Redo TIP #440 alternative again, now using "info runtime".

doc/info.n

@@ -353,6 +353,11 @@ the global namespace if \fIpattern\fR starts with \fB::\fR) to match
 within; the matching pattern is taken to be the part after the last
 namespace separator.
 .TP
+\fBinfo runtime\fR
+.
+Returns the string "core". It can be used to distingush the Tcl "core"
+runtime from other runtimes like TH1 or Eagle.
+.TP
 \fBinfo script\fR ?\fIfilename\fR?
 .
 If a Tcl script file is currently being evaluated (i.e. there is a

generic/tclCmdIL.c

@@ -142,6 +142,8 @@ static int		InfoPatchLevelCmd(ClientData dummy, Tcl_Interp *interp,
 			    int objc, Tcl_Obj *const objv[]);
 static int		InfoProcsCmd(ClientData dummy, Tcl_Interp *interp,
 			    int objc, Tcl_Obj *const objv[]);
+static int		InfoRuntimeCmd(ClientData dummy, Tcl_Interp *interp,
+			    int objc, Tcl_Obj *const objv[]);
 static int		InfoScriptCmd(ClientData dummy, Tcl_Interp *interp,
 			    int objc, Tcl_Obj *const objv[]);
 static int		InfoSharedlibCmd(ClientData dummy, Tcl_Interp *interp,
@@ -181,6 +183,7 @@ static const EnsembleImplMap defaultInfoMap[] = {
     {"nameofexecutable",   InfoNameOfExecutableCmd, TclCompileBasic0ArgCmd, NULL, NULL, 0},
     {"patchlevel",	   InfoPatchLevelCmd,	    TclCompileBasic0ArgCmd, NULL, NULL, 0},
     {"procs",		   InfoProcsCmd,	    TclCompileBasic0Or1ArgCmd, NULL, NULL, 0},
+    {"runtime",		   InfoRuntimeCmd,	    TclCompileBasic0Or1ArgCmd, NULL, NULL, 0},
     {"script",		   InfoScriptCmd,	    TclCompileBasic0Or1ArgCmd, NULL, NULL, 0},
     {"sharedlibextension", InfoSharedlibCmd,	    TclCompileBasic0ArgCmd, NULL, NULL, 0},
     {"tclversion",	   InfoTclVersionCmd,	    TclCompileBasic0ArgCmd, NULL, NULL, 0},
@@ -2001,6 +2004,42 @@ InfoProcsCmd(
     return TCL_OK;
 }
 
+/*
+ *----------------------------------------------------------------------
+ *
+ * InfoRuntimeCmd --
+ *
+ *	Called to implement the "info runtime" command that returns the
+ *	runtime. For the Tcl Core implementation, it always returns "core".
+ *  Handles the following syntax:
+ *
+ *	    info runtime
+ *
+ * Results:
+ *	Returns TCL_OK.
+ *
+ * Side effects:
+ *	Returns a result ("core") in the interpreter's result object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+InfoRuntimeCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    if (objc != 1) {
+	Tcl_WrongNumArgs(interp, 1, objv, NULL);
+	return TCL_ERROR;
+    }
+
+    Tcl_SetObjResult(interp, Tcl_NewStringObj("core", -1));
+    return TCL_OK;
+}
+
 /*
  *----------------------------------------------------------------------
  *

tests/info.test

@@ -678,16 +678,16 @@ test info-21.1 {miscellaneous error conditions} -returnCodes error -body {
 } -result {wrong # args: should be "info subcommand ?arg ...?"}
 test info-21.2 {miscellaneous error conditions} -returnCodes error -body {
     info gorp
-} -result {unknown or ambiguous subcommand "gorp": must be args, body, class, cmdcount, commands, complete, coroutine, default, errorstack, exists, frame, functions, globals, hostname, level, library, loaded, locals, nameofexecutable, object, patchlevel, procs, script, sharedlibextension, tclversion, or vars}
+} -result {unknown or ambiguous subcommand "gorp": must be args, body, class, cmdcount, commands, complete, coroutine, default, errorstack, exists, frame, functions, globals, hostname, level, library, loaded, locals, nameofexecutable, object, patchlevel, procs, runtime, script, sharedlibextension, tclversion, or vars}
 test info-21.3 {miscellaneous error conditions} -returnCodes error -body {
     info c
-} -result {unknown or ambiguous subcommand "c": must be args, body, class, cmdcount, commands, complete, coroutine, default, errorstack, exists, frame, functions, globals, hostname, level, library, loaded, locals, nameofexecutable, object, patchlevel, procs, script, sharedlibextension, tclversion, or vars}
+} -result {unknown or ambiguous subcommand "c": must be args, body, class, cmdcount, commands, complete, coroutine, default, errorstack, exists, frame, functions, globals, hostname, level, library, loaded, locals, nameofexecutable, object, patchlevel, procs, runtime, script, sharedlibextension, tclversion, or vars}
 test info-21.4 {miscellaneous error conditions} -returnCodes error -body {
     info l
-} -result {unknown or ambiguous subcommand "l": must be args, body, class, cmdcount, commands, complete, coroutine, default, errorstack, exists, frame, functions, globals, hostname, level, library, loaded, locals, nameofexecutable, object, patchlevel, procs, script, sharedlibextension, tclversion, or vars}
+} -result {unknown or ambiguous subcommand "l": must be args, body, class, cmdcount, commands, complete, coroutine, default, errorstack, exists, frame, functions, globals, hostname, level, library, loaded, locals, nameofexecutable, object, patchlevel, procs, runtime, script, sharedlibextension, tclversion, or vars}
 test info-21.5 {miscellaneous error conditions} -returnCodes error -body {
     info s
-} -result {unknown or ambiguous subcommand "s": must be args, body, class, cmdcount, commands, complete, coroutine, default, errorstack, exists, frame, functions, globals, hostname, level, library, loaded, locals, nameofexecutable, object, patchlevel, procs, script, sharedlibextension, tclversion, or vars}
+} -result {unknown or ambiguous subcommand "s": must be args, body, class, cmdcount, commands, complete, coroutine, default, errorstack, exists, frame, functions, globals, hostname, level, library, loaded, locals, nameofexecutable, object, patchlevel, procs, runtime, script, sharedlibextension, tclversion, or vars}
 
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