UHD_ERROR_ASSERTION)
+    MAP_TO_ERROR(lookup_error,          UHD_ERROR_LOOKUP)
+    MAP_TO_ERROR(type_error,            UHD_ERROR_TYPE)
+    MAP_TO_ERROR(value_error,           UHD_ERROR_VALUE)
+    MAP_TO_ERROR(runtime_error,         UHD_ERROR_RUNTIME)
+    MAP_TO_ERROR(environment_error,     UHD_ERROR_ENVIRONMENT)
+    MAP_TO_ERROR(system_error,          UHD_ERROR_SYSTEM)
+
+    return UHD_ERROR_EXCEPT;
+}
diff --git a/host/lib/types/CMakeLists.txt b/host/lib/types/CMakeLists.txt
index 5e97628f0..d8938c8a8 100644
--- a/host/lib/types/CMakeLists.txt
+++ b/host/lib/types/CMakeLists.txt
@@ -94,3 +94,13 @@ LIBUHD_APPEND_SOURCES(
     ${CMAKE_CURRENT_SOURCE_DIR}/filters.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/byte_vector.cpp
 )
+
+IF(ENABLE_C_API)
+    LIBUHD_APPEND_SOURCES(
+        ${CMAKE_CURRENT_SOURCE_DIR}/metadata_c.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/ranges_c.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/sensors_c.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/tune_c.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/usrp_info_c.cpp
+    )
+ENDIF()
diff --git a/host/lib/types/metadata_c.cpp b/host/lib/types/metadata_c.cpp
new file mode 100644
index 000000000..96f43d140
--- /dev/null
+++ b/host/lib/types/metadata_c.cpp
@@ -0,0 +1,315 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/types/metadata.h>
+
+#include <uhd/types/time_spec.hpp>
+
+#include <string.h>
+
+/*
+ * RX metadata
+ */
+
+uhd_error uhd_rx_metadata_make(
+    uhd_rx_metadata_handle* handle
+){
+    UHD_SAFE_C(
+        *handle = new uhd_rx_metadata_t;
+    )
+}
+
+uhd_error uhd_rx_metadata_free(
+    uhd_rx_metadata_handle* handle
+){
+    UHD_SAFE_C(
+        delete *handle;
+        *handle = NULL;
+    )
+}
+
+uhd_error uhd_rx_metadata_has_time_spec(
+    uhd_rx_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+         *result_out = h->rx_metadata_cpp.has_time_spec;
+    )
+}
+
+uhd_error uhd_rx_metadata_time_spec(
+    uhd_rx_metadata_handle h,
+    time_t *full_secs_out,
+    double *frac_secs_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp = h->rx_metadata_cpp.time_spec;
+        *full_secs_out = time_spec_cpp.get_full_secs();
+        *frac_secs_out = time_spec_cpp.get_frac_secs();
+    )
+}
+
+uhd_error uhd_rx_metadata_more_fragments(
+    uhd_rx_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *result_out = h->rx_metadata_cpp.more_fragments;
+    )
+}
+
+uhd_error uhd_rx_metadata_fragment_offset(
+    uhd_rx_metadata_handle h,
+    size_t *fragment_offset_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *fragment_offset_out = h->rx_metadata_cpp.fragment_offset;
+    )
+}
+
+uhd_error uhd_rx_metadata_start_of_burst(
+    uhd_rx_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *result_out = h->rx_metadata_cpp.start_of_burst;
+    )
+}
+
+uhd_error uhd_rx_metadata_end_of_burst(
+    uhd_rx_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *result_out = h->rx_metadata_cpp.end_of_burst;
+    )
+}
+
+uhd_error uhd_rx_metadata_out_of_sequence(
+    uhd_rx_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *result_out = h->rx_metadata_cpp.out_of_sequence;
+    )
+}
+
+uhd_error uhd_rx_metadata_to_pp_string(
+    uhd_rx_metadata_handle h,
+    char* pp_string_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string pp_string_cpp = h->rx_metadata_cpp.to_pp_string();
+        memset(pp_string_out, '\0', strbuffer_len);
+        strncpy(pp_string_out, pp_string_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_rx_metadata_error_code(
+    uhd_rx_metadata_handle h,
+    uhd_rx_metadata_error_code_t *error_code_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *error_code_out = uhd_rx_metadata_error_code_t(h->rx_metadata_cpp.error_code);
+    )
+}
+
+uhd_error uhd_rx_metadata_strerror(
+    uhd_rx_metadata_handle h,
+    char* strerror_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string strerror_cpp = h->rx_metadata_cpp.strerror();
+        memset(strerror_out, '\0', strbuffer_len);
+        strncpy(strerror_out, strerror_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_rx_metadata_last_error(
+    uhd_rx_metadata_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
+
+/*
+ * TX metadata
+ */
+
+uhd_error uhd_tx_metadata_make(
+    uhd_tx_metadata_handle* handle,
+    bool has_time_spec,
+    time_t full_secs,
+    double frac_secs,
+    bool start_of_burst,
+    bool end_of_burst
+){
+    UHD_SAFE_C(
+        *handle = new uhd_tx_metadata_t;
+        (*handle)->tx_metadata_cpp.has_time_spec = has_time_spec;
+        if(has_time_spec){
+            (*handle)->tx_metadata_cpp.time_spec = uhd::time_spec_t(full_secs, frac_secs);
+        }
+        (*handle)->tx_metadata_cpp.start_of_burst = start_of_burst;
+        (*handle)->tx_metadata_cpp.end_of_burst = end_of_burst;
+    )
+}
+
+uhd_error uhd_tx_metadata_free(
+    uhd_tx_metadata_handle* handle
+){
+    UHD_SAFE_C(
+        delete *handle;
+        *handle = NULL;
+    )
+}
+
+uhd_error uhd_tx_metadata_has_time_spec(
+    uhd_tx_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+         *result_out = h->tx_metadata_cpp.has_time_spec;
+    )
+}
+
+uhd_error uhd_tx_metadata_time_spec(
+    uhd_tx_metadata_handle h,
+    time_t *full_secs_out,
+    double *frac_secs_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp = h->tx_metadata_cpp.time_spec;
+        *full_secs_out = time_spec_cpp.get_full_secs();
+        *frac_secs_out = time_spec_cpp.get_frac_secs();
+    )
+}
+
+uhd_error uhd_tx_metadata_start_of_burst(
+    uhd_tx_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *result_out = h->tx_metadata_cpp.start_of_burst;
+    )
+}
+
+uhd_error uhd_tx_metadata_end_of_burst(
+    uhd_tx_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *result_out = h->tx_metadata_cpp.end_of_burst;
+    )
+}
+
+uhd_error uhd_tx_metadata_last_error(
+    uhd_tx_metadata_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
+
+/*
+ * Async metadata
+ */
+
+uhd_error uhd_async_metadata_make(
+    uhd_async_metadata_handle* handle
+){
+    UHD_SAFE_C(
+        *handle = new uhd_async_metadata_t;
+    )
+}
+
+uhd_error uhd_async_metadata_free(
+    uhd_async_metadata_handle* handle
+){
+    UHD_SAFE_C(
+        delete *handle;
+        *handle = NULL;
+    )
+}
+
+uhd_error uhd_async_metadata_channel(
+    uhd_async_metadata_handle h,
+    size_t *channel_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *channel_out = h->async_metadata_cpp.channel;
+    )
+}
+
+uhd_error uhd_async_metadata_has_time_spec(
+    uhd_async_metadata_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+         *result_out = h->async_metadata_cpp.has_time_spec;
+    )
+}
+
+uhd_error uhd_async_metadata_time_spec(
+    uhd_async_metadata_handle h,
+    time_t *full_secs_out,
+    double *frac_secs_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp = h->async_metadata_cpp.time_spec;
+        *full_secs_out = time_spec_cpp.get_full_secs();
+        *frac_secs_out = time_spec_cpp.get_frac_secs();
+    )
+}
+
+uhd_error uhd_async_metadata_event_code(
+    uhd_async_metadata_handle h,
+    uhd_async_metadata_event_code_t *event_code_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *event_code_out = uhd_async_metadata_event_code_t(h->async_metadata_cpp.event_code);
+    )
+}
+
+uhd_error uhd_async_metadata_user_payload(
+    uhd_async_metadata_handle h,
+    uint32_t user_payload_out[4]
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        memcpy(user_payload_out, h->async_metadata_cpp.user_payload, 4*sizeof(uint32_t));
+    )
+}
+
+uhd_error uhd_async_metadata_last_error(
+    uhd_async_metadata_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
diff --git a/host/lib/types/ranges_c.cpp b/host/lib/types/ranges_c.cpp
new file mode 100644
index 000000000..0c0df24ce
--- /dev/null
+++ b/host/lib/types/ranges_c.cpp
@@ -0,0 +1,162 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/types/ranges.h>
+
+#include <string.h>
+
+/*
+ * uhd::range_t
+ */
+uhd_error uhd_range_to_pp_string(
+    const uhd_range_t *range,
+    char* pp_string_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        uhd::range_t range_cpp = uhd_range_c_to_cpp(range);
+        std::string pp_string_cpp = range_cpp.to_pp_string();
+
+        memset(pp_string_out, '\0', strbuffer_len);
+        strncpy(pp_string_out, pp_string_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd::range_t uhd_range_c_to_cpp(
+    const uhd_range_t *range_c
+){
+    return uhd::range_t(range_c->start, range_c->stop, range_c->step);
+}
+
+void uhd_range_cpp_to_c(
+    const uhd::range_t &range_cpp,
+    uhd_range_t *range_c
+){
+    range_c->start = range_cpp.start();
+    range_c->stop = range_cpp.stop();
+    range_c->step = range_cpp.step();
+}
+
+/*
+ * uhd::meta_range_t
+ */
+uhd_error uhd_meta_range_make(
+    uhd_meta_range_handle* h
+){
+    UHD_SAFE_C(
+        (*h) = new uhd_meta_range_t;
+    )
+}
+
+uhd_error uhd_meta_range_free(
+    uhd_meta_range_handle* h
+){
+    UHD_SAFE_C(
+        delete (*h);
+        (*h) = NULL;
+    )
+}
+
+uhd_error uhd_meta_range_start(
+    uhd_meta_range_handle h,
+    double *start_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *start_out = h->meta_range_cpp.start();
+    )
+}
+
+uhd_error uhd_meta_range_stop(
+    uhd_meta_range_handle h,
+    double *stop_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *stop_out = h->meta_range_cpp.stop();
+    )
+}
+
+uhd_error uhd_meta_range_step(
