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  • PROCESS_LAUNCH_ in C stops responding when parent is killed

    From Luis Silva@21:1/5 to Bill Honaker on Sun Feb 7 20:52:58 2021
    On Monday, September 21, 2020 at 11:28:33 AM UTC-5, Bill Honaker wrote:
    On Sat, 19 Sep 2020 12:31:24 +1000, Tone <[email protected]> wrote:

    On 9/19/20 5:26 AM, Bill Honaker wrote:
    On Fri, 18 Sep 2020 11:55:50 -0700 (PDT), Luis Silva <[email protected]> wrote:

    Hi all,

    analyzing all your posts (thank you very much for all the input!!) I was able to workaround this issue. Not in an elegant way but I was able to make it work,

    I had a guardian C process PROC-A that launches another c process PROC-B which opens a tcp port and waits for I/O. If I kill, stop $PROC-A (the father) $PROC-B is still shown is status *,user but if I try to send data to it via TCP (as it is is
    function) it doesn't do anything. As if in a vegetative state.

    The workaround was:

    Instead of calling PROC-B from PROC-A (with a process launch) I call an intermediate process PROC-BYPASS via a process launch and this PROC-BYPASS calls a system(PROC-B).

    This way if PROC-A dies or any of PROC-BYPASS dies the required PROC-B is still up and running

    I know it is the least elegant way. I'll keep reading the manuals to see if I find a better way.

    Thank you all for your help


    Wolfgang made a good suggestion. Before trying to send TCP to PROC-B after PROC-A is gone,
    use PTRACE against PROC-B to find out what if anything is blocking the process. Note that the '%WT'
    value in the TACL STATUS tells you a little, but PTRACE is much more informative (sometimes).

    If nothing is blocking, then send the TCP data, and use PTRACE again.

    You may need to use the debugger against PROC-B to solve this in 'a better way'.

    Bill

    I think Bill meant PSTATE rather than PTRACE.
    Tone is correct, PSTATE is the too to use. My apologies.
    Bill

    Hi all,

    I've got this solved, whay I did was pass the prcoess nake to the child process, so it can make some sort or heartbeat.
    If the parent dies the child process finishes it current operation and exits.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From wbreidbach@21:1/5 to [email protected] on Wed Feb 10 04:09:26 2021
    [email protected] schrieb am Montag, 8. Februar 2021 um 05:52:59 UTC+1:
    On Monday, September 21, 2020 at 11:28:33 AM UTC-5, Bill Honaker wrote:
    On Sat, 19 Sep 2020 12:31:24 +1000, Tone <[email protected]> wrote:

    On 9/19/20 5:26 AM, Bill Honaker wrote:
    On Fri, 18 Sep 2020 11:55:50 -0700 (PDT), Luis Silva <[email protected]> wrote:

    Hi all,

    analyzing all your posts (thank you very much for all the input!!) I was able to workaround this issue. Not in an elegant way but I was able to make it work,

    I had a guardian C process PROC-A that launches another c process PROC-B which opens a tcp port and waits for I/O. If I kill, stop $PROC-A (the father) $PROC-B is still shown is status *,user but if I try to send data to it via TCP (as it is is
    function) it doesn't do anything. As if in a vegetative state.

    The workaround was:

    Instead of calling PROC-B from PROC-A (with a process launch) I call an intermediate process PROC-BYPASS via a process launch and this PROC-BYPASS calls a system(PROC-B).

    This way if PROC-A dies or any of PROC-BYPASS dies the required PROC-B is still up and running

    I know it is the least elegant way. I'll keep reading the manuals to see if I find a better way.

    Thank you all for your help


    Wolfgang made a good suggestion. Before trying to send TCP to PROC-B after PROC-A is gone,
    use PTRACE against PROC-B to find out what if anything is blocking the process. Note that the '%WT'
    value in the TACL STATUS tells you a little, but PTRACE is much more informative (sometimes).

    If nothing is blocking, then send the TCP data, and use PTRACE again. >>
    You may need to use the debugger against PROC-B to solve this in 'a better way'.

    Bill

    I think Bill meant PSTATE rather than PTRACE.
    Tone is correct, PSTATE is the too to use. My apologies.
    Bill
    Hi all,

    I've got this solved, whay I did was pass the prcoess nake to the child process, so it can make some sort or heartbeat.
    If the parent dies the child process finishes it current operation and exits.
    If the parent process has an OPEN on the child, the child can just check for the close-message which will be created when the parent dies. In addition you get get the info about the parent by using PROCESS_GETINFO_.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)