I am developing an application on qt5 using C++ which will support all popular distros, for this currently I am using QSysInfo
qDebug() << "currentCpuArchitecture():" << QSysInfo::currentCpuArchitecture();
qDebug() << "productType():" << QSysInfo::productType();
qDebug() << "productVersion():" << QSysInfo::productVersion();
qDebug() << "prettyProductName():" << QSysInfo::prettyProductName();
It returns ubuntu, manjaro... in prettyProductName, I actually need a base system like Debian, arch...
All Linux distros are just Linux so you need to read distro-specific values:
$ cat /etc/*-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=22.04
DISTRIB_CODENAME=jammy
DISTRIB_DESCRIPTION="Ubuntu 22.04.1 LTS"
PRETTY_NAME="Ubuntu 22.04.1 LTS"
NAME="Ubuntu"
VERSION_ID="22.04"
VERSION="22.04.1 LTS (Jammy Jellyfish)"
VERSION_CODENAME=jammy
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=jammy
The files are distro-specific and the information in those files are also distro-specific so the files and fields may differ from one distro to another. Some distro may not even have them
Similarly there's a common tool named lsb_release in most common distros and you can check its output if it exists
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.5 LTS
Release: 20.04
Codename: focal
If a rare distro doesn't have any of those then probably you're out of luck