+    uhd_meta_range_handle h,
+    double *step_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *step_out = h->meta_range_cpp.step();
+    )
+}
+
+uhd_error uhd_meta_range_clip(
+    uhd_meta_range_handle h,
+    double value,
+    bool clip_step,
+    double *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *result_out = h->meta_range_cpp.clip(value, clip_step);
+    )
+}
+
+uhd_error uhd_meta_range_size(
+    uhd_meta_range_handle h,
+    size_t *size_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *size_out = h->meta_range_cpp.size();
+    )
+}
+
+uhd_error uhd_meta_range_push_back(
+    uhd_meta_range_handle h,
+    const uhd_range_t *range
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        h->meta_range_cpp.push_back(uhd_range_c_to_cpp(range));
+    )
+}
+
+uhd_error uhd_meta_range_at(
+    uhd_meta_range_handle h,
+    size_t num,
+    uhd_range_t *range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd_range_cpp_to_c(h->meta_range_cpp.at(num),
+                           range_out);
+    )
+}
+
+uhd_error uhd_meta_range_to_pp_string(
+    uhd_meta_range_handle h,
+    char* pp_string_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string pp_string_cpp = h->meta_range_cpp.to_pp_string();
+        memset(pp_string_out, '\0', strbuffer_len);
+        strncpy(pp_string_out, pp_string_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_meta_range_last_error(
+    uhd_meta_range_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
diff --git a/host/lib/types/sensors_c.cpp b/host/lib/types/sensors_c.cpp
new file mode 100644
index 000000000..f1976c102
--- /dev/null
+++ b/host/lib/types/sensors_c.cpp
@@ -0,0 +1,228 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/types/sensors.h>
+
+#include <boost/lexical_cast.hpp>
+
+#include <stdexcept>
+#include <string.h>
+#include <string>
+
+uhd_error uhd_sensor_value_make_from_bool(
+    uhd_sensor_value_handle* h,
+    const char* name,
+    bool value,
+    const char* utrue,
+    const char* ufalse
+){
+    try{
+        *h = new uhd_sensor_value_t;
+    }
+    catch(...){
+        return UHD_ERROR_UNKNOWN;
+    }
+
+    UHD_SAFE_C_SAVE_ERROR((*h),
+        (*h)->sensor_value_cpp = new uhd::sensor_value_t(name,
+                                                         value,
+                                                         utrue,
+                                                         ufalse);
+    )
+}
+
+uhd_error uhd_sensor_value_make_from_int(
+    uhd_sensor_value_handle* h,
+    const char* name,
+    int value,
+    const char* unit,
+    const char* formatter
+){
+    try{
+        *h = new uhd_sensor_value_t;
+    }
+    catch(...){
+        return UHD_ERROR_UNKNOWN;
+    }
+
+    UHD_SAFE_C_SAVE_ERROR((*h),
+        std::string fmt(formatter);
+        if(fmt.empty()){
+            (*h)->sensor_value_cpp = new uhd::sensor_value_t(name,
+                                                             value,
+                                                             unit);
+        }
+        else{
+            (*h)->sensor_value_cpp = new uhd::sensor_value_t(name,
+                                                             value,
+                                                             unit,
+                                                             fmt);
+        }
+    )
+} 
+
+uhd_error uhd_sensor_value_make_from_realnum(
+    uhd_sensor_value_handle* h,
+    const char* name,
+    double value,
+    const char* unit,
+    const char* formatter
+){
+    try{
+        *h = new uhd_sensor_value_t;
+    }
+    catch(...){
+        return UHD_ERROR_UNKNOWN;
+    }
+
+    UHD_SAFE_C_SAVE_ERROR((*h),
+        std::string fmt(formatter);
+        if(fmt.empty()){
+            (*h)->sensor_value_cpp = new uhd::sensor_value_t(name,
+                                                             value,
+                                                             unit);
+        }
+        else{
+            (*h)->sensor_value_cpp = new uhd::sensor_value_t(name,
+                                                             value,
+                                                             unit,
+                                                             fmt);
+        }
+    )
+}
+
+uhd_error uhd_sensor_value_make_from_string(
+    uhd_sensor_value_handle* h,
+    const char* name,
+    const char* value,
+    const char* unit
+){
+    try{
+        *h = new uhd_sensor_value_t;
+    }
+    catch(...){
+        return UHD_ERROR_UNKNOWN;
+    }
+
+    UHD_SAFE_C_SAVE_ERROR((*h),
+        (*h)->sensor_value_cpp = new uhd::sensor_value_t(name,
+                                                         value,
+                                                         unit);
+    )
+}
+
+uhd_error uhd_sensor_value_free(
+    uhd_sensor_value_handle *h
+){
+    UHD_SAFE_C(
+        delete (*h)->sensor_value_cpp;
+        delete *h;
+        *h = NULL;
+    )
+}
+
+uhd_error uhd_sensor_value_to_bool(
+    uhd_sensor_value_handle h,
+    bool *value_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *value_out = h->sensor_value_cpp->to_bool();
+    )
+}
+
+uhd_error uhd_sensor_value_to_int(
+    uhd_sensor_value_handle h,
+    int *value_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *value_out = h->sensor_value_cpp->to_int();
+    )
+}
+
+uhd_error uhd_sensor_value_to_realnum(
+    uhd_sensor_value_handle h,
+    double *value_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *value_out = h->sensor_value_cpp->to_real();
+    )
+}
+
+uhd_error uhd_sensor_value_name(
+    uhd_sensor_value_handle h,
+    char* name_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        memset(name_out, '\0', strbuffer_len);
+        strncpy(name_out, h->sensor_value_cpp->name.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_sensor_value_value(
+    uhd_sensor_value_handle h,
+    char* value_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        memset(value_out, '\0', strbuffer_len);
+        strncpy(value_out, h->sensor_value_cpp->value.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_sensor_value_unit(
+    uhd_sensor_value_handle h,
+    char* unit_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        memset(unit_out, '\0', strbuffer_len);
+        strncpy(unit_out, h->sensor_value_cpp->unit.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_sensor_value_data_type(
+    uhd_sensor_value_handle h,
+    uhd_sensor_value_data_type_t *data_type_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *data_type_out = uhd_sensor_value_data_type_t(h->sensor_value_cpp->type);
+    )
+}
+
+uhd_error uhd_sensor_value_to_pp_string(
+    uhd_sensor_value_handle h,
+    char* pp_string_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string pp_string_cpp = h->sensor_value_cpp->to_pp_string();
+        memset(pp_string_out, '\0', strbuffer_len);
+        strncpy(pp_string_out, pp_string_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_sensor_value_last_error(
+    uhd_sensor_value_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
diff --git a/host/lib/types/tune_c.cpp b/host/lib/types/tune_c.cpp
new file mode 100644
index 000000000..c62935cb8
--- /dev/null
+++ b/host/lib/types/tune_c.cpp
@@ -0,0 +1,76 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/types/tune_request.h>
+#include <uhd/types/tune_result.h>
+
+#include <boost/format.hpp>
+
+#include <cstdlib>
+#include <cstring>
+#include <iostream>
+
+/*
+ * Tune request
+ */
+
+uhd::tune_request_t uhd_tune_request_c_to_cpp(uhd_tune_request_t *tune_request_c){
+    uhd::tune_request_t tune_request_cpp;
+
+    tune_request_cpp.target_freq = tune_request_c->target_freq;
+    tune_request_cpp.rf_freq_policy = uhd::tune_request_t::policy_t(tune_request_c->rf_freq_policy);
+    tune_request_cpp.rf_freq = tune_request_c->rf_freq;
+    tune_request_cpp.dsp_freq_policy = uhd::tune_request_t::policy_t(tune_request_c->dsp_freq_policy);
+    tune_request_cpp.dsp_freq = tune_request_c->dsp_freq;
+
+    std::string args_cpp = (tune_request_c->args) ? tune_request_c->args : std::string("");
+    tune_request_cpp.args = uhd::device_addr_t(args_cpp);
+
+    return tune_request_cpp;
+}
+
+/*
+ * Tune result
+ */
+
+void uhd_tune_result_to_pp_string(uhd_tune_result_t *tune_result_c,
+                                  char* pp_string_out, size_t strbuffer_len){
+    std::string pp_string_cpp = uhd_tune_result_c_to_cpp(tune_result_c).to_pp_string();
+    memset(pp_string_out, '\0', strbuffer_len);
+    strncpy(pp_string_out, pp_string_cpp.c_str(), strbuffer_len);
+}
+
+uhd::tune_result_t uhd_tune_result_c_to_cpp(uhd_tune_result_t *tune_result_c){
+    uhd::tune_result_t tune_result_cpp;
+
+    tune_result_cpp.clipped_rf_freq = tune_result_c->clipped_rf_freq;
+    tune_result_cpp.target_rf_freq = tune_result_c->target_rf_freq;
+    tune_result_cpp.actual_rf_freq = tune_result_c->actual_rf_freq;
+    tune_result_cpp.target_dsp_freq = tune_result_c->target_dsp_freq;
+    tune_result_cpp.actual_dsp_freq = tune_result_c->actual_dsp_freq;
+
+    return tune_result_cpp;
+}
+
+void uhd_tune_result_cpp_to_c(const uhd::tune_result_t &tune_result_cpp,
+                              uhd_tune_result_t *tune_result_c){
+    tune_result_c->clipped_rf_freq = tune_result_cpp.clipped_rf_freq;
+    tune_result_c->target_rf_freq = tune_result_cpp.target_rf_freq;
+    tune_result_c->actual_rf_freq = tune_result_cpp.actual_rf_freq;
+    tune_result_c->target_dsp_freq = tune_result_cpp.target_dsp_freq;
