From Newsgroup: comp.lang.tcl

I experience a Tcl crash under Windows 11 for almost every simple error.

A variable is not defined: Crash
A procedure is not defined: Crash
A namespace is not defined: Crash

By "Crash" I mean the program exits, closes.

Why is this happening?
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From Newsgroup: comp.lang.tcl

Am 07.09.2025 um 20:56 schrieb meshparts:

I experience a Tcl crash under Windows 11 for almost every simple error.

A variable is not defined: Crash
A procedure is not defined: Crash
A namespace is not defined: Crash

By "Crash" I mean the program exits, closes.

Why is this happening?

I have no such experience. My application only exits on the exit command.

Sorry,
Harald
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From Newsgroup: comp.lang.tcl

Am 07.09.2025 um 21:17 schrieb Harald Oehlmann:

Am 07.09.2025 um 20:56 schrieb meshparts:

I experience a Tcl crash under Windows 11 for almost every simple error.

A variable is not defined: Crash
A procedure is not defined: Crash
A namespace is not defined: Crash

By "Crash" I mean the program exits, closes.

Why is this happening?

I have no such experience. My application only exits on the exit command.

Sorry,
Harald

After long searching, I found out the reason for the crash.
I have a baground error handler (bgerror) that not only writes the error information to a file but also creates a system notification, as
supported by Tcl 9.

This seems to crash the Tcl/Tk app in most of the cases.
I suppose there are some things that are not allowed in a system
notification message.

Here is the last example that causes the crash:

tk sysnotify Warning {*** START OF ERROR MESSAGE ***
bad index "": must be integer?[+-]integer? or end?[+-]integer?
*** ERROR INFO ***
bad index "": must be integer?[+-]integer? or end?[+-]integer?
while executing
"lsearch -nocase -start $start $values $value*"
(procedure "::ttk::combobox::CompleteEntry" line 33)
invoked from within
"::ttk::combobox::CompleteEntry .fkm.sw.sf.mf.cf.f3.e5 1 "
(command bound to event)
*** ERROR STACK ***
INNER:invokeStk1 lsearch -nocase -start {} {0 16 32 100 150 300} 1* CALL:::ttk::combobox::CompleteEntry .fkm.sw.sf.mf.cf.f3.e5 1

*** END OF ERROR MESSAGE ***}

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From Newsgroup: comp.lang.tcl

* meshparts <[email protected]>
| Here is the last example that causes the crash:

| tk sysnotify Warning {*** START OF ERROR MESSAGE ***

https://www.tcl-lang.org/man/tcl9.0/TkCmd/sysnotify.html

PLATFORM NOTES
Windows
The image is taken from the system tray, i.e., sysnotify can only be
called when a systray was installed.

I have no idea what a systray is, but did you install one?

https://www.tcl-lang.org/man/tcl9.0/TkCmd/systray.html

Agreed, Tk should not crash, but if the invocation of the error handler
raises an error which calls the error handler which raises an error
which [repeat ad inf]...

R'
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From Newsgroup: comp.lang.tcl

Am 08.09.2025 um 16:59 schrieb meshparts:

Am 07.09.2025 um 21:17 schrieb Harald Oehlmann:

Am 07.09.2025 um 20:56 schrieb meshparts:

I experience a Tcl crash under Windows 11 for almost every simple error. >>>
A variable is not defined: Crash
A procedure is not defined: Crash
A namespace is not defined: Crash

By "Crash" I mean the program exits, closes.

Why is this happening?

I have no such experience. My application only exits on the exit command.

Sorry,
Harald

After long searching, I found out the reason for the crash.
I have a baground error handler (bgerror) that not only writes the error information to a file but also creates a system notification, as
supported by Tcl 9.

This seems to crash the Tcl/Tk app in most of the cases.
I suppose there are some things that are not allowed in a system notification message.

