* generic/tclInt.decls:

	* generic/tclIntPlatDecls.h:
	* mac/tclMacChan.c:
	* mac/tclMacFCmd.c:
	* mac/tclMacFile.c:
	* mac/tclMacInit.c:
	* mac/tclMacLoad.c:
	* mac/tclMacResource.c:
	* mac/tclMacSock.c: TIP 27 CONSTification induced changes

	* tests/event.test:
	* tests/main.test: added catches/constraints to test that
	use features that don't exist on the mac.

12 files changed, 98 insertions, 71 deletions

diff --git a/ChangeLog b/ChangeLog
index ab42573..52e7b4d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,19 @@
+2001-01-27  Daniel Steffen  <das@users.sourceforge.net>
+
+	* generic/tclInt.decls:
+	* generic/tclIntPlatDecls.h:
+	* mac/tclMacChan.c:
+	* mac/tclMacFCmd.c:
+	* mac/tclMacFile.c:
+	* mac/tclMacInit.c:
+	* mac/tclMacLoad.c:
+	* mac/tclMacResource.c:
+	* mac/tclMacSock.c: TIP 27 CONSTification induced changes
+
+	* tests/event.test:
+	* tests/main.test: added catches/constraints to test that
+	use features that don't exist on the mac.
+
 2002-01-25  Mo DeJong  <mdejong@users.sourceforge.net>
 
 	Make -eofchar and -translation options read only for
diff --git a/generic/tclInt.decls b/generic/tclInt.decls
index 008b1d3..67bd6f7 100644
--- a/generic/tclInt.decls
+++ b/generic/tclInt.decls
@@ -12,7 +12,7 @@
 # See the file "license.terms" for information on usage and redistribution
 # of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 # 
-# RCS: @(#) $Id: tclInt.decls,v 1.44 2002/01/25 22:01:31 dgp Exp $
+# RCS: @(#) $Id: tclInt.decls,v 1.45 2002/01/27 11:09:30 das Exp $
 
 library tcl
 
@@ -780,7 +780,7 @@ declare 24 mac {
     char * TclpGetTZName(int isdst)
 }
 declare 25 mac {
-    int TclMacChmod(char *path, int mode)
+    int TclMacChmod(CONST char *path, int mode)
 }
 
 ############################
diff --git a/generic/tclIntPlatDecls.h b/generic/tclIntPlatDecls.h
index 3ddaf22..907a648 100644
--- a/generic/tclIntPlatDecls.h
+++ b/generic/tclIntPlatDecls.h
@@ -9,7 +9,7 @@
  * Copyright (c) 1998-1999 by Scriptics Corporation.
  * All rights reserved.
  *
- * RCS: @(#) $Id: tclIntPlatDecls.h,v 1.15 2002/01/25 20:40:55 dgp Exp $
+ * RCS: @(#) $Id: tclIntPlatDecls.h,v 1.16 2002/01/27 11:09:34 das Exp $
  */
 
 #ifndef _TCLINTPLATDECLS
@@ -197,7 +197,7 @@ EXTERN FILE *		TclMacFOpenHack _ANSI_ARGS_((CONST char * path,
 /* 24 */
 EXTERN char *		TclpGetTZName _ANSI_ARGS_((int isdst));
 /* 25 */
-EXTERN int		TclMacChmod _ANSI_ARGS_((char * path, int mode));
+EXTERN int		TclMacChmod _ANSI_ARGS_((CONST char * path, int mode));
 #endif /* MAC_TCL */
 
 typedef struct TclIntPlatStubs {
@@ -272,7 +272,7 @@ typedef struct TclIntPlatStubs {
     int (*tclMacCreateEnv) _ANSI_ARGS_((void)); /* 22 */
     FILE * (*tclMacFOpenHack) _ANSI_ARGS_((CONST char * path, CONST char * mode)); /* 23 */
     char * (*tclpGetTZName) _ANSI_ARGS_((int isdst)); /* 24 */
-    int (*tclMacChmod) _ANSI_ARGS_((char * path, int mode)); /* 25 */
+    int (*tclMacChmod) _ANSI_ARGS_((CONST char * path, int mode)); /* 25 */
 #endif /* MAC_TCL */
 } TclIntPlatStubs;
 
diff --git a/mac/tclMacChan.c b/mac/tclMacChan.c
index da74176..90be8a4 100644
--- a/mac/tclMacChan.c
+++ b/mac/tclMacChan.c
@@ -9,7 +9,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclMacChan.c,v 1.11 2002/01/18 03:22:36 das Exp $
+ * RCS: @(#) $Id: tclMacChan.c,v 1.12 2002/01/27 11:09:38 das Exp $
  */
 