+    tune_result_c->actual_dsp_freq = tune_result_cpp.actual_dsp_freq;
+}
diff --git a/host/lib/types/usrp_info_c.cpp b/host/lib/types/usrp_info_c.cpp
new file mode 100644
index 000000000..77354d901
--- /dev/null
+++ b/host/lib/types/usrp_info_c.cpp
@@ -0,0 +1,44 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/types/usrp_info.h>
+
+uhd_error uhd_usrp_rx_info_free(uhd_usrp_rx_info_t *rx_info){
+    free(rx_info->mboard_id);
+    free(rx_info->mboard_name);
+    free(rx_info->mboard_serial);
+    free(rx_info->rx_id);
+    free(rx_info->rx_subdev_name);
+    free(rx_info->rx_subdev_spec);
+    free(rx_info->rx_serial);
+    free(rx_info->rx_antenna);
+
+    return UHD_ERROR_NONE;
+}
+
+uhd_error uhd_usrp_tx_info_free(uhd_usrp_tx_info_t *tx_info){
+    free(tx_info->mboard_id);
+    free(tx_info->mboard_name);
+    free(tx_info->mboard_serial);
+    free(tx_info->tx_id);
+    free(tx_info->tx_subdev_name);
+    free(tx_info->tx_subdev_spec);
+    free(tx_info->tx_serial);
+    free(tx_info->tx_antenna);
+
+    return UHD_ERROR_NONE;
+}
diff --git a/host/lib/usrp/CMakeLists.txt b/host/lib/usrp/CMakeLists.txt
index ce913aaf6..e01e5e09d 100644
--- a/host/lib/usrp/CMakeLists.txt
+++ b/host/lib/usrp/CMakeLists.txt
@@ -1,5 +1,5 @@
 #
-# Copyright 2010-2013 Ettus Research LLC
+# Copyright 2010-2015 Ettus Research LLC
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -34,6 +34,15 @@ LIBUHD_APPEND_SOURCES(
     ${CMAKE_CURRENT_SOURCE_DIR}/subdev_spec.cpp
 )
 
+IF(ENABLE_C_API)
+    LIBUHD_APPEND_SOURCES(
+        ${CMAKE_CURRENT_SOURCE_DIR}/dboard_eeprom_c.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/mboard_eeprom_c.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/subdev_spec_c.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/usrp_c.cpp
+    )
+ENDIF(ENABLE_C_API)
+
 LIBUHD_REGISTER_COMPONENT("GPSD" ENABLE_GPSD OFF "ENABLE_LIBUHD;ENABLE_GPSD;LIBGPS_FOUND" OFF)
 
 IF(ENABLE_GPSD)
diff --git a/host/lib/usrp/dboard_eeprom_c.cpp b/host/lib/usrp/dboard_eeprom_c.cpp
new file mode 100644
index 000000000..e3ef4933f
--- /dev/null
+++ b/host/lib/usrp/dboard_eeprom_c.cpp
@@ -0,0 +1,109 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/usrp/dboard_eeprom.h>
+#include <uhd/error.h>
+
+#include <boost/lexical_cast.hpp>
+
+#include <string.h>
+
+uhd_error uhd_dboard_eeprom_make(
+    uhd_dboard_eeprom_handle* h
+){
+    UHD_SAFE_C(
+        *h = new uhd_dboard_eeprom_t;
+    )
+}
+
+uhd_error uhd_dboard_eeprom_free(
+    uhd_dboard_eeprom_handle* h
+){
+    UHD_SAFE_C(
+        delete *h;
+        *h = NULL;
+    )
+}
+
+uhd_error uhd_dboard_eeprom_get_id(
+    uhd_dboard_eeprom_handle h,
+    char* id_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string dboard_id_cpp = h->dboard_eeprom_cpp.id.to_string();
+        strncpy(id_out, dboard_id_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_dboard_eeprom_set_id(
+    uhd_dboard_eeprom_handle h,
+    const char* id
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        h->dboard_eeprom_cpp.id = uhd::usrp::dboard_id_t::from_string(id);
+    )
+}
+
+uhd_error uhd_dboard_eeprom_get_serial(
+    uhd_dboard_eeprom_handle h,
+    char* id_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string dboard_serial_cpp = h->dboard_eeprom_cpp.serial;
+        strncpy(id_out, dboard_serial_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_dboard_eeprom_set_serial(
+    uhd_dboard_eeprom_handle h,
+    const char* serial
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        h->dboard_eeprom_cpp.serial = serial;
+    )
+}
+
+uhd_error uhd_dboard_eeprom_get_revision(
+    uhd_dboard_eeprom_handle h,
+    int* revision_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *revision_out = boost::lexical_cast<int>(h->dboard_eeprom_cpp.revision);
+    )
+}
+
+uhd_error uhd_dboard_eeprom_set_revision(
+    uhd_dboard_eeprom_handle h,
+    int revision
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        h->dboard_eeprom_cpp.revision = boost::lexical_cast<std::string>(revision);
+    )
+}
+
+uhd_error uhd_dboard_eeprom_last_error(
+    uhd_dboard_eeprom_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
diff --git a/host/lib/usrp/mboard_eeprom_c.cpp b/host/lib/usrp/mboard_eeprom_c.cpp
new file mode 100644
index 000000000..8d5c069b9
--- /dev/null
+++ b/host/lib/usrp/mboard_eeprom_c.cpp
@@ -0,0 +1,72 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/usrp/mboard_eeprom.h>
+
+#include <uhd/exception.hpp>
+
+#include <string.h>
+
+uhd_error uhd_mboard_eeprom_make(
+    uhd_mboard_eeprom_handle* h
+){
+    UHD_SAFE_C(
+        *h = new uhd_mboard_eeprom_t;
+    )
+}
+
+uhd_error uhd_mboard_eeprom_free(
+    uhd_mboard_eeprom_handle* h
+){
+    UHD_SAFE_C(
+        delete *h;
+        *h = NULL;
+    )
+}
+
+uhd_error uhd_mboard_eeprom_get_value(
+    uhd_mboard_eeprom_handle h,
+    const char* key,
+    char* value_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string value_cpp = h->mboard_eeprom_cpp.get(key);
+        strncpy(value_out, value_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_mboard_eeprom_set_value(
+    uhd_mboard_eeprom_handle h,
+    const char* key,
+    const char* value
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        h->mboard_eeprom_cpp[key] = value;
+    )
+}
+
+uhd_error uhd_mboard_eeprom_last_error(
+    uhd_mboard_eeprom_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
diff --git a/host/lib/usrp/subdev_spec_c.cpp b/host/lib/usrp/subdev_spec_c.cpp
new file mode 100644
index 000000000..2c9c20506
--- /dev/null
+++ b/host/lib/usrp/subdev_spec_c.cpp
@@ -0,0 +1,149 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/usrp/subdev_spec.h>
+
+#include <string.h>
+
+uhd_error uhd_subdev_spec_pair_free(
+    uhd_subdev_spec_pair_t *subdev_spec_pair
+){
+    UHD_SAFE_C(
+        if(subdev_spec_pair->db_name){
+            free(subdev_spec_pair->db_name);
+            subdev_spec_pair->db_name = NULL;
+        }
+        if(subdev_spec_pair->sd_name){
+            free(subdev_spec_pair->sd_name);
+            subdev_spec_pair->sd_name = NULL;
+        }
+    )
+}
+
+uhd_error uhd_subdev_spec_pairs_equal(
+    const uhd_subdev_spec_pair_t* first,
+    const uhd_subdev_spec_pair_t* second,
+    bool *result_out
+){
+    UHD_SAFE_C(
+        *result_out = (uhd_subdev_spec_pair_c_to_cpp(first) ==
+                       uhd_subdev_spec_pair_c_to_cpp(second));
+    )
+}
+
+uhd_error uhd_subdev_spec_make(
+    uhd_subdev_spec_handle* h,
+    const char* markup
+){
+    UHD_SAFE_C(
+        (*h) = new uhd_subdev_spec_t;
+        std::string markup_cpp(markup);
+        if(!markup_cpp.empty()){
+            (*h)->subdev_spec_cpp = uhd::usrp::subdev_spec_t(markup_cpp);
+        }
+    )
+}
+
+uhd_error uhd_subdev_spec_free(
+    uhd_subdev_spec_handle* h
+){
+    UHD_SAFE_C(
+        delete (*h);
+        (*h) = NULL;
+    )
+}
+
+uhd_error uhd_subdev_spec_size(
+    uhd_subdev_spec_handle h,
+    size_t *size_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *size_out = h->subdev_spec_cpp.size();
+    )
+}
+
+uhd_error uhd_subdev_spec_push_back(
+    uhd_subdev_spec_handle h,
+    const char* markup
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        h->subdev_spec_cpp.push_back(uhd::usrp::subdev_spec_pair_t(markup));
+    )
+}
+
+uhd_error uhd_subdev_spec_at(
+    uhd_subdev_spec_handle h,
+    size_t num,
+    uhd_subdev_spec_pair_t *subdev_spec_pair_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd_subdev_spec_pair_cpp_to_c(
+            h->subdev_spec_cpp.at(num),
+            subdev_spec_pair_out
+        );
+    )
+}
+
+uhd_error uhd_subdev_spec_to_pp_string(
+    uhd_subdev_spec_handle h,
+    char* pp_string_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string pp_string_cpp = h->subdev_spec_cpp.to_pp_string();
+        memset(pp_string_out, '\0', strbuffer_len);
+        strncpy(pp_string_out, pp_string_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_subdev_spec_to_string(
+    uhd_subdev_spec_handle h,
+    char* string_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string string_cpp = h->subdev_spec_cpp.to_string();
+        memset(string_out, '\0', strbuffer_len);
+        strncpy(string_out, string_cpp.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_subdev_spec_last_error(
+    uhd_subdev_spec_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
+
+uhd::usrp::subdev_spec_pair_t uhd_subdev_spec_pair_c_to_cpp(
+    const uhd_subdev_spec_pair_t *subdev_spec_pair_c
+){
+    return uhd::usrp::subdev_spec_pair_t(subdev_spec_pair_c->db_name,
+                                         subdev_spec_pair_c->sd_name);
+}
+
+void uhd_subdev_spec_pair_cpp_to_c(
+    const uhd::usrp::subdev_spec_pair_t &subdev_spec_pair_cpp,
+    uhd_subdev_spec_pair_t *subdev_spec_pair_c
+){
+    subdev_spec_pair_c->db_name = strdup(subdev_spec_pair_cpp.db_name.c_str());
+    subdev_spec_pair_c->sd_name = strdup(subdev_spec_pair_cpp.sd_name.c_str());
+}
diff --git a/host/lib/usrp/usrp_c.cpp b/host/lib/usrp/usrp_c.cpp
new file mode 100644
index 000000000..3eaf70405
--- /dev/null
+++ b/host/lib/usrp/usrp_c.cpp
@@ -0,0 +1,1509 @@
+/*
+ * Copyright 2015 Ettus Research LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* C-Interface for multi_usrp */
+
+#include <uhd/utils/static.hpp>
+#include <uhd/usrp/multi_usrp.hpp>
+
+#include <uhd/error.h>
+#include <uhd/usrp/usrp.h>
+
+#include <boost/foreach.hpp>
+#include <boost/thread/mutex.hpp>
+
+#include <string.h>
