[clang] [wip][Clang-Repl] Add custom function as lambda in launchExecutor and fetch PID of launched executor (PR #147478)

[Vipul Cariappa via cfe-commits]

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@@ -91,7 +95,8 @@ createSharedMemoryManager(SimpleRemoteEPC &SREPC,
 
 Expected<std::unique_ptr<SimpleRemoteEPC>>
 launchExecutor(StringRef ExecutablePath, bool UseSharedMemory,
-               llvm::StringRef SlabAllocateSizeString) {
+               llvm::StringRef SlabAllocateSizeString,
+               std::function<void()> CustomizeFork) {
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Vipul-Cariappa wrote:

I would say the current design is better. Because the lambda actually does not need to do anything by default.
We only need redirections for xeus-cpp, and xeus-cpp can set the lambda to do that.

https://github.com/llvm/llvm-project/pull/147478