 #include "tclInt.h"
@@ -1282,7 +1282,7 @@ GetOpenMode(
 					 * "RDONLY CREAT". */
 {
     int mode, modeArgc, c, i, gotRW;
-    char **modeArgv, *flag;
+    CONST char **modeArgv, *flag;
 
     /*
      * Check for the simpler fopen-like access modes (e.g. "r").  They
diff --git a/mac/tclMacFCmd.c b/mac/tclMacFCmd.c
index 528f5fc..1a75ce7 100644
--- a/mac/tclMacFCmd.c
+++ b/mac/tclMacFCmd.c
@@ -9,7 +9,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclMacFCmd.c,v 1.15 2002/01/26 01:10:08 dgp Exp $
+ * RCS: @(#) $Id: tclMacFCmd.c,v 1.16 2002/01/27 11:09:44 das Exp $
  */
 
 #include "tclInt.h"
@@ -1024,7 +1024,7 @@ GetFileSpecs(
     Boolean *pathIsDirectoryPtr)/* Set to true if path is itself a directory,
     				 * otherwise false. */
 {
-    char *dirName;
+    CONST char *dirName;
     OSErr err;
     int argc;
     CONST char **argv;
diff --git a/mac/tclMacFile.c b/mac/tclMacFile.c
index 921ada5..522372a 100644
--- a/mac/tclMacFile.c
+++ b/mac/tclMacFile.c
@@ -10,7 +10,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclMacFile.c,v 1.15 2002/01/25 20:40:56 dgp Exp $
+ * RCS: @(#) $Id: tclMacFile.c,v 1.16 2002/01/27 11:09:49 das Exp $
  */
 
 /*
@@ -610,25 +610,23 @@ TclpReadlink(
     Handle theString = NULL;
     int pathSize;
     Tcl_DString ds;
-    char *native;
     
-    native = Tcl_UtfToExternalDString(NULL, path, -1, &ds);
+    Tcl_UtfToExternalDString(NULL, path, -1, &ds);
 
     /*
      * Remove ending colons if they exist.
      */
      
-    while ((strlen(native) != 0) && (path[strlen(native) - 1] == ':')) {
-	native[strlen(native) - 1] = NULL;
+    while ((Tcl_DStringLength(&ds) != 0) && (Tcl_DStringValue(&ds)[Tcl_DStringLength(&ds) - 1] == ':')) {
+	Tcl_DStringSetLength(&ds, Tcl_DStringLength(&ds) - 1);
     }
 
-    if (strchr(native, ':') == NULL) {
-	strcpy(fileName + 1, native);
-	native = NULL;
+    end = strrchr(Tcl_DStringValue(&ds), ':');
+    if (end == NULL ) {
+	strcpy(fileName + 1, Tcl_DStringValue(&ds));
     } else {
-	end = strrchr(native, ':') + 1;
-	strcpy(fileName + 1, end);
-	*end = NULL;
+	strcpy(fileName + 1, end + 1);
+	Tcl_DStringSetLength(&ds, end + 1 - Tcl_DStringValue(&ds));
     }
     fileName[0] = (char) strlen(fileName + 1);
     
@@ -637,8 +635,8 @@ TclpReadlink(
      * we want to look at.
      */
 
-    if (native != NULL) {
-	err = FSpLocationFromPath(strlen(native), native, &fileSpec);
+    if (end != NULL) {
+	err = FSpLocationFromPath(Tcl_DStringLength(&ds), Tcl_DStringValue(&ds), &fileSpec);
 	if (err != noErr) {
 	    Tcl_DStringFree(&ds);
 	    errno = EINVAL;
@@ -904,7 +902,7 @@ TclMacFOpenHack(
     int size;
     FILE * f;
     