+#include <map>
+
+/****************************************************************************
+ * Helpers
+ ***************************************************************************/
+uhd::stream_args_t stream_args_c_to_cpp(const uhd_stream_args_t *stream_args_c)
+{
+    std::string otw_format(stream_args_c->otw_format);
+    std::string cpu_format(stream_args_c->cpu_format);
+    std::string args(stream_args_c->args);
+    std::vector<size_t> channels(stream_args_c->channel_list, stream_args_c->channel_list + stream_args_c->n_channels);
+
+    uhd::stream_args_t stream_args_cpp(cpu_format, otw_format);
+    stream_args_cpp.args = args;
+    stream_args_cpp.channels = channels;
+
+    return stream_args_cpp;
+}
+
+uhd::stream_cmd_t stream_cmd_c_to_cpp(const uhd_stream_cmd_t *stream_cmd_c)
+{
+    uhd::stream_cmd_t stream_cmd_cpp(uhd::stream_cmd_t::stream_mode_t(stream_cmd_c->stream_mode));
+    stream_cmd_cpp.num_samps   = stream_cmd_c->num_samps;
+    stream_cmd_cpp.stream_now  = stream_cmd_c->stream_now;
+    stream_cmd_cpp.time_spec   = uhd::time_spec_t(stream_cmd_c->time_spec_full_secs, stream_cmd_c->time_spec_frac_secs);
+    return stream_cmd_cpp;
+}
+
+/****************************************************************************
+ * Registry / Pointer Management
+ ***************************************************************************/
+/* Public structs */
+struct uhd_usrp {
+    size_t usrp_index;
+    std::string last_error;
+};
+
+struct uhd_tx_streamer {
+    size_t usrp_index;
+    size_t streamer_index;
+    std::string last_error;
+};
+
+struct uhd_rx_streamer {
+    size_t usrp_index;
+    size_t streamer_index;
+    std::string last_error;
+};
+
+/* Not public: We use this for our internal registry */
+struct usrp_ptr {
+    uhd::usrp::multi_usrp::sptr ptr;
+    std::vector< uhd::rx_streamer::sptr > rx_streamers;
+    std::vector< uhd::tx_streamer::sptr > tx_streamers;
+    static size_t usrp_counter;
+};
+size_t usrp_ptr::usrp_counter = 0;
+typedef struct usrp_ptr usrp_ptr;
+/* Prefer map, because the list can be discontiguous */
+typedef std::map<size_t, usrp_ptr> usrp_ptrs;
+
+UHD_SINGLETON_FCN(usrp_ptrs, get_usrp_ptrs);
+/* Shortcut for accessing the underlying USRP sptr from a uhd_usrp_handle* */
+#define USRP(h_ptr) (get_usrp_ptrs()[h_ptr->usrp_index].ptr)
+#define RX_STREAMER(h_ptr) (get_usrp_ptrs()[h_ptr->usrp_index].rx_streamers[h_ptr->streamer_index])
+#define TX_STREAMER(h_ptr) (get_usrp_ptrs()[h_ptr->usrp_index].tx_streamers[h_ptr->streamer_index])
+
+/****************************************************************************
+ * RX Streamer
+ ***************************************************************************/
+static boost::mutex _rx_streamer_make_mutex;
+uhd_error uhd_rx_streamer_make(uhd_rx_streamer_handle* h){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock(_rx_streamer_make_mutex);
+        (*h) = new uhd_rx_streamer;
+    )
+}
+
+static boost::mutex _rx_streamer_free_mutex;
+uhd_error uhd_rx_streamer_free(uhd_rx_streamer_handle* h){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_rx_streamer_free_mutex);
+        delete (*h);
+        (*h) = NULL;
+    )
+}
+
+uhd_error uhd_rx_streamer_num_channels(uhd_rx_streamer_handle h,
+                                       size_t *num_channels_out){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *num_channels_out = RX_STREAMER(h)->get_num_channels();
+    )
+}
+
+uhd_error uhd_rx_streamer_max_num_samps(uhd_rx_streamer_handle h,
+                                        size_t *max_num_samps_out){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *max_num_samps_out = RX_STREAMER(h)->get_max_num_samps();
+    )
+}
+
+uhd_error uhd_rx_streamer_recv(
+    uhd_rx_streamer_handle h,
+    void **buffs,
+    size_t samps_per_buff,
+    uhd_rx_metadata_handle md,
+    double timeout,
+    bool one_packet,
+    size_t *items_recvd
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::rx_streamer::buffs_type buffs_cpp(buffs, RX_STREAMER(h)->get_num_channels());
+        *items_recvd = RX_STREAMER(h)->recv(buffs_cpp, samps_per_buff, md->rx_metadata_cpp, timeout, one_packet);
+    )
+}
+
+uhd_error uhd_rx_streamer_issue_stream_cmd(
+    uhd_rx_streamer_handle h,
+    const uhd_stream_cmd_t *stream_cmd
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        RX_STREAMER(h)->issue_stream_cmd(stream_cmd_c_to_cpp(stream_cmd));
+    )
+}
+
+uhd_error uhd_rx_streamer_last_error(
+    uhd_rx_streamer_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
+
+/****************************************************************************
+ * TX Streamer
+ ***************************************************************************/
+static boost::mutex _tx_streamer_make_mutex;
+uhd_error uhd_tx_streamer_make(
+    uhd_tx_streamer_handle* h
+){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_tx_streamer_make_mutex);
+        (*h) = new uhd_tx_streamer;
+    )
+}
+
+static boost::mutex _tx_streamer_free_mutex;
+uhd_error uhd_tx_streamer_free(
+    uhd_tx_streamer_handle* h
+){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_tx_streamer_free_mutex);
+        delete *h;
+        *h = NULL;
+    )
+}
+
+uhd_error uhd_tx_streamer_num_channels(
+    uhd_tx_streamer_handle h,
+    size_t *num_channels_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *num_channels_out = TX_STREAMER(h)->get_num_channels();
+    )
+}
+
+uhd_error uhd_tx_streamer_max_num_samps(
+    uhd_tx_streamer_handle h,
+    size_t *max_num_samps_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *max_num_samps_out = TX_STREAMER(h)->get_max_num_samps();
+    )
+}
+
+uhd_error uhd_tx_streamer_send(
+    uhd_tx_streamer_handle h,
+    const void **buffs,
+    const size_t samps_per_buff,
+    const uhd_tx_metadata_handle md,
+    const double timeout,
+    size_t *items_sent
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::tx_streamer::buffs_type buffs_cpp(buffs, TX_STREAMER(h)->get_num_channels());
+        *items_sent = TX_STREAMER(h)->send(
+            buffs_cpp,
+            samps_per_buff,
+            md->tx_metadata_cpp,
+            timeout
+        );
+    )
+}
+
+uhd_error uhd_tx_streamer_recv_async_msg(
+    uhd_tx_streamer_handle h,
+    uhd_async_metadata_handle md,
+    const double timeout,
+    bool *valid
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *valid = TX_STREAMER(h)->recv_async_msg(md->async_metadata_cpp, timeout);
+    )
+}
+
+uhd_error uhd_tx_streamer_last_error(
+    uhd_tx_streamer_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
+
+/****************************************************************************
+ * Generate / Destroy API calls
+ ***************************************************************************/
+static boost::mutex _usrp_make_mutex;
+uhd_error uhd_usrp_make(
+    uhd_usrp_handle *h,
+    const char *args
+){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_usrp_make_mutex);
+
+        size_t usrp_count = usrp_ptr::usrp_counter;
+        usrp_ptr::usrp_counter++;
+
+        // Initialize USRP
+        uhd::device_addr_t device_addr(args);
+        usrp_ptr P;
+        P.ptr = uhd::usrp::multi_usrp::make(device_addr);
+
+        // Dump into registry
+        get_usrp_ptrs()[usrp_count] = P;
+
+        // Update handle
+        (*h) = new uhd_usrp;
+        (*h)->usrp_index = usrp_count;
+    )
+}
+
+static boost::mutex _usrp_free_mutex;
+uhd_error uhd_usrp_free(
+    uhd_usrp_handle *h
+){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_usrp_free_mutex);
+
+        if(!get_usrp_ptrs().count((*h)->usrp_index)){
+            return UHD_ERROR_INVALID_DEVICE;
+        }
+
+        get_usrp_ptrs().erase((*h)->usrp_index);
+        delete *h;
+        *h = NULL;
+    )
+}
+
+uhd_error uhd_usrp_last_error(
+    uhd_usrp_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
+
+static boost::mutex _usrp_get_rx_stream_mutex;
+uhd_error uhd_usrp_get_rx_stream(
+    uhd_usrp_handle h_u,
+    uhd_stream_args_t *stream_args,
+    uhd_rx_streamer_handle h_s
+){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_usrp_get_rx_stream_mutex);
+
+        if(!get_usrp_ptrs().count(h_u->usrp_index)){
+            return UHD_ERROR_INVALID_DEVICE;
+        }
+
+        usrp_ptr &usrp = get_usrp_ptrs()[h_u->usrp_index];
+        usrp.rx_streamers.push_back(
+            usrp.ptr->get_rx_stream(stream_args_c_to_cpp(stream_args))
+        );
+        h_s->usrp_index     = h_u->usrp_index;
+        h_s->streamer_index = usrp.rx_streamers.size() - 1;
+    )
+}
+
+static boost::mutex _usrp_get_tx_stream_mutex;
+uhd_error uhd_usrp_get_tx_stream(
+    uhd_usrp_handle h_u,
+    uhd_stream_args_t *stream_args,
+    uhd_tx_streamer_handle h_s
+){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_usrp_get_tx_stream_mutex);
+
+        if(!get_usrp_ptrs().count(h_u->usrp_index)){
+            return UHD_ERROR_INVALID_DEVICE;
+        }
+
+        usrp_ptr &usrp = get_usrp_ptrs()[h_u->usrp_index];
+        usrp.tx_streamers.push_back(
+            usrp.ptr->get_tx_stream(stream_args_c_to_cpp(stream_args))
+        );
+        h_s->usrp_index     = h_u->usrp_index;
+        h_s->streamer_index = usrp.tx_streamers.size() - 1;
+    )
+}
+
+/****************************************************************************
+ * multi_usrp API calls
+ ***************************************************************************/
+
+#define COPY_INFO_FIELD(out, dict, field) \
+    out->field = strdup(dict.get(BOOST_STRINGIZE(field)).c_str())
