Add `ChildExt::kill_process_group` by jmillikin · Pull Request #156539 · rust-lang/rust

jmillikin · 2026-05-13T11:00:16Z

ACP: rust-lang/libs-team#791
Tracking issue: #156537

This function wraps POSIX `killpg()`, and on Linux additionally may be implemented by `pidfd_send_signal`.

rustbot · 2026-05-13T11:00:22Z

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rustbot · 2026-05-13T12:37:44Z

Reminder, once the PR becomes ready for a review, use @rustbot ready.

This function wraps POSIX `killpg(pid, SIGKILL)`, and on Linux additionally may be implemented by `pidfd_send_signal`.

jmillikin · 2026-05-13T13:40:35Z

@rustbot ready

nia-e · 2026-05-13T14:34:16Z

@bors r+ rollup

rust-bors · 2026-05-13T14:34:20Z

📌 Commit 7bf5fe7 has been approved by nia-e

It is now in the queue for this repository.

🌲 The tree is currently closed for pull requests below priority 1. This pull request will be tested once the tree is reopened.

…nia-e Add `ChildExt::kill_process_group` ACP: rust-lang/libs-team#791 Tracking issue: rust-lang#156537

…uwer Rollup of 5 pull requests Successful merges: - #155521 (Add lint againts invalid runtime symbol definitions) - #156500 (Privacy: move macros handling to early stage) - #156413 (rustdoc: Correctness & perf improvements to link-to-definition) - #156539 (Add `ChildExt::kill_process_group`) - #156540 (use `deref_patterns` in `rustdoc` instead of `box_patterns`)

…nia-e Add `ChildExt::kill_process_group` ACP: rust-lang/libs-team#791 Tracking issue: rust-lang#156537

…uwer Rollup of 7 pull requests Successful merges: - #156552 (Clippy subtree update) - #156344 (Do not index past end of buffer when checking heuristic in error index syntax highlighter) - #156500 (Privacy: move macros handling to early stage) - #156260 (test: suppress deprecation warning) - #156413 (rustdoc: Correctness & perf improvements to link-to-definition) - #156539 (Add `ChildExt::kill_process_group`) - #156540 (use `deref_patterns` in `rustdoc` instead of `box_patterns`)

Rollup merge of #156539 - jmillikin:unix-childext-killpg, r=nia-e Add `ChildExt::kill_process_group` ACP: rust-lang/libs-team#791 Tracking issue: #156537

VxWorks has no process groups: the SDK defines no `killpg`, and `getpgrp`/`setpgid` are no-ops in libunix, so `kill(-pgrp, sig)` is no substitute either. libc cannot usefully declare `killpg` for this target, so the call added in rust-lang#156539 leaves the target unable to build std. Return `ErrorKind::Unsupported` instead, as the `unsupported` backend does and as `kill_process_group` already does for espidf.

…upported, r=Darksonn std: make send_process_group_signal unsupported on VxWorks `x86_64-wrs-vxworks` doesn't build std: `cargo new` plus `-Zbuild-std` stops with E0425 on `libc::killpg`, which rust-lang#156539 introduced. libc has never declared `killpg` for vxworks, and declaring it wouldn't help. On wrsdk-vxworks7-qemu-1.17.0 there's no `killpg` in the headers, the sysroot archives or the prebuilt kernel, and `getpgrp`/`setpgid` are no-ops in libunix: `getpgrp` returns a constant 0, `setpgid` stores nothing. That rules out `kill(-pgrp, sig)` too. `Command::process_group` is already ignored on this target, since `get_pgroup` is only read by the fork/posix_spawn path while vxworks spawns through `rtpSpawn`. Closes rust-lang#159969.

Rollup merge of #159991 - physwkim:vxworks-process-group-unsupported, r=Darksonn std: make send_process_group_signal unsupported on VxWorks `x86_64-wrs-vxworks` doesn't build std: `cargo new` plus `-Zbuild-std` stops with E0425 on `libc::killpg`, which #156539 introduced. libc has never declared `killpg` for vxworks, and declaring it wouldn't help. On wrsdk-vxworks7-qemu-1.17.0 there's no `killpg` in the headers, the sysroot archives or the prebuilt kernel, and `getpgrp`/`setpgid` are no-ops in libunix: `getpgrp` returns a constant 0, `setpgid` stores nothing. That rules out `kill(-pgrp, sig)` too. `Command::process_group` is already ignored on this target, since `get_pgroup` is only read by the fork/posix_spawn path while vxworks spawns through `rtpSpawn`. Closes #159969.

