BUG #18671: Unable to Run PostgreSQL on EndeavourOS without Modifying visudo

The following bug has been logged on the website:

Bug reference:      18671
Logged by:          rqbin
Email address:      rq_@tutanota.com
PostgreSQL version: 16.3
Operating system:   EndeavourOS (Arch Distro)
Description:

**Watch in a .md editor for better view**

I encountered significant issues when attempting to run PostgreSQL on my
EndeavourOS system. Despite following all standard installation procedures,
I was unable to start PostgreSQL or perform necessary administrative tasks
such as initializing the database. After trying multiple fixes, the only
solution was to modify `visudo` to allow `postgres` to run with
administrative privileges, which should not be necessary.

### **Steps to Reproduce**

1. Installed PostgreSQL via `pacman`:
   ```bash
   sudo pacman -S postgresql
   ```

2. Tried to initialize the PostgreSQL database:
   ```bash
   sudo su - postgres
   initdb --locale=C.UTF-8 --encoding=UTF8 -D '/var/lib/postgres/data'
   ```

3. Encountered permission issues:
   ```bash
   initdb: error: could not access directory "/var/lib/postgres/data":
Permission denied
   ```

4. I attempted the following common solutions:
   - Resetting the `postgres` user password.
   - Ensuring that the `postgres` user had the appropriate privileges and
was part of necessary groups.
   - Starting and enabling the PostgreSQL service via `systemctl`.
   
   None of these steps resolved the issue. I also attempted the recommended
commands such as:
   ```bash
   sudo -u postgres -i
   ```
   But continued to be prompted for a password, which was not accepted
despite resetting it multiple times.

5. The **only** workaround that enabled me to start PostgreSQL successfully
was modifying `visudo` to grant additional privileges to the `postgres`
user.

### **Expected Behavior**

PostgreSQL should run without needing to modify `visudo`. The default
installation and initialization procedures should allow the `postgres` user
to perform administrative tasks without requiring extra steps.

### **System Information**

To provide more insight into my system configuration, here are the specs of
my machine:

Operating System: EndeavourOS (Arch-based)
Kernel Version: 6.6.56-1-lts (64-bit)
Laptop Model: ASUS Vivobook M3401QA
CPU: AMD Ryzen 5 5600H (6 cores, 12 threads, base clock: 2.47 GHz, max
clock: 4.28 GHz)
GPU: AMD Radeon Vega (integrated)
Memory: 8 GB RAM (available: 7.17 GB, used: 6.08 GB)

### **Logs and Outputs**

Here are some relevant logs and error messages from my attempts:

1. **PostgreSQL Service Status:**
   ```bash
   sudo systemctl status postgresql.service
   ```
   Output:
   ```
   × postgresql.service - PostgreSQL database server
     Loaded: loaded (/usr/lib/systemd/system/postgresql.service; enabled;
preset: disabled)
     Active: failed (Result: exit-code) since [time];
     ...
     /var/lib/postgres/data is missing or empty.
     Failed with result 'exit-code'.
   ```

2. **Permission Denied Error on `initdb`:**
   ```bash
   initdb: error: could not access directory "/var/lib/postgres/data":
Permission denied
   ```

### **Solution Attempted**

I modified `/etc/sudoers` via `visudo` to allow `postgres` to run with more
privileges. This workaround allowed me to start PostgreSQL successfully, but
this is not ideal and should not be the expected behavior.

---

If this issue is specific to EndeavourOS or PostgreSQL on Arch-based
systems, it would be helpful to identify and address the root cause to
improve the experience for future users.