no error on missing init file

app/Main.cc

@@ -20,7 +20,6 @@
 #include <tcl.h>
 
 #include "StaConfig.hh"  // STA_VERSION
-#include "StringUtil.hh"
 #include "Sta.hh"
 
 
@@ -28,15 +27,16 @@ namespace sta {
 extern const char *tcl_inits[];
 }
 
+using std::string;
 using sta::stringEq;
 using sta::findCmdLineFlag;
 using sta::Sta;
 using sta::initSta;
 using sta::evalTclInit;
-using sta::stringPrintTmp;
 using sta::sourceTclFile;
 using sta::parseThreadsArg;
 using sta::tcl_inits;
+using sta::is_regular_file;
 
 // Swig uses C linkage for init functions.
 extern "C" {
@@ -116,9 +116,11 @@ staTclAppInit(int argc,
     Tcl_Eval(interp, "sta::show_splash");
 
   if (!findCmdLineFlag(argc, argv, "-no_init")) {
-    char *init_path = stringPrintTmp("[file join $env(HOME) %s]",
-				     init_filename);
-    sourceTclFile(init_path, true, true, interp);
+    string init_path = getenv("HOME");
+    init_path += "/";
+    init_path += init_filename;
+    if (is_regular_file(init_path.c_str()))
+      sourceTclFile(init_path.c_str(), true, true, interp);
   }
 
   bool exit_after_cmd_file = findCmdLineFlag(argc, argv, "-exit");

app/StaMain.cc

@@ -18,6 +18,7 @@
 
 #include <tcl.h>
 #include <stdlib.h>
+#include <sys/stat.h>
 
 #include "StringUtil.hh"
 #include "Vector.hh"
@@ -139,4 +140,12 @@ unencode(const char *inits[])
   return unencoded;
 }
 
+// Hack until c++17 filesystem is better supported.
+bool
+is_regular_file(const char *filename)
+{
+  struct stat sb;
+  return stat(filename, &sb) == 0 && S_ISREG(sb.st_mode);
+}
+
 } // namespace

include/sta/StaMain.hh

@@ -62,5 +62,7 @@ sourceTclFile(const char *filename,
 	      bool echo,
 	      bool verbose,
 	      Tcl_Interp *interp);
+bool
+is_regular_file(const char *filename);
 
 } // namespace