Generate Core Dump File C++ on Ubuntu 20.04

setup

cat /proc/sys/kernel/core_pattern
|/usr/share/apport/apport -p%p -s%s -c%c -d%d -P%P -u%u -g%g -- %E
$ ulimit -c
0
$ ulimit -c unlimited
0
$ ulimit -c
unlimited

setup
sudo sysctl kernel.core_pattern=/var/crash/core.%c.%d.%p.%t.%s.%E
cat /proc/sys/kernel/core_pattern
/var/crash/%E.%p.%t.%s

code

touch a.cpp
nano

int main() {
int a = 1/0;
int b = a+1;
return 0;
}

g++ a.cpp
./a.out
Floating point exception (core dumped)

dump

ll /var/crash/
core.18446744073709551615.1.30876.1671522014.8.!home!user!a.out

 

No use

ll /var/lib/apport/coredump
sudo sysctl kernel.core_pattern=core.%p.%s.%c.%d.%P

Reference

https://askubuntu.com/questions/440708/unable-to-generate-core-dump-after-apport-disable

docker with postgres:14.3

https://medium.com/alberthg-docker-notes/docker%E7%AD%86%E8%A8%98-%E9%80%B2%E5%85%A5container-%E5%BB%BA%E7%AB%8B%E4%B8%A6%E6%93%8D%E4%BD%9C-postgresql-container-d221ba39aaec

docker pull postgres:14.3

docker create --name my-postgres -p 8080:5432 -e POSTGRES_PASSWORD=admin postgres:14.3

docker start my-postgres

docker exec my-postgres psql --help

docker exec my-postgres psql -V

docker exec my-postgres psql -U postgres -l

docker exec -it my-postgres psql -U postgres

\q

docker exec -it my-postgres bash

apt-getupdate

apt-get install net-tools

172.17.0.2

docker exec -it my-postgres psql -U postgres -c "create role <user-name> with login password '<password>';"

docker from scratch

 https://www.runoob.com/docker/docker-container-usage.html

Windows 11, Install docker Desktop, choose WSL2 not HyperV

docker run -itd -P --name banana ubuntu /bin/bash  # -d detached, -P all ports
docker exec -it banana ubuntu /bin/bash  # interactive, terminal
apt-get install curl  # this may cause Unable to locate package curl
apt-get update # then can install
apt-get install curl
apt-get install ssh
service ssh start
systemctl enable enable ssh
service ssh status
apt-get install net-tools
apt-get install netcat
apt-get install iputils-ping
ping 172.17.0.1  # this is the host
apt-get install telnet
telnet 172.17.0.1 8000

docker ps -a  # active

docker stop banana
docker commit banana banana02
docker run -itd -p 5432:5000 --name banana02 banana02 /bin/bash
docker exec -it banana02 /bin/bash
python3 -m http.server 5000
On host, firefox http://127.0.0.1:5432
On banana02, see 172.17.0.1 GET / 200

docker images

1、从已经创建的容器中更新镜像，并且提交这个镜像 (commit)

docker run -itd --name banana02 ubuntu:22.04 /bin/bash
docker exec -it banana02 /bin/bash
apt-get update
apt-get install -y iputils-ping netcat telnet
docker commit -m="John first commit" -a="John Doe author" banana02 ubuntu:v1
docker run -itd -P --name banana03 ubuntu:v1 /bin/bash
docker exec -it banana03 /bin/bash
nc -l 5000
On host, telnet 127.0.0.1 49154

2、使用 Dockerfile 指令来创建一个新的镜像 (Dockerfile)

cat Dockerfile
FROM    ubuntu:22.04
MAINTAINER      Fisher "fisher@sudops.com"
RUN     apt-get -y update
RUN     apt-get install -y iputils-ping netcat telnet
EXPOSE  22
EXPOSE  80
EXPOSE  5000

docker build -t ubuntu:v2 .
docker run -itd -p 5000:5000 -P --name banana04 ubuntu:v2 /bin/bash
docker exec -it banana04 /bin/bash
49159:22
5000:5000
49158:80
docker tag ubuntu:v2 ubuntu:v3

End

GDB with a crash file and usual commands (and also CLion)

The crash file could be just 10MB

Commands

sudo apport-unpack some.10MB.crash CoreDump

sudo chown -R user:user CoreDump/

cd ./CoreDump

gdb ./binary CoreDump

Commands

frame

up

down

bt

list

info locals

info args

print iter

print hashTable

CLion

Run > Open Core Dump

Core dump: The 200MB core dump file

Symbol file: The originating executable file