-    err = FSpLocationFromPath(strlen(path), (char *) path, &fileSpec);
+    err = FSpLocationFromPath(strlen(path), path, &fileSpec);
     if ((err != noErr) && (err != fnfErr)) {
 	return NULL;
     }
@@ -1007,14 +1005,15 @@ TclMacOSErrorToPosixError(
 
 int
 TclMacChmod(
-    char *path, 
+    CONST char *path, 
     int mode)
 {
     HParamBlockRec hpb;
     OSErr err;
-    
-    c2pstr(path);
-    hpb.fileParam.ioNamePtr = (unsigned char *) path;
+    Str255 pathName;
+    strcpy((char *) pathName + 1, path);
+    pathName[0] = strlen(path);
+    hpb.fileParam.ioNamePtr = pathName;
     hpb.fileParam.ioVRefNum = 0;
     hpb.fileParam.ioDirID = 0;
     
@@ -1023,7 +1022,6 @@ TclMacChmod(
     } else {
         err = PBHSetFLockSync(&hpb);
     }
-    p2cstr((unsigned char *) path);
     
     if (err != noErr) {
         errno = TclMacOSErrorToPosixError(err);
diff --git a/mac/tclMacInit.c b/mac/tclMacInit.c
index 451e377..8cfe2b5 100644
--- a/mac/tclMacInit.c
+++ b/mac/tclMacInit.c
@@ -8,7 +8,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclMacInit.c,v 1.7 2002/01/25 20:40:56 dgp Exp $
+ * RCS: @(#) $Id: tclMacInit.c,v 1.8 2002/01/27 11:09:54 das Exp $
  */
 
 #include <AppleEvents.h>
@@ -537,7 +537,7 @@ TclpSetVariables(interp)
     int minor, major, objc;
     Tcl_Obj **objv;
     char versStr[2 * TCL_INTEGER_SPACE];
-    char *str;
+    CONST char *str;
     Tcl_Obj *pathPtr;
     Tcl_DString ds;
 
@@ -781,9 +781,13 @@ Tcl_SourceRCFile(
     fileName = Tcl_GetVar(interp, "tcl_rcRsrcName", TCL_GLOBAL_ONLY);
 
     if (fileName != NULL) {
-	c2pstr(fileName);
-	h = GetNamedResource('TEXT', (StringPtr) fileName);
-	p2cstr((StringPtr) fileName);
+	Str255 rezName;
+	Tcl_DString ds;
+	Tcl_UtfToExternalDString(NULL, fileName, -1, &ds);
+	strcpy((char *) rezName + 1, Tcl_DStringValue(&ds));
+	rezName[0] = (unsigned) Tcl_DStringLength(&ds);
+	h = GetNamedResource('TEXT', rezName);
+	Tcl_DStringFree(&ds);
 	if (h != NULL) {
 	    if (Tcl_MacEvalResource(interp, fileName, 0, NULL) != TCL_OK) {
 		errChannel = Tcl_GetStdChannel(TCL_STDERR);
diff --git a/mac/tclMacLoad.c b/mac/tclMacLoad.c
index 1082a23..e767651 100644
--- a/mac/tclMacLoad.c
+++ b/mac/tclMacLoad.c
@@ -10,7 +10,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclMacLoad.c,v 1.11 2002/01/18 03:22:58 das Exp $
+ * RCS: @(#) $Id: tclMacLoad.c,v 1.12 2002/01/27 11:09:58 das Exp $
  */
 
 #include <CodeFragments.h>
@@ -126,11 +126,11 @@ TclpLoadFile(
     UInt32 offset = 0;
     UInt32 length = kCFragGoesToEOF;
     StringPtr fragName=NULL;
-    Str255 errName;
+    Str255 errName, symbolName;
     Tcl_DString ds;
-    char *native;
+    CONST char *native;
     