… r=Darksonn std: make send_process_group_signal unsupported on VxWorks `x86_64-wrs-vxworks` doesn't build std: `cargo new` plus `-Zbuild-std` stops with E0425 on `libc::killpg`, which rust-lang/rust#156539 introduced. libc has never declared `killpg` for vxworks, and declaring it wouldn't help. On wrsdk-vxworks7-qemu-1.17.0 there's no `killpg` in the headers, the sysroot archives or the prebuilt kernel, and `getpgrp`/`setpgid` are no-ops in libunix: `getpgrp` returns a constant 0, `setpgid` stores nothing. That rules out `kill(-pgrp, sig)` too. `Command::process_group` is already ignored on this target, since `get_pgroup` is only read by the fork/posix_spawn path while vxworks spawns through `rtpSpawn`. Closes rust-lang/rust#159969.

…uwer Rollup of 7 pull requests Successful merges: - rust-lang/rust#156552 (Clippy subtree update) - rust-lang/rust#156344 (Do not index past end of buffer when checking heuristic in error index syntax highlighter) - rust-lang/rust#156500 (Privacy: move macros handling to early stage) - rust-lang/rust#156260 (test: suppress deprecation warning) - rust-lang/rust#156413 (rustdoc: Correctness & perf improvements to link-to-definition) - rust-lang/rust#156539 (Add `ChildExt::kill_process_group`) - rust-lang/rust#156540 (use `deref_patterns` in `rustdoc` instead of `box_patterns`)

tgross35 · 2026-09-29T04:36:12Z

+    ///
+    /// [`Child::kill`]: process::Child::kill
+    #[unstable(feature = "unix_kill_process_group", issue = "156537")]
+    fn kill_process_group(&mut self) -> io::Result<()>;


Why was &mut used here but not for send_process_group_signal when they use the same call internally?

worth bringing up on the tracking issue - i just ensured this matched the ACP, but that was approved separately. good catch!

It's &mut to match Child::kill

Huh: kill and wait take &mut self but don't strictly need to. I suppose it may account for targets that need to do more?

Maybe all our signal sending functions should be &mut to be safe. I'll nominate #141975.

Add send_process_group_signal to existing unix_send_signal feature

2c30279

This function wraps POSIX `killpg()`, and on Linux additionally may be implemented by `pidfd_send_signal`.

rustbot assigned nia-e May 13, 2026

rustbot added O-unix Operating system: Unix-like S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-libs Relevant to the library team, which will review and decide on the PR/issue. labels May 13, 2026

nia-e requested changes May 13, 2026

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Comment thread library/std/src/os/unix/process.rs

Comment thread library/std/src/os/unix/process.rs Outdated

Comment thread library/std/src/os/unix/process.rs

rustbot added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels May 13, 2026

Add ChildExt::kill_process_group

7bf5fe7

This function wraps POSIX `killpg(pid, SIGKILL)`, and on Linux additionally may be implemented by `pidfd_send_signal`.

jmillikin force-pushed the unix-childext-killpg branch from 3d3f33e to 7bf5fe7 Compare May 13, 2026 13:40

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels May 13, 2026

rust-bors Bot added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels May 13, 2026

JonathanBrouwer added a commit to JonathanBrouwer/rust that referenced this pull request May 13, 2026

Rollup merge of rust-lang#156539 - jmillikin:unix-childext-killpg, r=…

654c95a

…nia-e Add `ChildExt::kill_process_group` ACP: rust-lang/libs-team#791 Tracking issue: rust-lang#156537

JonathanBrouwer mentioned this pull request May 13, 2026

Rollup of 5 pull requests #156553

Closed

JonathanBrouwer added a commit to JonathanBrouwer/rust that referenced this pull request May 13, 2026

Rollup merge of rust-lang#156539 - jmillikin:unix-childext-killpg, r=…

1120101

…nia-e Add `ChildExt::kill_process_group` ACP: rust-lang/libs-team#791 Tracking issue: rust-lang#156537

This was referenced May 13, 2026

Rollup of 6 pull requests #156555

Closed

Rollup of 7 pull requests #156559

Merged

rust-bors Bot merged commit 6ed8760 into rust-lang:main May 14, 2026
11 checks passed

rustbot added this to the 1.97.0 milestone May 14, 2026

rust-timer added a commit that referenced this pull request May 14, 2026

Unrolled build for #156539

ceadb6a

Rollup merge of #156539 - jmillikin:unix-childext-killpg, r=nia-e Add `ChildExt::kill_process_group` ACP: rust-lang/libs-team#791 Tracking issue: #156537

jmillikin deleted the unix-childext-killpg branch May 14, 2026 11:42

jmillikin mentioned this pull request May 14, 2026

Tracking Issue for unix_send_signal #141975

Open

4 of 9 tasks

folkertdev mentioned this pull request Jun 2, 2026

Tracking Issue for unix_kill_process_group #156537

Open

5 tasks

workingjubilee mentioned this pull request Jul 26, 2026

std calls libc::killpg on VxWorks, which neither libc nor the platform provides #159969

Closed

physwkim mentioned this pull request Jul 27, 2026

std: make send_process_group_signal unsupported on VxWorks #159991

Merged

tgross35 reviewed Sep 29, 2026

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Add `ChildExt::kill_process_group` - #156539

Add `ChildExt::kill_process_group`#156539
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