On my Linux Mint 19.1:
```bash
$ umask
0022
```

After the first run of `bitcoin-qt -sysperm=false` the `0700` permissions are expected for both the datadir (`~/.bitcoin`) and the walletdir (`~/.bitcoin/wallets`).

Actually, the directories are created with such access permissions:
```bash
$ stat ~/.bitcoin | grep Uid
Access: (0755/drwxr-xr-x)  Uid: ( 1000/ hebasto)   Gid: ( 1000/ hebasto)
$ stat ~/.bitcoin/wallets | grep Uid
Access: (0755/drwxr-xr-x)  Uid: ( 1000/ hebasto)   Gid: ( 1000/ hebasto)
```

Refs:
- #4286
- #13371
- #13389

NOTE: reading through the initial PR #4286 makes me think it was controversial. Is it a better and simpler way to just get rid of `-sysperm` option? I believe a user who needs this option can easily run `chown` command.
{
    LOCK(cs_args);
    m_cached_datadir_path = fs::path();
    m_cached_network_datadir_path = fs::path();
    m_cached_blocks_path = fs::path();
}
std::optional<const ArgsManager::Command> ArgsManager::GetCommand() const
{
    Command ret;
    LOCK(cs_args);
    auto it = m_command.begin();
    if (it == m_command.end()) {
        
        return std::nullopt;
    }
    if (!m_accept_any_command) {
        
        ret.command = *(it++);
    }
    while (it != m_command.end()) {
        
        ret.args.push_back(*(it++));
    }
    return ret;
}
std::vector<std::string> ArgsManager::GetArgs(const std::string& strArg) const