-    native = (char *) Tcl_FSGetNativePath(pathPtr);
+    native = Tcl_FSGetNativePath(pathPtr);
     err = FSpLocationFromPath(strlen(native), native, &fileSpec);
     
     if (err != noErr) {
@@ -145,7 +145,7 @@ TclpLoadFile(
      * it to us.
      */
     native = Tcl_UtfToExternalDString(NULL, sym1, -1, &ds);
-    native[strlen(native) - 5] = 0;
+    Tcl_DStringSetLength(&ds, Tcl_DStringLength(&ds) - 5);
     
     /*
      * See if this fragment has a 'cfrg' resource.  It will tell us where
@@ -215,9 +215,10 @@ TclpLoadFile(
     
     *unloadProcPtr = &TclpUnloadFile;
    
-    native = Tcl_UtfToExternalDString(NULL, sym1, -1, &ds);
-    c2pstr(native);
-    err = FindSymbol(connID, (StringPtr) native, (Ptr *) proc1Ptr, &symClass);
+    Tcl_UtfToExternalDString(NULL, sym1, -1, &ds);
+    strcpy((char *) symbolName + 1, Tcl_DStringValue(&ds));
+    symbolName[0] = (unsigned) Tcl_DStringLength(&ds);
+    err = FindSymbol(connID, symbolName, (Ptr *) proc1Ptr, &symClass);
     Tcl_DStringFree(&ds);
     if (err != fragNoErr || symClass == kDataCFragSymbol) {
 	Tcl_SetResult(interp,
@@ -226,9 +227,10 @@ TclpLoadFile(
 	return TCL_ERROR;
     }
 
-    native = Tcl_UtfToExternalDString(NULL, sym2, -1, &ds);
-    c2pstr(native);
-    err = FindSymbol(connID, (StringPtr) native, (Ptr *) proc2Ptr, &symClass);
+    Tcl_UtfToExternalDString(NULL, sym2, -1, &ds);
+    strcpy((char *) symbolName + 1, Tcl_DStringValue(&ds));
+    symbolName[0] = (unsigned) Tcl_DStringLength(&ds);
+    err = FindSymbol(connID, symbolName, (Ptr *) proc2Ptr, &symClass);
     Tcl_DStringFree(&ds);
     if (err != fragNoErr || symClass == kDataCFragSymbol) {
 	*proc2Ptr = NULL;
diff --git a/mac/tclMacResource.c b/mac/tclMacResource.c
index 4e29420..671aea1 100644
--- a/mac/tclMacResource.c
+++ b/mac/tclMacResource.c
@@ -11,7 +11,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclMacResource.c,v 1.11 2002/01/26 01:10:08 dgp Exp $
+ * RCS: @(#) $Id: tclMacResource.c,v 1.12 2002/01/27 11:10:03 das Exp $
  */
 
 #include <Errors.h>
@@ -496,7 +496,7 @@ resourceRef? resourceType");
 	    return TCL_OK;
 	case RESOURCE_OPEN: {
 	    Tcl_DString ds, buffer;
-	    char *str, *native;
+	    CONST char *str, *native;
 	    int length;
 	    			
 	    if (!((objc == 3) || (objc == 4))) {
@@ -1293,9 +1293,12 @@ Tcl_MacEvalResource(
      * Load the resource by name or ID
      */
     if (resourceName != NULL) {
-	strcpy((char *) rezName + 1, resourceName);
-	rezName[0] = strlen(resourceName);
+	Tcl_DString ds;
+	Tcl_UtfToExternalDString(NULL, resourceName, -1, &ds);
+	strcpy((char *) rezName + 1, Tcl_DStringValue(&ds));
+	rezName[0] = (unsigned) Tcl_DStringLength(&ds);
 	sourceText = GetNamedResource('TEXT', rezName);
+	Tcl_DStringFree(&ds);
     } else {
 	sourceText = GetResource('TEXT', (short) resourceNumber);
     }
@@ -1462,15 +1465,17 @@ Tcl_MacFindResource(
 	    resource = GetResource(resourceType, resourceNumber);
 	}
     } else {
+    	Str255 rezName;
 	Tcl_DString ds;
-	char *native = Tcl_UtfToExternalDString(NULL, resourceName, -1, &ds);
-	c2pstr(native);
+	Tcl_UtfToExternalDString(NULL, resourceName, -1, &ds);
+	strcpy((char *) rezName + 1, Tcl_DStringValue(&ds));
+	rezName[0] = (unsigned) Tcl_DStringLength(&ds);
 	if (limitSearch) {
 	    resource = Get1NamedResource(resourceType,
-		    (StringPtr) native);
+		    rezName);
 	} else {
 	    resource = GetNamedResource(resourceType,
-		    (StringPtr) resourceName);
+		    rezName);
 	}
 	Tcl_DStringFree(&ds);
     }
diff --git a/mac/tclMacSock.c b/mac/tclMacSock.c
index 7112ee3..70380b1 100644
--- a/mac/tclMacSock.c
+++ b/mac/tclMacSock.c
@@ -8,7 +8,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclMacSock.c,v 1.11 2002/01/23 20:46:01 dgp Exp $
+ * RCS: @(#) $Id: tclMacSock.c,v 1.12 2002/01/27 11:10:07 das Exp $
  */
 