Here is the last example that causes the crash:

tk sysnotify Warning {*** START OF ERROR MESSAGE ***
bad index "": must be integer?[+-]integer? or end?[+-]integer?
*** ERROR INFO ***
bad index "": must be integer?[+-]integer? or end?[+-]integer?
    while executing
"lsearch -nocase -start $start $values $value*"
    (procedure "::ttk::combobox::CompleteEntry" line 33)
    invoked from within
"::ttk::combobox::CompleteEntry .fkm.sw.sf.mf.cf.f3.e5 1 "
    (command bound to event)
*** ERROR STACK ***
INNER:invokeStk1

CALL:::ttk::combobox::CompleteEntry .fkm.sw.sf.mf.cf.f3.e5 1

*** END OF ERROR MESSAGE ***}

lsearch -nocase -start {} {0 16 32 100 150 300} 1*

It says: the argument of "-start" may not be the empty string.
Unfortunately, it is. This is the index reform. See migration notes.

Take care,
Harald
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From Newsgroup: comp.lang.tcl

Am 08.09.2025 um 19:53 schrieb Ralf Fassel:

* meshparts <[email protected]>
| Here is the last example that causes the crash:

| tk sysnotify Warning {*** START OF ERROR MESSAGE ***

https://www.tcl-lang.org/man/tcl9.0/TkCmd/sysnotify.html

PLATFORM NOTES
Windows
The image is taken from the system tray, i.e., sysnotify can only be
called when a systray was installed.

I have no idea what a systray is, but did you install one?

https://www.tcl-lang.org/man/tcl9.0/TkCmd/systray.html

Agreed, Tk should not crash, but if the invocation of the error handler raises an error which calls the error handler which raises an error
which [repeat ad inf]...

R'

System tray is kind of general concept. In Windows it's placed on the
task bar as a series of icons.

Tcl 9 introduces for the first time an interface to the system try
(which is awesome).

So no, I don't need to install anything, it's standard.

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From Newsgroup: comp.lang.tcl

Am 08.09.2025 um 21:16 schrieb Harald Oehlmann:

Am 08.09.2025 um 16:59 schrieb meshparts:

Am 07.09.2025 um 21:17 schrieb Harald Oehlmann:

Am 07.09.2025 um 20:56 schrieb meshparts:

I experience a Tcl crash under Windows 11 for almost every simple
error.

A variable is not defined: Crash
A procedure is not defined: Crash
A namespace is not defined: Crash

By "Crash" I mean the program exits, closes.

Why is this happening?

I have no such experience. My application only exits on the exit
command.

Sorry,
Harald

After long searching, I found out the reason for the crash.
I have a baground error handler (bgerror) that not only writes the
error information to a file but also creates a system notification, as
supported by Tcl 9.

This seems to crash the Tcl/Tk app in most of the cases.
I suppose there are some things that are not allowed in a system
notification message.

Here is the last example that causes the crash:

tk sysnotify Warning {*** START OF ERROR MESSAGE ***
bad index "": must be integer?[+-]integer? or end?[+-]integer?
*** ERROR INFO ***
bad index "": must be integer?[+-]integer? or end?[+-]integer?
     while executing
"lsearch -nocase -start $start $values $value*"
     (procedure "::ttk::combobox::CompleteEntry" line 33)
     invoked from within
"::ttk::combobox::CompleteEntry .fkm.sw.sf.mf.cf.f3.e5 1 "
     (command bound to event)
*** ERROR STACK ***
INNER:invokeStk1

CALL:::ttk::combobox::CompleteEntry .fkm.sw.sf.mf.cf.f3.e5 1

*** END OF ERROR MESSAGE ***}

lsearch -nocase -start {} {0 16 32 100 150 300} 1*

It says: the argument of "-start" may not be the empty string.
Unfortunately, it is. This is the index reform. See migration notes.

Take care,
Harald

If I understand you right, you are exlaining the cause of the error, but
this is not the point here.

I get an error and by background error handler outputs the error trace.

The thing is, that Tcl crashes when I write the error trace to the
system tray. There is something in that message string that causes the
crash.
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From Newsgroup: comp.lang.tcl

On 9/8/25 21:54, meshparts wrote:

…
The thing is, that Tcl crashes when I write the error trace to the
system tray. There is something in that message string that causes the crash.

Most likely you found overwritten memory which deserves a ticket in
the Tk repo. I believe that I have a POC fix here

https://androwish.org/home/info/09ee4092e874d3a5

but better let the Tk and Win32 experts work on this problem.

HTH,
Christian
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