On Wed, 18 Nov 2020 08:41:59 GMT, Chris Plummer <cjplum...@openjdk.org> wrote:
>> Hi @plummercj ,
>>
>> Thanks for your explaination. I get your point.
>> The issue of JDK-8219721 was fixed by reverting the problematic change. And
>> the root cause of that issue is there is fixed limitation of number of
>> arguments that passing to jvm from attacher, I have figured out a way to
>> avoid touching it when adding new options to jcmd-alike tools, However this
>> PR doesn't even exceed the argument limitation, so it doesn't have chance to
>> cause the similar issue.
>>
>> BRs,
>> Lin
>
> So I assume then that the `op->arg(2)` reference will return `NULL` when an
> older `jmap` is used? Is that correct?
Hi @plummercj,
For old jmap, if "gz" option is used in commandline, it prompt usage info
indicating that option is illegal.
if "gz" option is not used, the op->arg(2) will be an empty string "",
which is set from the attacher side in the method execute() of
VirtualMachineImpl.java.
-------------
PR: https://git.openjdk.java.net/jdk/pull/1251
