merge 8.7

generic/tclIO.c

@@ -8925,8 +8925,8 @@ Tcl_FileEventObjCmd(
     const char *chanName;
     int modeIndex;		/* Index of mode argument. */
     int mask;
-    static const char *const modeOptions[] = {"readable", "writable", NULL};
-    static const int maskArray[] = {TCL_READABLE, TCL_WRITABLE};
+    static const char *const modeOptions[] = {"readable", "writable", "exception", NULL};
+    static const int maskArray[] = {TCL_READABLE, TCL_WRITABLE, TCL_EXCEPTION };
 
     if ((objc != 3) && (objc != 4)) {
 	Tcl_WrongNumArgs(interp, 1, objv, "channelId event ?script?");
@@ -8945,7 +8945,7 @@ Tcl_FileEventObjCmd(
     }
     chanPtr = (Channel *) chan;
     statePtr = chanPtr->state;
-    if ((statePtr->flags & mask) == 0) {
+    if ( ((statePtr->flags | TCL_EXCEPTION) & mask) == 0) {
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf("channel is not %s",
 		(mask == TCL_READABLE) ? "readable" : "writable"));
 	return TCL_ERROR;

tests/chanio.test

@@ -5498,7 +5498,7 @@ test chan-io-41.4 {Tcl_FileeventCmd: errors} -constraints fileevent -body {
 } -returnCodes error -result {can not find channel named "gorp"}
 test chan-io-41.5 {Tcl_FileeventCmd: errors} -constraints fileevent -body {
     chan event gorp who-knows
-} -returnCodes error -result {bad event name "who-knows": must be readable or writable}
+} -returnCodes error -result {bad event name "who-knows": must be readable, writable, or exception}
 
 #
 # Test chan event on a file

tests/io.test

@@ -5797,7 +5797,7 @@ test io-41.4 {Tcl_FileeventCmd: errors} {fileevent} {
 } {1 {can not find channel named "gorp"}}
 test io-41.5 {Tcl_FileeventCmd: errors} {fileevent} {
     list [catch {fileevent gorp who-knows} msg] $msg
-} {1 {bad event name "who-knows": must be readable or writable}}
+} {1 {bad event name "who-knows": must be readable, writable, or exception}}
 
 #
 # Test fileevent on a file

tests/zlib.test

@@ -840,7 +840,7 @@ test zlib-10.0 "bug #2818131 (close with null interp)" -constraints {
     close $srv
     rename bgerror {}
 } -returnCodes error \
-  -result {bad event name "xyzzy": must be readable or writable}
+  -result {bad event name "xyzzy": must be readable, writable, or exception}
 test zlib-10.1 "bug #2818131 (mismatch read)" -constraints {
     zlib
 } -setup {

unix/tclEpollNotfy.c

@@ -221,7 +221,10 @@ PlatformEventsControl(
     struct stat fdStat;
 
     newEvent.events = 0;
-    if (filePtr->mask & (TCL_READABLE | TCL_EXCEPTION)) {
+    if (filePtr->mask & TCL_EXCEPTION) {
+	newEvent.events |= EPOLLERR | EPOLLPRI;
+    }
+    if (filePtr->mask & TCL_READABLE) {
 	newEvent.events |= EPOLLIN;
     }
     if (filePtr->mask & TCL_WRITABLE) {
@@ -242,7 +245,9 @@ PlatformEventsControl(
      *		associated with regular files belonging to tsdPtr.
      */
 
-    if (fstat(filePtr->fd, &fdStat) == -1) {
+    if (newEvent.events & EPOLLERR) {
+	/* if exceptions are requested, ignore file type */
+    } else if (fstat(filePtr->fd, &fdStat) == -1) {
 	Tcl_Panic("fstat: %s", strerror(errno));
     } else if ((fdStat.st_mode & S_IFMT) == S_IFREG) {
 	switch (op) {
@@ -256,7 +261,8 @@ PlatformEventsControl(
 	    break;
 	}
 	return;
-   } else if (epoll_ctl(tsdPtr->eventsFd, op, filePtr->fd, &newEvent) == -1) {
+   }
+   if (epoll_ctl(tsdPtr->eventsFd, op, filePtr->fd, &newEvent) == -1) {
 	Tcl_Panic("epoll_ctl: %s", strerror(errno));
    }
 }