6 files changed, 31 insertions, 5 deletions
diff --git a/doc/example.ini b/doc/example.ini
index 6e71d4a..eda50a5 100644
--- a/doc/example.ini
+++ b/doc/example.ini
@@ -1,5 +1,12 @@
 ; Sample configuration file for ODR-DabMod
 
+[general]
+; Before starting up, run this command, and abort if it doesn't return 0.
+; This is useful to ensure that NTP has properly synchronised time.
+startupcheck=
+;startupcheck=chronyc waitsync 10 0.01
+;startupcheck=ntp-wait -fv
+
 [remotecontrol]
 ; The RC feature is described in detail in doc/README-RC.md
 
diff --git a/src/ConfigParser.cpp b/src/ConfigParser.cpp
index 1219ae7..4a1e362 100644
--- a/src/ConfigParser.cpp
+++ b/src/ConfigParser.cpp
@@ -80,6 +80,8 @@ static void parse_configfile(
         throw std::runtime_error("Cannot read configuration file");
     }
 
+    mod_settings.startupCheck = pt.Get("general.startupcheck", "");
+
     // remote controller interfaces:
     if (pt.GetInteger("remotecontrol.telnet", 0) == 1) {
         try {
diff --git a/src/ConfigParser.h b/src/ConfigParser.h
index d35432b..ae76dee 100644
--- a/src/ConfigParser.h
+++ b/src/ConfigParser.h
@@ -34,13 +34,11 @@
 #include <string>
 #include "GainControl.h"
 #include "TII.h"
-#include "output/SDR.h"
-#include "output/UHD.h"
-#include "output/Soapy.h"
-#include "output/Lime.h"
-#include "output/BladeRF.h"
+#include "output/SDRDevice.h"
 
 struct mod_settings_t {
+    std::string startupCheck;
+
     std::string outputName;
     bool useZeroMQOutput = false;
     std::string zmqOutputSocketType = "";
diff --git a/src/DabMod.cpp b/src/DabMod.cpp
index 648b7ad..f238ca4 100644
--- a/src/DabMod.cpp
+++ b/src/DabMod.cpp
@@ -394,6 +394,25 @@ int launch_modulator(int argc, char* argv[])
         throw std::runtime_error("Configuration error: Output not specified");
     }
 
+    if (not mod_settings.startupCheck.empty()) {
+        etiLog.level(info) << "Running startup check '" << mod_settings.startupCheck << "'";
+        int wstatus = system(mod_settings.startupCheck.c_str());
+
+        if (WIFEXITED(wstatus)) {
+            if (WEXITSTATUS(wstatus) == 0) {
+                etiLog.level(info) << "Startup check ok";
+            }
+            else {
+                etiLog.level(error) << "Startup check failed, returned " << WEXITSTATUS(wstatus);
+                return 1;
+            }
+        }
+        else {
+            etiLog.level(error) << "Startup check failed, child didn't terminate normally";
+            return 1;
+        }
+    }
+
     printModSettings(mod_settings);
 
     ModulatorData m;
diff --git a/src/output/BladeRF.cpp b/src/output/BladeRF.cpp
index c16b64d..c16b64d 100755..100644
--- a/src/output/BladeRF.cpp
+++ b/src/output/BladeRF.cpp
diff --git a/src/output/BladeRF.h b/src/output/BladeRF.h
index fa3419e..fa3419e 100755..100644
--- a/src/output/BladeRF.h
+++ b/src/output/BladeRF.h