Question about global SegmentScope

[刘希晨]

Thank you for the clarification. I didn' mean the  SymbolLookup itself, but
the MemorySegment that MethodHandle returns, the  MethodHandle is created
by  , I already tested no matter what kind of SegmentScope SymbolLookup
used, the native MemorySegment that MethodHandle returns would always be
Global scope.

A example would be like below :

```
SymbolLookup crypto = SymbolLookup.libraryLookup(Path.of("C:\\Program Files
\\OpenSSL-Win64\\libcrypto-3-x64.dll"), SegmentScope.auto());
MemorySegment methodPointer = crypto.find("OPENSSL_version")
.orElseThrow(() -> new RuntimeException("Unable to load target native
method"));
MethodHandle openSSLVersion =
Linker.nativeLinker().downcallHandle(methodPointer,
FunctionDescriptor.of(ValueLayout.ADDRESS, ValueLayout.JAVA_INT));
MemorySegment version = (MemorySegment) openSSLVersion.invokeExact(0);
System.out.println(version);
```
the version Segment is global somehow and I don't know how to release it

Glavo <zjx001202 at gmail.com> 于2023年4月16日周日 19:38写道：

> SymbolLookup.libraryLookup takes a SegmentScope as a parameter, which
> represents the lifecycle of the returned SymbolLookup.
>
> It looks like you are using an old JDK? Panama has critical changes every
> Java update, please use the latest JDK.
>
> Glavo
>
> On Sun, Apr 16, 2023 at 6:36 PM 刘希晨 <benrush0705 at gmail.com> wrote:
>
>> Hi I have a question about global segment scope.
>>
>> If I use SymbolLookup.libraryLookup to load a C library and call its
>> function which returns a pointer , in java it's represented by a memory
>> segment, the memorysegment's scope would be global scope. Does this mean
>> that the memory segment object wouldn't be released by anything until the
>> VM exits?
>>
>
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