+
+uhd_error uhd_usrp_get_rx_info(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_usrp_rx_info_t *info_out
+) {
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::dict<std::string, std::string> rx_info = USRP(h)->get_usrp_rx_info(chan);
+
+        COPY_INFO_FIELD(info_out, rx_info, mboard_id);
+        COPY_INFO_FIELD(info_out, rx_info, mboard_serial);
+        COPY_INFO_FIELD(info_out, rx_info, rx_id);
+        COPY_INFO_FIELD(info_out, rx_info, rx_subdev_name);
+        COPY_INFO_FIELD(info_out, rx_info, rx_subdev_spec);
+        COPY_INFO_FIELD(info_out, rx_info, rx_serial);
+        COPY_INFO_FIELD(info_out, rx_info, rx_antenna);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_info(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_usrp_tx_info_t *info_out
+) {
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::dict<std::string, std::string> tx_info = USRP(h)->get_usrp_tx_info(chan);
+
+        COPY_INFO_FIELD(info_out, tx_info, mboard_id);
+        COPY_INFO_FIELD(info_out, tx_info, mboard_serial);
+        COPY_INFO_FIELD(info_out, tx_info, tx_id);
+        COPY_INFO_FIELD(info_out, tx_info, tx_subdev_name);
+        COPY_INFO_FIELD(info_out, tx_info, tx_subdev_spec);
+        COPY_INFO_FIELD(info_out, tx_info, tx_serial);
+        COPY_INFO_FIELD(info_out, tx_info, tx_antenna);
+    )
+}
+
+/****************************************************************************
+ * Motherboard methods
+ ***************************************************************************/
+uhd_error uhd_usrp_set_master_clock_rate(
+    uhd_usrp_handle h,
+    double rate,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_master_clock_rate(rate, mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_master_clock_rate(
+    uhd_usrp_handle h,
+    size_t mboard,
+    double *clock_rate_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *clock_rate_out = USRP(h)->get_master_clock_rate(mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_pp_string(
+    uhd_usrp_handle h,
+    char* pp_string_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        strncpy(pp_string_out, USRP(h)->get_pp_string().c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_get_mboard_name(
+    uhd_usrp_handle h,
+    size_t mboard,
+    char* mboard_name_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        strncpy(mboard_name_out, USRP(h)->get_mboard_name(mboard).c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_get_time_now(
+    uhd_usrp_handle h,
+    size_t mboard,
+    time_t *full_secs_out,
+    double *frac_secs_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp = USRP(h)->get_time_now(mboard);
+        *full_secs_out = time_spec_cpp.get_full_secs();
+        *frac_secs_out = time_spec_cpp.get_frac_secs();
+    )
+}
+
+uhd_error uhd_usrp_get_time_last_pps(
+    uhd_usrp_handle h,
+    size_t mboard,
+    time_t *full_secs_out,
+    double *frac_secs_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp = USRP(h)->get_time_last_pps(mboard);
+        *full_secs_out = time_spec_cpp.get_full_secs();
+        *frac_secs_out = time_spec_cpp.get_frac_secs();
+    )
+}
+
+uhd_error uhd_usrp_set_time_now(
+    uhd_usrp_handle h,
+    time_t full_secs,
+    double frac_secs,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp(full_secs, frac_secs);
+        USRP(h)->set_time_now(time_spec_cpp, mboard);
+    )
+}
+
+uhd_error uhd_usrp_set_time_next_pps(
+    uhd_usrp_handle h,
+    time_t full_secs,
+    double frac_secs,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp(full_secs, frac_secs);
+        USRP(h)->set_time_next_pps(time_spec_cpp, mboard);
+    )
+}
+
+uhd_error uhd_usrp_set_time_unknown_pps(
+    uhd_usrp_handle h,
+    time_t full_secs,
+    double frac_secs
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp(full_secs, frac_secs);
+        USRP(h)->set_time_unknown_pps(time_spec_cpp);
+    )
+}
+
+uhd_error uhd_usrp_get_time_synchronized(
+    uhd_usrp_handle h,
+    bool *result_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *result_out = USRP(h)->get_time_synchronized();
+        return UHD_ERROR_NONE;
+    )
+}
+
+uhd_error uhd_usrp_set_command_time(
+    uhd_usrp_handle h,
+    time_t full_secs,
+    double frac_secs,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::time_spec_t time_spec_cpp(full_secs, frac_secs);
+        USRP(h)->set_command_time(time_spec_cpp, mboard);
+    )
+}
+
+uhd_error uhd_usrp_clear_command_time(
+    uhd_usrp_handle h,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->clear_command_time(mboard);
+    )
+}
+
+uhd_error uhd_usrp_issue_stream_cmd(
+    uhd_usrp_handle h,
+    uhd_stream_cmd_t *stream_cmd,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->issue_stream_cmd(stream_cmd_c_to_cpp(stream_cmd), chan);
+    )
+}
+
+uhd_error uhd_usrp_set_time_source(
+    uhd_usrp_handle h,
+    const char* time_source,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_time_source(std::string(time_source), mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_time_source(
+    uhd_usrp_handle h,
+    size_t mboard,
+    char* time_source_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        strncpy(time_source_out, USRP(h)->get_time_source(mboard).c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_get_time_sources(
+    uhd_usrp_handle h,
+    size_t mboard,
+    char* time_sources_out,
+    size_t strbuffer_len,
+    size_t *num_time_sources_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> time_sources = USRP(h)->get_time_sources(mboard);
+        *num_time_sources_out = time_sources.size();
+
+        std::string time_sources_str = "";
+        BOOST_FOREACH(const std::string &time_source, time_sources){
+            time_sources_str += time_source;
+            time_sources_str += ',';
+        }
+        if(time_sources.size() > 0){
+            time_sources_str.resize(time_sources_str.size()-1);
+        }
+
+        memset(time_sources_out, '\0', strbuffer_len);
+        strncpy(time_sources_out, time_sources_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_clock_source(
+    uhd_usrp_handle h,
+    const char* clock_source,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_clock_source(std::string(clock_source), mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_clock_source(
+    uhd_usrp_handle h,
+    size_t mboard,
+    char* clock_source_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        strncpy(clock_source_out, USRP(h)->get_clock_source(mboard).c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_get_clock_sources(
+    uhd_usrp_handle h,
+    size_t mboard,
+    char* clock_sources_out,
+    size_t strbuffer_len,
+    size_t *num_clock_sources_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> clock_sources = USRP(h)->get_clock_sources(mboard);
+        *num_clock_sources_out = clock_sources.size();
+
+        std::string clock_sources_str = "";
+        BOOST_FOREACH(const std::string &clock_source, clock_sources){
+            clock_sources_str += clock_source;
+            clock_sources_str += ',';
+        }
+        if(clock_sources.size() > 0){
+            clock_sources_str.resize(clock_sources_str.size()-1);
+        }
+
+        memset(clock_sources_out, '\0', strbuffer_len);
+        strncpy(clock_sources_out, clock_sources_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_clock_source_out(
+    uhd_usrp_handle h,
+    bool enb,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_clock_source_out(enb, mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_num_mboards(
+    uhd_usrp_handle h,
+    size_t *num_mboards_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *num_mboards_out = USRP(h)->get_num_mboards();
+    )
+}
+
+uhd_error uhd_usrp_get_mboard_sensor(
+    uhd_usrp_handle h,
+    const char* name,
+    size_t mboard,
+    uhd_sensor_value_handle sensor_value_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        delete sensor_value_out->sensor_value_cpp;
+        sensor_value_out->sensor_value_cpp = new uhd::sensor_value_t(USRP(h)->get_mboard_sensor(name, mboard));
+    )
+}
+
+uhd_error uhd_usrp_get_mboard_sensor_names(
+    uhd_usrp_handle h,
+    size_t mboard,
+    char* mboard_sensor_names_out,
+    size_t strbuffer_len,
+    size_t *num_mboard_sensors_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> mboard_sensor_names = USRP(h)->get_mboard_sensor_names(mboard);
+        *num_mboard_sensors_out = mboard_sensor_names.size();
+
+        std::string mboard_sensor_names_str = "";
+        BOOST_FOREACH(const std::string &mboard_sensor_name, mboard_sensor_names){
+            mboard_sensor_names_str += mboard_sensor_name;
+            mboard_sensor_names_str += ',';
+        }
+        if(mboard_sensor_names.size() > 0){
+            mboard_sensor_names_str.resize(mboard_sensor_names_str.size()-1);
+        }
+
+        memset(mboard_sensor_names_out, '\0', strbuffer_len);
+        strncpy(mboard_sensor_names_out, mboard_sensor_names_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_user_register(
+    uhd_usrp_handle h,
+    uint8_t addr,
+    uint32_t data,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_user_register(addr, data, mboard);
+    )
+}
+
+/****************************************************************************
+ * EEPROM access methods
+ ***************************************************************************/
+
+uhd_error uhd_usrp_get_mboard_eeprom(
+    uhd_usrp_handle h,