 #include "tclInt.h"
@@ -2449,7 +2449,7 @@ GetHostFromString(
     }
     dnrState.done = 0;
     GetCurrentProcess(&(dnrState.psn));
-    err = StrToAddr(name, &dnrState.hostInfo, resultUPP, (Ptr) &dnrState);
+    err = StrToAddr((char*)name, &dnrState.hostInfo, resultUPP, (Ptr) &dnrState);
     if (err == cacheFault) {
 	while (!dnrState.done) {
 	    WaitNextEvent(0, &dummy, 1, NULL);
@@ -2464,7 +2464,7 @@ GetHostFromString(
 
     if (dnrState.hostInfo.rtnCode == cacheFault) {
 	dnrState.done = 0;
-	err = StrToAddr(name, &dnrState.hostInfo, resultUPP, (Ptr) &dnrState);
+	err = StrToAddr((char*)name, &dnrState.hostInfo, resultUPP, (Ptr) &dnrState);
 	if (err == cacheFault) {
 	    while (!dnrState.done) {
 		WaitNextEvent(0, &dummy, 1, NULL);
diff --git a/tests/event.test b/tests/event.test
index ce9e34d..2afd33e 100644
--- a/tests/event.test
+++ b/tests/event.test
@@ -9,7 +9,7 @@
 # See the file "license.terms" for information on usage and redistribution
 # of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 #
-# RCS: @(#) $Id: event.test,v 1.14 2001/12/10 20:30:13 msofer Exp $
+# RCS: @(#) $Id: event.test,v 1.15 2002/01/27 11:09:23 das Exp $
 
 if {[lsearch [namespace children] ::tcltest] == -1} {
     package require tcltest
@@ -276,7 +276,9 @@ test event-7.4 {tkerror is nothing special anymore to tcl} {
     set errRes
 } bg:err1
 
-test event-7.5 {correct behaviour when there is no bgerror [Bug 219142]} {
+testConstraint exec [llength [info commands exec]]
+
+test event-7.5 {correct behaviour when there is no bgerror [Bug 219142]} {exec} {
     set script {
 	after 1000 error hello
 	after 2000 set a 0
diff --git a/tests/main.test b/tests/main.test
index 18d3ea3..d1d5196 100644
--- a/tests/main.test
+++ b/tests/main.test
@@ -1,6 +1,6 @@
 # This file contains a collection of tests for generic/tclMain.c.
 #
-# RCS: @(#) $Id: main.test,v 1.3 2002/01/09 19:03:34 dgp Exp $
+# RCS: @(#) $Id: main.test,v 1.4 2002/01/27 11:09:26 das Exp $
 
