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  • Re: after has a max?

    From Rich@21:1/5 to Gerald Lester on Mon Mar 4 21:26:49 2024
    Gerald Lester <Gerald.Lester@gmail.com> wrote:
    On 3/4/24 14:50, saitology9 wrote:
    It seems that the ms argument to the after command has a limit.  If it
    is sufficiently large, it locks up the script and you can't do anything
    until you cancel the after command.

    Further checking seems to point at "2037" or thereabouts as the critical
    time point.  Any ms argument that puts it past that point causes the
    error. But there is no info on this in the docs so perhaps it is
    something else altogether.

    % after [expr 14*365*24*60*60*1000]  puts "gui locked up?"

    First off the correct syntax would be:
    after [expr {14*365*24*60*60*1000}] {puts "gui locked up?"}


    Second off, is it realistic that the same process will be running in 14 years?

    Not really. That would be some very serious "nines" there (as in the
    supposed "5 nines" reliability of IBM mainframes).

    This is on 64-bit Windows running 32-bit tclsh.

    Thirdly, it does not seem to cause an issue on Linux (Ubuntu to be
    precise) -- so this may be a MS Windows bug.

    It sounds like 32-bit Tcl on Windows is using a 32-bit time value that
    can't represent time past the overflow point of a 32-bit time value.
    I.e., it may be suffering from the year 2038 problem:

    https://en.wikipedia.org/wiki/Year_2038_problem

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  • From Harald Oehlmann@21:1/5 to All on Tue Mar 5 08:56:15 2024
    Am 04.03.2024 um 22:29 schrieb saitology9:
    On 3/4/2024 4:26 PM, Rich wrote:

    It sounds like 32-bit Tcl on Windows is using a 32-bit time value that
    can't represent time past the overflow point of a 32-bit time value.
    I.e., it may be suffering from the year 2038 problem:

    https://en.wikipedia.org/wiki/Year_2038_problem

    I think this is it!      Thanks.

    "after" on MS-Windows also relies on the fact, that the clock is not
    changed. I have a gui written in TCL to change the clock of an embedded
    system. Then, all after events are delayed by this time.

    It may be, that all year 2038 issues with Windows are fixed in more
    recent versions of TCL. I tested it one day by advancing the clock of my machine and it worked, if I remember right.

    Take care,
    Harald

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