+    uhd_mboard_eeprom_handle mb_eeprom,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::fs_path eeprom_path = str(boost::format("/mboards/%d/eeprom")
+                                       % mboard);
+
+        uhd::property_tree::sptr ptree = USRP(h)->get_device()->get_tree();
+        mb_eeprom->mboard_eeprom_cpp = ptree->access<uhd::usrp::mboard_eeprom_t>(eeprom_path).get();
+    )
+}
+
+uhd_error uhd_usrp_set_mboard_eeprom(
+    uhd_usrp_handle h,
+    uhd_mboard_eeprom_handle mb_eeprom,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::fs_path eeprom_path = str(boost::format("/mboards/%d/eeprom")
+                                       % mboard);
+
+        uhd::property_tree::sptr ptree = USRP(h)->get_device()->get_tree();
+        ptree->access<uhd::usrp::mboard_eeprom_t>(eeprom_path).set(mb_eeprom->mboard_eeprom_cpp);
+    )
+}
+
+uhd_error uhd_usrp_get_dboard_eeprom(
+    uhd_usrp_handle h,
+    uhd_dboard_eeprom_handle db_eeprom,
+    const char* unit,
+    const char* slot,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::fs_path eeprom_path = str(boost::format("/mboards/%d/dboards/%s/%s_eeprom")
+                                       % mboard % slot % unit);
+
+        uhd::property_tree::sptr ptree = USRP(h)->get_device()->get_tree();
+        db_eeprom->dboard_eeprom_cpp = ptree->access<uhd::usrp::dboard_eeprom_t>(eeprom_path).get();
+    )
+}
+
+uhd_error uhd_usrp_set_dboard_eeprom(
+    uhd_usrp_handle h,
+    uhd_dboard_eeprom_handle db_eeprom,
+    const char* unit,
+    const char* slot,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::fs_path eeprom_path = str(boost::format("/mboards/%d/dboards/%s/%s_eeprom")
+                                       % mboard % slot % unit);
+
+        uhd::property_tree::sptr ptree = USRP(h)->get_device()->get_tree();
+        ptree->access<uhd::usrp::dboard_eeprom_t>(eeprom_path).set(db_eeprom->dboard_eeprom_cpp);
+    )
+}
+
+/****************************************************************************
+ * RX methods
+ ***************************************************************************/
+
+uhd_error uhd_usrp_set_rx_subdev_spec(
+    uhd_usrp_handle h,
+    uhd_subdev_spec_handle subdev_spec,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_rx_subdev_spec(subdev_spec->subdev_spec_cpp, mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_subdev_spec(
+    uhd_usrp_handle h,
+    size_t mboard,
+    uhd_subdev_spec_handle subdev_spec_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        subdev_spec_out->subdev_spec_cpp = USRP(h)->get_rx_subdev_spec(mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_num_channels(
+    uhd_usrp_handle h,
+    size_t *num_channels_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *num_channels_out = USRP(h)->get_rx_num_channels();
+    )
+}
+
+uhd_error uhd_usrp_get_rx_subdev_name(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* rx_subdev_name_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string rx_subdev_name = USRP(h)->get_rx_subdev_name(chan);
+        strncpy(rx_subdev_name_out, rx_subdev_name.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_rx_rate(
+    uhd_usrp_handle h,
+    double rate,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_rx_rate(rate, chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_rate(
+    uhd_usrp_handle h,
+    size_t chan,
+    double *rate_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *rate_out = USRP(h)->get_rx_rate(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_rates(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_meta_range_handle rates_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        rates_out->meta_range_cpp = USRP(h)->get_rx_rates(chan);
+    )
+}
+
+uhd_error uhd_usrp_set_rx_freq(
+    uhd_usrp_handle h,
+    uhd_tune_request_t *tune_request,
+    size_t chan,
+    uhd_tune_result_t *tune_result
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::tune_request_t tune_request_cpp = uhd_tune_request_c_to_cpp(tune_request);
+        uhd::tune_result_t tune_result_cpp = USRP(h)->set_rx_freq(tune_request_cpp, chan);
+        uhd_tune_result_cpp_to_c(tune_result_cpp, tune_result);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_freq(
+    uhd_usrp_handle h,
+    size_t chan,
+    double *freq_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *freq_out = USRP(h)->get_rx_freq(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_freq_range(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_meta_range_handle freq_range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        freq_range_out->meta_range_cpp = USRP(h)->get_rx_freq_range(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_fe_rx_freq_range(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_meta_range_handle freq_range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        freq_range_out->meta_range_cpp = USRP(h)->get_fe_rx_freq_range(chan);
+    )
+}
+
+uhd_error uhd_usrp_set_rx_gain(
+    uhd_usrp_handle h,
+    double gain,
+    size_t chan,
+    const char *gain_name
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string name(gain_name);
+        if(name.empty()){
+            USRP(h)->set_rx_gain(gain, chan);
+        }
+        else{
+            USRP(h)->set_rx_gain(gain, name, chan);
+        }
+    )
+}
+
+uhd_error uhd_usrp_set_normalized_rx_gain(
+    uhd_usrp_handle h,
+    double gain,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_normalized_rx_gain(gain, chan);
+    )
+}
+
+uhd_error uhd_usrp_set_rx_agc(
+    uhd_usrp_handle h,
+    bool enable,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_rx_agc(enable, chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_gain(
+    uhd_usrp_handle h,
+    size_t chan,
+    const char *gain_name,
+    double *gain_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string name(gain_name);
+        if(name.empty()){
+            *gain_out = USRP(h)->get_rx_gain(chan);
+        }
+        else{
+            *gain_out = USRP(h)->get_rx_gain(name, chan);
+        }
+    )
+}
+
+uhd_error uhd_usrp_get_normalized_rx_gain(
+    uhd_usrp_handle h,
+    size_t chan,
+    double *gain_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *gain_out = USRP(h)->get_normalized_rx_gain(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_gain_range(
+    uhd_usrp_handle h,
+    const char* name,
+    size_t chan,
+    uhd_meta_range_handle gain_range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        gain_range_out->meta_range_cpp = USRP(h)->get_rx_gain_range(name, chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_gain_names(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* gain_names_out,
+    size_t strbuffer_len,
+    size_t *num_rx_gain_names_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> rx_gain_names = USRP(h)->get_rx_gain_names(chan);
+        *num_rx_gain_names_out = rx_gain_names.size();
+
+        std::string rx_gain_names_str = "";
+        BOOST_FOREACH(const std::string &gain_name, rx_gain_names){
+            rx_gain_names_str += gain_name;
+            rx_gain_names_str += ',';
+        }
+        if(rx_gain_names.size() > 0){
+            rx_gain_names_str.resize(rx_gain_names_str.size()-1);
+        }
+
+        memset(gain_names_out, '\0', strbuffer_len);
+        strncpy(gain_names_out, rx_gain_names_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_rx_antenna(
+    uhd_usrp_handle h,
+    const char* ant,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_rx_antenna(std::string(ant), chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_antenna(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* ant_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string rx_antenna = USRP(h)->get_rx_antenna(chan);
+        strncpy(ant_out, rx_antenna.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_antennas(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* antennas_out,
+    size_t strbuffer_len,
+    size_t *num_rx_antennas_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> rx_antennas = USRP(h)->get_rx_antennas(chan);
+        *num_rx_antennas_out = rx_antennas.size();
+
+        std::string rx_antennas_str = "";
+        BOOST_FOREACH(const std::string &rx_antenna, rx_antennas){
+            rx_antennas_str += rx_antenna;
+            rx_antennas_str += ',';
+        }
+        if(rx_antennas.size() > 0){
+            rx_antennas_str.resize(rx_antennas_str.size()-1);
+        }
+
+        memset(antennas_out, '\0', strbuffer_len);
+        strncpy(antennas_out, rx_antennas_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_rx_bandwidth(
+    uhd_usrp_handle h,
+    double bandwidth,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_rx_bandwidth(bandwidth, chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_bandwidth(
+    uhd_usrp_handle h,
+    size_t chan,
+    double *bandwidth_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *bandwidth_out = USRP(h)->get_rx_bandwidth(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_bandwidth_range(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_meta_range_handle bandwidth_range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        bandwidth_range_out->meta_range_cpp = USRP(h)->get_rx_bandwidth_range(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_rx_sensor(
+    uhd_usrp_handle h,
+    const char* name,
+    size_t chan,
+    uhd_sensor_value_handle sensor_value_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        delete sensor_value_out->sensor_value_cpp;
