The bug is here on line 121:
https://github.com/openjdk/jdk/blob/586846b84a38d285c5905437e903cfc57f609410...
If `System.out` has been closed, `fdAccess.getHandle()` will return -1. This causes `stdHandles[1]` to have the same value as if the child process's stdout was redirected with `Redirect.PIPE`. This will cause a Pipe to be created here for the child process's STDOUT on line 168:
https://github.com/openjdk/jdk/blob/586846b84a38d285c5905437e903cfc57f609410...
However, the caller of the `ProcessBuilder` is not aware of this and will not drain this pipe. This causes the child process to get stuck when writing to its stdout when the pipe 's buffer is filled up.
The fix is to treat the redirection as `Redirect.DISCARD` when `System.out` and/or `System.err` have been closed.
Ioi Lam has updated the pull request incrementally with one additional commit since the last revision: Review comments from @RogerRiggs ------------- Changes: - all: https://git.openjdk.org/jdk/pull/29198/files - new: https://git.openjdk.org/jdk/pull/29198/files/30b312e1..e9006f5e Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=29198&range=01 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=29198&range=00-01 Stats: 43 lines in 2 files changed: 9 ins; 25 del; 9 mod Patch: https://git.openjdk.org/jdk/pull/29198.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/29198/head:pull/29198 PR: https://git.openjdk.org/jdk/pull/29198