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From: "Houder" <houder@xs4all.nl>
To: cygwin@cygwin.com, "Thomas Wolff" <towo@towo.net>
Subject: Re: [ANNOUNCEMENT] Update: mintty 2.1.2
Date: Mon, 27 Jul 2015 10:54:00 -0000	[thread overview]
Message-ID: <994a85838723f326327975650e214a79.squirrel@oude-webmail.xs4all.nl> (raw)
In-Reply-To: <4afa07869c07cd6a57441b221ca5fdf7.squirrel@oude-webmail.xs4all.nl>

> Hi Thomas,
>
> Let me rephrase/summarize my findings:
>
> Executing 'mintty -D' (i.e. v212)
>
>     from a shortcut to bash (i.e. Cygwin console),
>
> will fork itself, where the child will turn itself into a session leader, as
> desired.
>
> i.e. the following code will be executed:
>
> #if 1 // Thomas
>  if (daemonize && !isatty(0)) { // daemonize == true, !isatty(0) == true
>    if (fork() > 0) exit(0);
>    setsid(); // executed by child
>  }
> #endif
>
> 1. if 'Windows Basic' has been selected (Personalization), the child will crash.
>
> 2. if 'Windows 7' has been selected (Personalization), the child will NOT crash,
>    ... and, eventually, fork itself, where the "grandchild" will replace itself
>    by bash in the end.

Hi Thomas,

I _may_ have found the cause of the problem ... (but all bets are off!).

main() in winmain.c starts as follows:

int
main(int argc, char *argv[])
{
  main_argv = argv;
  main_argc = argc;
// Henri: too early?
#if 0
  load_dwm_funcs();
#endif

load_dwm_funcs() apparently "loads" a library, as follows:

load_dwm_funcs
  load_sys_library("dwmapi.dll")
    LoadLibrary ...

Will the library still be loaded in the child, I asked myself ...

As an experiment, I moved the call to load_dwm_funcs() after fork/setsid.

... fork()
... setsid()

// child continues ...

// Henri: will dwmapi.dll still be loaded after the fork() call ?????
#if 1
load_dwm_funcs();
#endif

Still more testing is needed ... but I _may_ have found why mintty -D crashes. But
I cannot explain why the crash does not occur when "eye candy" has been enabled.

Henri


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  reply	other threads:[~2015-07-27 10:54 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-07-23 22:41 Thomas Wolff
2015-07-24  7:50 ` Houder
2015-07-24 11:40   ` Thomas Wolff
2015-07-24 13:18     ` Houder
2015-07-24 13:25       ` Houder
2015-07-24 13:34       ` Corinna Vinschen
2015-07-24 22:03       ` Thomas Wolff
2015-07-25 17:03         ` Houder
2015-07-25 20:15           ` Houder
2015-07-26 11:09             ` Houder
2015-07-26 11:58               ` Houder
2015-07-26 16:53                 ` Thomas Wolff
2015-07-26 22:59                   ` Houder
2015-07-27 10:54                     ` Houder [this message]
2015-07-27 15:58                       ` Houder
2015-07-27 17:44                         ` Thomas Wolff
2015-07-27 19:29                           ` Corinna Vinschen
2015-07-27 20:44                             ` Houder
2015-07-27 20:58                               ` Houder
2015-07-27 20:59                               ` Corinna Vinschen
2015-07-27 21:14                                 ` Houder
2015-07-27  7:17             ` Csaba Raduly
2015-07-27  8:50               ` Houder
2015-07-24 13:25     ` Corinna Vinschen
2015-07-27 18:08 ` Buchbinder, Barry (NIH/NIAID) [E]
2015-07-27 22:01   ` Thomas Wolff
2015-07-30 12:00 ` Kptain

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