+        sensor_value_out->sensor_value_cpp = new uhd::sensor_value_t(USRP(h)->get_rx_sensor(name, chan));
+    )
+}
+
+uhd_error uhd_usrp_get_rx_sensor_names(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* sensor_names_out,
+    size_t strbuffer_len,
+    size_t *num_rx_sensors_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> rx_sensor_names = USRP(h)->get_rx_sensor_names(chan);
+        *num_rx_sensors_out = rx_sensor_names.size();
+
+        std::string rx_sensor_names_str = "";
+        BOOST_FOREACH(const std::string &rx_sensor_name, rx_sensor_names){
+            rx_sensor_names_str += rx_sensor_name;
+            rx_sensor_names_str += ',';
+        }
+        if(rx_sensor_names.size() > 0){
+            rx_sensor_names_str.resize(rx_sensor_names_str.size()-1);
+        }
+
+        memset(sensor_names_out, '\0', strbuffer_len);
+        strncpy(sensor_names_out, rx_sensor_names_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_rx_dc_offset_enabled(
+    uhd_usrp_handle h,
+    bool enb,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_rx_dc_offset(enb, chan);
+    )
+}
+
+uhd_error uhd_usrp_set_rx_iq_balance_enabled(
+    uhd_usrp_handle h,
+    bool enb,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_rx_iq_balance(enb, chan);
+    )
+}
+
+/****************************************************************************
+ * TX methods
+ ***************************************************************************/
+
+uhd_error uhd_usrp_set_tx_subdev_spec(
+    uhd_usrp_handle h,
+    uhd_subdev_spec_handle subdev_spec,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_tx_subdev_spec(subdev_spec->subdev_spec_cpp, mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_subdev_spec(
+    uhd_usrp_handle h,
+    size_t mboard,
+    uhd_subdev_spec_handle subdev_spec_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        subdev_spec_out->subdev_spec_cpp = USRP(h)->get_tx_subdev_spec(mboard);
+    )
+}
+
+
+uhd_error uhd_usrp_get_tx_num_channels(
+    uhd_usrp_handle h,
+    size_t *num_channels_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *num_channels_out = USRP(h)->get_tx_num_channels();
+    )
+}
+
+uhd_error uhd_usrp_get_tx_subdev_name(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* tx_subdev_name_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string tx_subdev_name = USRP(h)->get_tx_subdev_name(chan);
+        strncpy(tx_subdev_name_out, tx_subdev_name.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_tx_rate(
+    uhd_usrp_handle h,
+    double rate,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_tx_rate(rate, chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_rate(
+    uhd_usrp_handle h,
+    size_t chan,
+    double *rate_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *rate_out = USRP(h)->get_tx_rate(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_rates(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_meta_range_handle rates_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        rates_out->meta_range_cpp = USRP(h)->get_tx_rates(chan);
+    )
+}
+
+uhd_error uhd_usrp_set_tx_freq(
+    uhd_usrp_handle h,
+    uhd_tune_request_t *tune_request,
+    size_t chan,
+    uhd_tune_result_t *tune_result
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        uhd::tune_request_t tune_request_cpp = uhd_tune_request_c_to_cpp(tune_request);
+        uhd::tune_result_t tune_result_cpp = USRP(h)->set_tx_freq(tune_request_cpp, chan);
+        uhd_tune_result_cpp_to_c(tune_result_cpp, tune_result);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_freq(
+    uhd_usrp_handle h,
+    size_t chan,
+    double *freq_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *freq_out = USRP(h)->get_tx_freq(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_freq_range(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_meta_range_handle freq_range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        freq_range_out->meta_range_cpp = USRP(h)->get_tx_freq_range(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_fe_tx_freq_range(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_meta_range_handle freq_range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        freq_range_out->meta_range_cpp = USRP(h)->get_fe_tx_freq_range(chan);
+    )
+}
+
+uhd_error uhd_usrp_set_tx_gain(
+    uhd_usrp_handle h,
+    double gain,
+    size_t chan,
+    const char *gain_name
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string name(gain_name);
+        if(name.empty()){
+            USRP(h)->set_tx_gain(gain, chan);
+        }
+        else{
+            USRP(h)->set_tx_gain(gain, name, chan);
+        }
+    )
+}
+
+uhd_error uhd_usrp_set_normalized_tx_gain(
+    uhd_usrp_handle h,
+    double gain,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_normalized_tx_gain(gain, chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_gain(
+    uhd_usrp_handle h,
+    size_t chan,
+    const char *gain_name,
+    double *gain_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string name(gain_name);
+        if(name.empty()){
+            *gain_out = USRP(h)->get_tx_gain(chan);
+        }
+        else{
+            *gain_out = USRP(h)->get_tx_gain(name, chan);
+        }
+    )
+}
+
+uhd_error uhd_usrp_get_normalized_tx_gain(
+    uhd_usrp_handle h,
+    size_t chan,
+    double *gain_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *gain_out = USRP(h)->get_normalized_tx_gain(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_gain_range(
+    uhd_usrp_handle h,
+    const char* name,
+    size_t chan,
+    uhd_meta_range_handle gain_range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        gain_range_out->meta_range_cpp = USRP(h)->get_tx_gain_range(name, chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_gain_names(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* gain_names_out,
+    size_t strbuffer_len,
+    size_t *num_tx_gain_names_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> tx_gain_names = USRP(h)->get_tx_gain_names(chan);
+        *num_tx_gain_names_out = tx_gain_names.size();
+
+        std::string tx_gain_names_str = "";
+        BOOST_FOREACH(const std::string &tx_gain_name, tx_gain_names){
+            tx_gain_names_str += tx_gain_name;
+            tx_gain_names_str += ',';
+        }
+        if(tx_gain_names.size() > 0){
+            tx_gain_names_str.resize(tx_gain_names_str.size()-1);
+        }
+
+        memset(gain_names_out, '\0', strbuffer_len);
+        strncpy(gain_names_out, tx_gain_names_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_tx_antenna(
+    uhd_usrp_handle h,
+    const char* ant,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_tx_antenna(std::string(ant), chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_antenna(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* ant_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::string tx_antenna = USRP(h)->get_tx_antenna(chan);
+        strncpy(ant_out, tx_antenna.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_antennas(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* antennas_out,
+    size_t strbuffer_len,
+    size_t *num_tx_antennas_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> tx_antennas = USRP(h)->get_tx_antennas(chan);
+        *num_tx_antennas_out = tx_antennas.size();
+
+        std::string tx_antennas_str = "";
+        BOOST_FOREACH(const std::string &tx_antenna, tx_antennas){
+            tx_antennas_str += tx_antenna;
+            tx_antennas_str += ',';
+        }
+        if(tx_antennas.size() > 0){
+            tx_antennas_str.resize(tx_antennas_str.size()-1);
+        }
+
+        memset(antennas_out, '\0', strbuffer_len);
+        strncpy(antennas_out, tx_antennas_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_tx_bandwidth(
+    uhd_usrp_handle h,
+    double bandwidth,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_tx_bandwidth(bandwidth, chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_bandwidth(
+    uhd_usrp_handle h,
+    size_t chan,
+    double *bandwidth_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *bandwidth_out = USRP(h)->get_tx_bandwidth(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_bandwidth_range(
+    uhd_usrp_handle h,
+    size_t chan,
+    uhd_meta_range_handle bandwidth_range_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        bandwidth_range_out->meta_range_cpp = USRP(h)->get_tx_bandwidth_range(chan);
+    )
+}
+
+uhd_error uhd_usrp_get_tx_sensor(
+    uhd_usrp_handle h,
+    const char* name,
+    size_t chan,
+    uhd_sensor_value_handle sensor_value_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        delete sensor_value_out->sensor_value_cpp;
+        sensor_value_out->sensor_value_cpp = new uhd::sensor_value_t(USRP(h)->get_tx_sensor(name, chan));
+    )
+}
+
+uhd_error uhd_usrp_get_tx_sensor_names(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* sensor_names_out,
+    size_t strbuffer_len,
+    size_t *num_tx_sensors_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> tx_sensor_names = USRP(h)->get_tx_sensor_names(chan);
+        *num_tx_sensors_out = tx_sensor_names.size();
+
+        std::string tx_sensor_names_str = "";
+        BOOST_FOREACH(const std::string &tx_sensor_name, tx_sensor_names){
+            tx_sensor_names_str += tx_sensor_name;
+            tx_sensor_names_str += ',';
+        }
+        if(tx_sensor_names.size() > 0){
