Adding search_env_path in radixcore/system.

radixcore/system.cc

@@ -366,6 +366,33 @@ bool remove_file(const std::string &path)
 {
   if (dir_exists(path)) return false;
   return remove(path.c_str()) == 0;
-}  // remove_file
+}
+
+std::string search_env_path(const std::string &filename)
+{
+  std::string path_env          = env("PATH");
+  std::vector<std::string> list = split_string(":", path_env);
+  if (list.size() == 1)  // we didn't split anything
+  {
+    // guess it was ':' separator, try ';'
+    list = split_string(";", path_env);
+  }
+  for (size_t i = 0; i < list.size(); ++i)
+  {
+    std::string item = list[i];
+    item             = item + separator_char();
+    radix_line("Searching " << item << " for " << filename);
+    std::string path = item + filename;
+    if (file_exists(path))
+    {
+      radix_line("Found " << path);
+      return path;
+    }
+  }
+  radix_line("Did not find " << filename << " on the PATH");
+  return std::string();
+}
+
+// remove_file
 
 }  // namespace radix

radixcore/system.hh

@@ -192,6 +192,13 @@ RADIX_PUBLIC bool remove_dir(const std::string &path);
  */
 RADIX_PUBLIC bool remove_file(const std::string &path);
 
+/**
+ * @brief search_env_path Search the environment variable PATH for the filename
+ * @param filename filename to search for
+ * @return The PATH prefix if the filename is found to exist or empty.
+ */
+RADIX_PUBLIC std::string search_env_path(const std::string &filename);
+
 }  // namespace radix
 
 #endif /** RADIX_RADIXCORE_SYSTEM_HH_ */