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Ted Mielczarek luser

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luser /
Created Jan 14, 2021
Illustration of a potential issue with subprocesses in Go

I ran into this issue at work in a test runner we have that is written in Go and runs a test suite which is a node module, which itself spawns several subprocesses. The issue was that one of the subprocesses inherited its parents' stdout file descriptor, but would outlive the parent process being killed. If you use Go's exec.Cmd to run a process and set its Stdout or Stderr to something that is not a File, a goroutine will be spawned to drive that I/O when calling Cmd.Start, and all such goroutines will be run to completion as part of Cmd.Wait. In this situation, because the grandchild process stays alive, it keeps the stdout pipe open, thus Cmd.Wait blocks until it exits.

subprocess.go is a minimal testcase to display the issue. It spawns itself as a child process with piped stdout, then waits one second before killing the subprocess and waiting on it. The child process spawns itself as a grandchild with inherited stdout and sleeps for 5 seconds before exiting. The grandchild process simply

use std::char::{decode_utf16, DecodeUtf16Error};
pub struct wstr([u16]);
impl wstr {
pub fn to_wstring(&self) -> WString {
View compile error
In file included from /build/mcpelauncher/fake-jni/examples/src/main.cpp:3:
In file included from /build/mcpelauncher/fake-jni/include/fake-jni/jvm.h:5:
/build/mcpelauncher/fake-jni/include/fake-jni/internal/meta/field.h:61:73: error: conversion from 'FakeJni::JString' to 'jvalue' is ambiguous
((T*)inst)->*((type_t)field) = ValueTranslator<F>::convert_set(env, *((F*)value));
/build/mcpelauncher/fake-jni/include/fake-jni/jvm.h:1465:59: note: in instantiation of member function 'FakeJni::_CX::FieldAccessor<FakeJni::JString ExampleClass::*>::set' requested here
proxySetFunc((void (*)())&_CX::FieldAccessor<T (M::*)>::set),
/build/mcpelauncher/fake-jni/include/fake-jni/jvm.h:1386:38: note: in instantiation of function template specialization 'FakeJni::JFieldID::JFieldID<FakeJni::JString, ExampleClass>' requested here
return clazz->registerField(new JFieldID(fie
This file has been truncated, but you can view the full file.
use std::prelude::v1::*;
extern crate std;
pub use bevy_hecs::{Query as HecsQuery, *};
mod resource {
luser /
Created Apr 29, 2020
/// Create a `Future` that will resolve after `idle_period` has elapsed, along with an `IdleReset` that can be used to reset the time period or cancel the timeout.
/// This can be used to trigger an event that should happen after a period of inactivity. Activity in this situation is indicated by calling
/// `idle_reset` on the returned `IdleReset`. The timeout can be cancelled by calling `cancel` on the `IdleReset`.
/// Returns a tuple of (`IdleReset`, `Future`)
pub fn idle_timeout_reset(
idle_period: Duration,
) -> (IdleReset, impl Future<Output = bool> + Send + 'static) {
// ...
View moco-group-april-2007.exif
ExifTool Version Number : 11.65
File Name : moco-group-april-2007.jpg
Directory : /mnt/photos
File Size : 3.0 MB
File Modification Date/Time : 2008:02:21 08:50:50-05:00
File Access Date/Time : 2008:02:21 08:50:50-05:00
File Inode Change Date/Time : 2008:02:21 08:50:50-05:00
File Permissions : rwxr-xr-x
File Type : JPEG
File Type Extension : jpg
# Filename :
# Authors : Georg Muntingh and Bjorn Lindeijer
# Version : 1.2
# Date : June 16, 2010
# Copyright : Public Domain
import os, sys, networkx
from PIL import Image
class TileMap:

Firefox committers touching Rust code

  1. Clone the mozilla-central Mercurial repository:

    hg clone

  2. Clone the version-control-tools repository:

    hg clone

  3. Enable the mozext and firefoxtree extensions in .hgrc:


Sample sccache logs

These are logs from using sccache as a compiler wrapper to build this simple Rust crate.

sccache-env-logger.log was produced from the master branch of sccache, while sccache-tokio-trace.log was produced from the tokio-trace branch.

The logs were produced by running these commands:

git clone
View sccache-env-logger-plain.log
TRACE 2019-02-26T13:56:45Z: sccache::cmdline: parse
DEBUG 2019-02-26T13:56:45Z: sccache::config: Attempting to read config file at "/Users/luser/Library/Preferences/Mozilla.sccache/config"
DEBUG 2019-02-26T13:56:45Z: sccache::config: Couldn't open config file: No such file or directory (os error 2)
TRACE 2019-02-26T13:56:45Z: sccache::commands: Command::InternalStartServer
INFO 2019-02-26T13:56:45Z: sccache::server: start_server: port: 4226
INFO 2019-02-26T13:56:45Z: sccache::cache::cache: No configured caches successful, falling back to default
TRACE 2019-02-26T13:56:45Z: sccache::cache::cache: Using DiskCache("/Users/luser/Library/Caches/Mozilla.sccache", 10737418240)
INFO 2019-02-26T13:56:45Z: sccache::server: server started, listening on port 4226
TRACE 2019-02-26T13:56:51Z: sccache::server: incoming connection
TRACE 2019-02-26T13:56:51Z: sccache::server: handle_client