Re: [PATCH 1/5] Cygwin: Make 'ulimit -c' control writing a coredump

[Jon Turney <jon.turney@dronecode.org.uk>]

On 15/01/2024 09:46, Corinna Vinschen wrote:
> On Jan 13 14:20, Jon Turney wrote:
>> On 12/01/2024 14:09, Jon Turney wrote:
>>> +
>>> +  PWCHAR cp = dumper_command;
>>> +  cp = wcpcpy (cp, L"\"");
>>> +  cp = wcpcpy (cp, dll_dir);
>>> +  cp = wcpcpy (cp, L"\\dumper.exe");
>>> +  cp = wcpcpy (cp, L"\" ");
>>> +  cp = wcpcpy (cp, L"\"");
>>> +  cp = wcpcpy (cp, global_progname);
>>
>> I wonder if this should be program_invocation_short_name, so that the
>> coredump is created in the cwd, rather than next to the executable.
> 
> program_invocation_short_name would be nice, but does it really matter?
> 
> Because...
> 
>> But then, there's then no way to get similar behaviour if you decide you
>> want to use minidumps instead (by setting CYGWIN="error_start=minidumper"),
>> as the first argument to dumper/minidump is the full path to the program (to
>> match the 'prog procID' style of invoking gdb), but they only use it to add
>> an .core/.dmp extension to name the file to write.
>>
>> I guess that could by fixed by adding an option to the dumpers to strip
>> paths, or more control about how the JIT command is formatted.
> 
> dumper/minidumper are both called with the current working directory set
> to the ... current working directory, right?  With the full pathname as
> input, and the CWD already set the same as the dumped application, they
> can easily generate any target path for the corefile they like.
> 
> Given the actual path of the corefile can be generated by the dumpers,
> the question is how to specify where to store the corefile. For instance
> 
> - no option: CWD
> - some option -c/--coredir for anywhere else
> 
> Under Linux versions using systemd, corefiles are by default not stored
> in the CWD anymore, but to /var/lib/systemd/coredump, so there is a
> use case for arbitrary corefile paths.

Yeah, I guess an option to the dumper to control where the file is 
written is probably the best way to address this, which is something 
which can perhaps be added later...