diff --git a/library_surveyor.c b/library_surveyor.c
index 9eef65b..8fe4255 100644
--- a/library_surveyor.c
+++ b/library_surveyor.c
@@ -724,6 +724,15 @@ void Cautorun (struct ParseState *Parser, struct Value *ReturnValue, struct Valu
     }
 }
 
+void Clineno (struct ParseState *Parser, struct Value *ReturnValue, struct Value **Param, int NumArgs) {
+    ReturnValue->Val->Integer = Parser->Line;
+}
+
+void Cerrormsg (struct ParseState *Parser, struct Value *ReturnValue, struct Value **Param, int NumArgs) {
+    PlatformErrorPrefix(Parser);
+    LibPrintf(Parser, ReturnValue, Param, NumArgs);
+}
+
 /* list of all library functions and their prototypes */
 struct LibraryFunction PlatformLibrary[] =
 {
@@ -782,6 +791,8 @@ struct LibraryFunction PlatformLibrary[] =
     { Cnnmatchblob, "int nnmatchblob(int)" },
     { Cnnlearnblob, "void nnlearnblob(int)" },
     { Cautorun,     "void autorun(int)" },
+    { Clineno,      "int lineno()" },
+    { Cerrormsg,    "void errormsg(char *)" },
     { NULL,         NULL }
 };
 
diff --git a/library_unix.c b/library_unix.c
index 9c46f3b..9b4ab2b 100644
--- a/library_unix.c
+++ b/library_unix.c
@@ -10,10 +10,21 @@ void Ctest (struct ParseState *Parser, struct Value *ReturnValue, struct Value *
     Param[0]->Val->Integer = 1234;
 }
 
+void Clineno (struct ParseState *Parser, struct Value *ReturnValue, struct Value **Param, int NumArgs) {
+    ReturnValue->Val->Integer = Parser->Line;
+}
+
+void Cerrormsg (struct ParseState *Parser, struct Value *ReturnValue, struct Value **Param, int NumArgs) {
+    PlatformErrorPrefix(Parser);
+    LibPrintf(Parser, ReturnValue, Param, NumArgs);
+}
+
 /* list of all library functions and their prototypes */
 struct LibraryFunction PlatformLibrary[] =
 {
-    { Ctest, "void test(int)" },
+    { Ctest,        "void test(int)" },
+    { Clineno,      "int lineno()" },
+    { Cerrormsg,    "void errorprintf(char *,...)" },
     { NULL,         NULL }
 };
 
diff --git a/picoc.h b/picoc.h
index 9295252..1d5ff86 100644
--- a/picoc.h
+++ b/picoc.h
@@ -379,6 +379,7 @@ void PrintInt(long Num, int FieldWidth, int ZeroPad, int LeftJustify, struct Out
 void PrintStr(const char *Str, struct OutputStream *Stream);
 void PrintFP(double Num, struct OutputStream *Stream);
 void PrintType(struct ValueType *Typ, struct OutputStream *Stream);
+void LibPrintf(struct ParseState *Parser, struct Value *ReturnValue, struct Value **Param, int NumArgs);
 
 /* platform.c */
 void ProgramFail(struct ParseState *Parser, const char *Message, ...);
@@ -389,6 +390,7 @@ void PlatformScanFile(const char *FileName);
 char *PlatformGetLine(char *Buf, int MaxLen);
 int PlatformGetCharacter();
 void PlatformPutc(unsigned char OutCh, union OutputStreamInfo *);
+void PlatformErrorPrefix(struct ParseState *Parser);
 void PlatformPrintf(const char *Format, ...);
 void PlatformVPrintf(const char *Format, va_list Args);
 void PlatformExit();
diff --git a/platform.c b/platform.c
index 4b88cc7..f71a519 100644
--- a/platform.c
+++ b/platform.c
@@ -42,18 +42,23 @@ void PrintSourceTextErrorLine(const char *FileName, const char *SourceText, int
 }
 #endif
 
-/* exit with a message */
-void ProgramFail(struct ParseState *Parser, const char *Message, ...)
+/* display the source line and line number to identify an error */
+void PlatformErrorPrefix(struct ParseState *Parser)
 {
-    va_list Args;
-
     if (Parser != NULL)
 #ifdef FANCY_ERROR_REPORTING
         PrintSourceTextErrorLine(Parser->FileName, Parser->SourceText, Parser->Line, Parser->CharacterPos);
 #else
         PlatformPrintf("%s:%d: ", Parser->FileName, Parser->Line);   
 #endif
-        
+}
+
+/* exit with a message */
+void ProgramFail(struct ParseState *Parser, const char *Message, ...)
+{
+    va_list Args;
+
+    PlatformErrorPrefix(Parser);
     va_start(Args, Message);
     PlatformVPrintf(Message, Args);
     va_end(Args);
@@ -64,13 +69,7 @@ void ProgramFail(struct ParseState *Parser, const char *Message, ...)
 /* like ProgramFail() but gives descriptive error messages for assignment */
 void AssignFail(struct ParseState *Parser, const char *Format, struct ValueType *Type1, struct ValueType *Type2, int Num1, int Num2, const char *FuncName, int ParamNo)
 {
-    if (Parser != NULL)
-#ifdef FANCY_ERROR_REPORTING
-        PrintSourceTextErrorLine(Parser->FileName, Parser->SourceText, Parser->Line, Parser->CharacterPos);
-#else
-        PlatformPrintf("%s:%d: ", Parser->FileName, Parser->Line);   
-#endif
-        
+    PlatformErrorPrefix(Parser);
     PlatformPrintf("can't %s ", (FuncName == NULL) ? "assign" : "set");   
         
     if (Type1 != NULL)