Index: apertium/apertium_perceptron_trace.cc
--- apertium/apertium_perceptron_trace.cc.orig
+++ apertium/apertium_perceptron_trace.cc
@@ -1,5 +1,6 @@
 #include <fstream>
 #include <string>
+#include <unistd.h>
 
 #include <apertium/mtx_reader.h>
 #include <apertium/perceptron_tagger.h>
@@ -109,5 +110,11 @@ int perceptron_trace(int argc, char* argv[])
 
 
 int main(int argc, char* argv[]) {
+  if (pledge("stdio rpath wpath cpath", NULL) == -1)
+  {
+    std::wcout << "pledge" << std::endl;
+    return 1;
+  }
+
   return Apertium::perceptron_trace(argc, argv);
 }