 if {[catch {package require tcltest 2}]} {
     puts stderr "Skipping tests in [info script]. tcltest v2 needed."
@@ -46,7 +46,7 @@ namespace eval ::tcl::main::test {
 	Tcl_Main: startup script - normal
     } -constraints [list exec] -setup {
 	makeFile {puts [list $argv0 $argv $tcl_interactive]} script
-	set f [open "|[interpreter] script" r]
+	catch {set f [open "|[interpreter] script" r]}
     } -body {
 	read $f
     } -cleanup {
@@ -58,7 +58,7 @@ namespace eval ::tcl::main::test {
 	Tcl_Main: startup script - can't begin with '-'
     } -constraints [list exec] -setup {
 	makeFile {puts [list $argv0 $argv $tcl_interactive]} -script
-	set f [open "|[interpreter] -script" w+]
+	catch {set f [open "|[interpreter] -script" w+]}
     } -body {
 	puts $f {puts [list $argv0 $argv $tcl_interactive]; exit}
 	flush $f
@@ -73,7 +73,7 @@ namespace eval ::tcl::main::test {
 	Note the shortcoming explained in Tcl Patch 491789
     } -constraints [list exec] -setup {
 	makeFile {puts [list $argv0 $argv $tcl_interactive]} script
-	set f [open "|[interpreter] script \u00c0" r]
+	catch {set f [open "|[interpreter] script \u00c0" r]}
     } -body {
 	read $f
     } -cleanup {
@@ -87,7 +87,7 @@ namespace eval ::tcl::main::test {
 	Note the shortcoming explained in Tcl Patch 491789
     } -constraints [list exec] -setup {
 	makeFile {puts [list $argv0 $argv $tcl_interactive]} script
-	set f [open "|[interpreter] script \u20ac" r]
+	catch {set f [open "|[interpreter] script \u20ac" r]}
     } -body {
 	read $f
     } -cleanup {
@@ -101,7 +101,7 @@ namespace eval ::tcl::main::test {
 	Note the shortcoming explained in Tcl Patch 491789
     } -constraints [list exec] -setup {
 	makeFile {puts [list $argv0 $argv $tcl_interactive]} \u00c0
-	set f [open "|[interpreter] \u00c0" r]
+	catch {set f [open "|[interpreter] \u00c0" r]}
     } -body {
 	read $f
     } -cleanup {
@@ -115,7 +115,7 @@ namespace eval ::tcl::main::test {
 	Note the shortcoming explained in Tcl Patch 491789
     } -constraints [list exec] -setup {
 	makeFile {puts [list $argv0 $argv $tcl_interactive]} \u20ac
-	set f [open "|[interpreter] \u20ac" r]
+	catch {set f [open "|[interpreter] \u20ac" r]}
     } -body {
 	read $f
     } -cleanup {
@@ -462,7 +462,7 @@ namespace eval ::tcl::main::test {
     test Tcl_Main-5.2 {
 	Tcl_Main able to handle non-blocking stdin
     } -constraints [list exec] -setup {
-	set f [open "|[interpreter]" w+]
+	catch {set f [open "|[interpreter]" w+]}
     } -body {
 	type $f {
 	    fconfigure stdin -blocking 0
@@ -476,8 +476,8 @@ namespace eval ::tcl::main::test {
     test Tcl_Main-5.3 {
 	Tcl_Main handles stdin EOF in mid-command
     } -constraints [list exec] -setup {
-	set f [open "|[interpreter]" w+]
-	fconfigure $f -blocking 0
+	catch {set f [open "|[interpreter]" w+]}
+	catch {fconfigure $f -blocking 0}
     } -body {
 	type $f "fconfigure stdin -eofchar \\032
 	    if 1 \{\n\032"
@@ -499,8 +499,8 @@ namespace eval ::tcl::main::test {
 	Tcl_Main handles stdin EOF in mid-command
     } -constraints [list exec] -setup {
 	set cmd {makeFile "if 1 \{" script}
-	set f [open "|[interpreter] < [eval $cmd]" r]
-	fconfigure $f -blocking 0
+	catch {set f [open "|[interpreter] < [eval $cmd]" r]}
+	catch {fconfigure $f -blocking 0}
     } -body {
 	variable wait
 	fileevent $f readable \
@@ -604,8 +604,8 @@ namespace eval ::tcl::main::test {
     test Tcl_Main-5.10 {
 	Tcl_Main: exit main loop in mid-interactive command
     } -constraints [list exec Tcltest] -setup {
-	set f [open "|[interpreter]" w+]
-	fconfigure $f -blocking 0
+	catch {set f [open "|[interpreter]" w+]}
+	catch {fconfigure $f -blocking 0}
     } -body {
 	type $f "testsetmainloop
 	         after 2000 testexitmainloop