+            tx_sensor_names_str.resize(tx_sensor_names_str.size()-1);
+        }
+
+        memset(sensor_names_out, '\0', strbuffer_len);
+        strncpy(sensor_names_out, tx_sensor_names_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_tx_dc_offset_enabled(
+    uhd_usrp_handle h,
+    bool enb,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_tx_dc_offset(enb, chan);
+    )
+}
+
+uhd_error uhd_usrp_set_tx_iq_balance_enabled(
+    uhd_usrp_handle h,
+    bool enb,
+    size_t chan
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_tx_iq_balance(enb, chan);
+    )
+}
+
+/****************************************************************************
+ * GPIO methods
+ ***************************************************************************/
+
+uhd_error uhd_usrp_get_gpio_banks(
+    uhd_usrp_handle h,
+    size_t chan,
+    char* gpio_banks_out,
+    size_t strbuffer_len,
+    size_t *num_gpio_banks_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> gpio_banks = USRP(h)->get_gpio_banks(chan);
+        *num_gpio_banks_out = gpio_banks.size();
+
+        std::string gpio_banks_str = "";
+        BOOST_FOREACH(const std::string &gpio_bank, gpio_banks){
+            gpio_banks_str += gpio_bank;
+            gpio_banks_str += ',';
+        }
+        if(gpio_banks.size() > 0){
+            gpio_banks_str.resize(gpio_banks_str.size()-1);
+        }
+
+        memset(gpio_banks_out, '\0', strbuffer_len);
+        strncpy(gpio_banks_out, gpio_banks_str.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_set_gpio_attr(
+    uhd_usrp_handle h,
+    const char* bank,
+    const char* attr,
+    uint32_t value,
+    uint32_t mask,
+    size_t mboard
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        USRP(h)->set_gpio_attr(std::string(bank), std::string(attr),
+                               value, mask, mboard);
+    )
+}
+
+uhd_error uhd_usrp_get_gpio_attr(
+    uhd_usrp_handle h,
+    const char* bank,
+    const char* attr,
+    size_t mboard,
+    uint32_t *attr_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *attr_out = USRP(h)->get_gpio_attr(std::string(bank), std::string(attr), mboard);
+    )
+}
diff --git a/host/lib/usrp_clock/CMakeLists.txt b/host/lib/usrp_clock/CMakeLists.txt
index 8a58aa9ac..ba0f5fe0a 100644
--- a/host/lib/usrp_clock/CMakeLists.txt
+++ b/host/lib/usrp_clock/CMakeLists.txt
@@ -1,5 +1,5 @@
 #
-# Copyright 2011-2014 Ettus Research LLC
+# Copyright 2011-2015 Ettus Research LLC
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -23,4 +23,10 @@ LIBUHD_APPEND_SOURCES(
     ${CMAKE_CURRENT_SOURCE_DIR}/multi_usrp_clock.cpp
 )
 
+IF(ENABLE_C_API)
+    LIBUHD_APPEND_SOURCES(
+        ${CMAKE_CURRENT_SOURCE_DIR}/usrp_clock_c.cpp
+    )
+ENDIF(ENABLE_C_API)
+
 INCLUDE_SUBDIRECTORY(octoclock)
diff --git a/host/lib/usrp_clock/usrp_clock_c.cpp b/host/lib/usrp_clock/usrp_clock_c.cpp
new file mode 100644
index 000000000..b55abc852
--- /dev/null
+++ b/host/lib/usrp_clock/usrp_clock_c.cpp
@@ -0,0 +1,175 @@
+/*
+ * Copyright 2015 Ettus Research LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* C-Interface for multi_usrp_clock */
+
+#include <uhd/utils/static.hpp>
+#include <uhd/usrp_clock/multi_usrp_clock.hpp>
+
+#include <uhd/usrp_clock/usrp_clock.h>
+
+#include <boost/foreach.hpp>
+#include <boost/thread/mutex.hpp>
+
+#include <string.h>
+#include <map>
+
+/****************************************************************************
+ * Registry / Pointer Management
+ ***************************************************************************/
+/* Public structs */
+struct uhd_usrp_clock {
+    size_t usrp_clock_index;
+    std::string last_error;
+};
+
+/* Not public: We use this for our internal registry */
+struct usrp_clock_ptr {
+    uhd::usrp_clock::multi_usrp_clock::sptr ptr;
+    static size_t usrp_clock_counter;
+};
+size_t usrp_clock_ptr::usrp_clock_counter = 0;
+typedef struct usrp_clock_ptr usrp_clock_ptr;
+/* Prefer map, because the list can be discontiguous */
+typedef std::map<size_t, usrp_clock_ptr> usrp_clock_ptrs;
+
+UHD_SINGLETON_FCN(usrp_clock_ptrs, get_usrp_clock_ptrs);
+/* Shortcut for accessing the underlying USRP clock sptr from a uhd_usrp_clock_handle* */
+#define USRP_CLOCK(h_ptr) (get_usrp_clock_ptrs()[h_ptr->usrp_clock_index].ptr)
+
+/****************************************************************************
+ * Generate / Destroy API calls
+ ***************************************************************************/
+static boost::mutex _usrp_clock_make_mutex;
+uhd_error uhd_usrp_clock_make(
+    uhd_usrp_clock_handle *h,
+    const char *args
+){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_usrp_clock_make_mutex);
+
+        size_t usrp_clock_count = usrp_clock_ptr::usrp_clock_counter;
+        usrp_clock_ptr::usrp_clock_counter++;
+
+        // Initialize USRP Clock
+        uhd::device_addr_t device_addr(args);
+        usrp_clock_ptr P;
+        P.ptr = uhd::usrp_clock::multi_usrp_clock::make(device_addr);
+
+        // Dump into registry
+        get_usrp_clock_ptrs()[usrp_clock_count] = P;
+
+        // Update handle
+        (*h) = new uhd_usrp_clock;
+        (*h)->usrp_clock_index = usrp_clock_count;
+    )
+}
+
+static boost::mutex _usrp_clock_free_mutex;
+uhd_error uhd_usrp_clock_free(
+    uhd_usrp_clock_handle *h
+){
+    UHD_SAFE_C(
+        boost::mutex::scoped_lock lock(_usrp_clock_free_mutex);
+
+        if(!get_usrp_clock_ptrs().count((*h)->usrp_clock_index)){
+            return UHD_ERROR_INVALID_DEVICE;
+        }
+
+        get_usrp_clock_ptrs().erase((*h)->usrp_clock_index);
+        delete *h;
+        *h = NULL;
+    )
+}
+
+uhd_error uhd_usrp_clock_last_error(
+    uhd_usrp_clock_handle h,
+    char* error_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C(
+        memset(error_out, '\0', strbuffer_len);
+        strncpy(error_out, h->last_error.c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_clock_get_pp_string(
+    uhd_usrp_clock_handle h,
+    char* pp_string_out,
+    size_t strbuffer_len
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        memset(pp_string_out, '\0', strbuffer_len);
+        strncpy(pp_string_out, USRP_CLOCK(h)->get_pp_string().c_str(), strbuffer_len);
+    )
+}
+
+uhd_error uhd_usrp_clock_get_num_boards(
+    uhd_usrp_clock_handle h,
+    size_t *num_boards_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *num_boards_out = USRP_CLOCK(h)->get_num_boards();
+    )
+}
+
+uhd_error uhd_usrp_clock_get_time(
+    uhd_usrp_clock_handle h,
+    size_t board,
+    uint32_t *clock_time_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        *clock_time_out = USRP_CLOCK(h)->get_time(board);
+    )
+}
+
+uhd_error uhd_usrp_clock_get_sensor(
+    uhd_usrp_clock_handle h,
+    const char* name,
+    size_t board,
+    uhd_sensor_value_handle sensor_value_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        delete sensor_value_out->sensor_value_cpp;
+        sensor_value_out->sensor_value_cpp = new uhd::sensor_value_t(USRP_CLOCK(h)->get_sensor(name, board));
+    )
+}
+
+uhd_error uhd_usrp_clock_get_sensor_names(
+    uhd_usrp_clock_handle h,
+    size_t board,
+    char* sensor_names_out,
+    size_t strbuffer_len,
+    size_t *num_sensors_out
+){
+    UHD_SAFE_C_SAVE_ERROR(h,
+        std::vector<std::string> sensor_names = USRP_CLOCK(h)->get_sensor_names(board);
+        *num_sensors_out = sensor_names.size();
+
+        std::string sensor_names_str = "";
+        BOOST_FOREACH(const std::string &sensor_name, sensor_names){
+            sensor_names_str += sensor_name;
+            sensor_names_str += ','; 
+        }
+        if(sensor_names.size() > 0){
+            sensor_names_str.resize(sensor_names_str.size()-1);
+        }
+
+        memset(sensor_names_out, '\0', strbuffer_len);
+        strncpy(sensor_names_out, sensor_names_str.c_str(), strbuffer_len);
+    )    
+}
diff --git a/host/lib/utils/CMakeLists.txt b/host/lib/utils/CMakeLists.txt
index 369920ac1..c5c975dfa 100644
--- a/host/lib/utils/CMakeLists.txt
+++ b/host/lib/utils/CMakeLists.txt
@@ -141,3 +141,9 @@ LIBUHD_APPEND_SOURCES(
     ${CMAKE_CURRENT_SOURCE_DIR}/tasks.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/thread_priority.cpp
 )
+
+IF(ENABLE_C_API)
+    LIBUHD_APPEND_SOURCES(
+        ${CMAKE_CURRENT_SOURCE_DIR}/thread_priority_c.cpp
+    )
+ENDIF(ENABLE_C_API)
diff --git a/host/lib/utils/thread_priority.cpp b/host/lib/utils/thread_priority.cpp
index af25d088a..98023c5aa 100644
--- a/host/lib/utils/thread_priority.cpp
+++ b/host/lib/utils/thread_priority.cpp
@@ -1,5 +1,5 @@
 //
-// Copyright 2010-2011 Ettus Research LLC
+// Copyright 2010-2011,2015 Ettus Research LLC
 //
 // This program is free software: you can redistribute it and/or modify
 // it under the terms of the GNU General Public License as published by
diff --git a/host/lib/utils/thread_priority_c.cpp b/host/lib/utils/thread_priority_c.cpp
new file mode 100644
index 000000000..fe019e51d
--- /dev/null
+++ b/host/lib/utils/thread_priority_c.cpp
@@ -0,0 +1,33 @@
+//
+// Copyright 2015 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <uhd/error.h>
+#include <uhd/utils/thread_priority.h>
+#include <uhd/utils/thread_priority.hpp>
+#include <uhd/utils/msg.hpp>
+#include <uhd/exception.hpp>
+#include <boost/format.hpp>
+#include <iostream>
+
+uhd_error uhd_set_thread_priority(
+    float priority,
+    bool realtime
+){
+    UHD_SAFE_C(
+        uhd::set_thread_priority(priority, realtime);
+    )
+}