diff --git a/src/main.cpp b/src/main.cpp
index 9e5b015..0724850 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -434,7 +434,9 @@ int main(int argc, char* argv[]){
 
     time_t t1 = time(NULL);
 
-    bool supportEvaluation = !opt.inputFromSTDIN && opt.in1!="/dev/stdin";
+    bool supportEvaluation = !opt.inputFromSTDIN && opt.in1!="/dev/stdin"
+                             && is_regular_file(opt.in1)
+                             && (opt.in2.empty() || is_regular_file(opt.in2));
 
     Evaluator eva(&opt);
     if(supportEvaluation) {
diff --git a/src/util.h b/src/util.h
index 62f582b..0797559 100644
--- a/src/util.h
+++ b/src/util.h
@@ -182,6 +182,15 @@ inline bool is_directory(const  string& path)
     return isdir;
 }
 
+// check if a path is a regular file (seekable), not a pipe/FIFO/device
+inline bool is_regular_file(const  string& path)
+{
+    struct stat status;
+    if( stat( path.c_str(), &status ) != 0 )
+        return false;
+    return S_ISREG( status.st_mode );
+}
+
 inline void check_file_valid(const  string& s) {
     if(!file_exists(s)){
         cerr << "ERROR: file '" << s << "' doesn't exist, quit now" << endl;