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How to use gdb in Ubuntu Terminal

Here's a practical, minimal guide for using GDB in Ubuntu terminal — from launching to setting breakpoints and navigating your code. 🧰 Step 1: Compile with Debug Symbols Use -g and disable optimizations ( -O0 preferred for debugging): bash Copy Edit g++ -g -O0 -o myprog myprog.cpp 🚀 Step 2: Launch GDB bash Copy Edit gdb ./myprog You'll see a (gdb) prompt. 🎯 Step 3: Set Breakpoints You can set breakpoints in three main ways : ✅ a. At a function gdb Copy Edit (gdb) break main ✅ b. At a specific file and line gdb Copy Edit (gdb) break myprog.cpp:42 ✅ c. At a method in a class gdb Copy Edit (gdb) break MyClass::doSomething If the symbol is mangled (C++), GDB usually demangles automatically, especially if compiled with -g . ▶️ Step 4: Run the Program gdb Copy Edit (gdb) run 🧭 Step 5: Navigate Command Meaning next or n Step over current line step or s Step into function call finish Run until current function returns continue or c Continue until...

Uninstall Postgresql completely from ubuntu 24

You said:

uninstall postgres completely from ubuntu
ChatGPT said:
ChatGPT

To completely uninstall PostgreSQL from your Ubuntu system, including removing all associated data and configuration files, follow these steps:

1. Stop PostgreSQL Service

First, stop any running PostgreSQL services before uninstalling.

bash
sudo systemctl stop postgresql

2. Remove PostgreSQL Packages

Use apt to remove PostgreSQL packages, including client libraries and server binaries.

bash
sudo apt-get --purge remove postgresql postgresql-* libpq-dev

The --purge option ensures that configuration files are also removed.

3. Remove PostgreSQL Data Directory

PostgreSQL data (such as databases and logs) is stored in /var/lib/postgresql by default. Remove this directory to delete all databases and related data.

bash
sudo rm -rf /var/lib/postgresql/

4. Remove PostgreSQL Configuration Files

PostgreSQL configuration files are stored in /etc/postgresql. Remove this directory to delete all configuration files.

bash
sudo rm -rf /etc/postgresql/

5. Remove PostgreSQL User and Group

PostgreSQL creates a system user and group named postgres. You can remove them using the following commands:

bash
sudo deluser postgres sudo delgroup postgres

6. Clean Up Dependencies

Use apt-get autoremove to remove any leftover dependencies that were installed with PostgreSQL but are no longer needed.

bash
sudo apt-get autoremove

7. Remove PostgreSQL Logs

PostgreSQL logs are typically stored in /var/log/postgresql. Remove this directory to delete any remaining log files.

bash
sudo rm -rf /var/log/postgresql/

8. Verify Uninstallation

Ensure that PostgreSQL has been fully removed by checking if the psql command still exists:

bash
psql --version

If it returns psql: command not found, PostgreSQL has been successfully removed.

By following these steps, you will have completely uninstalled PostgreSQL and removed all related files from your Ubuntu system.

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