How to check if command line tools is installed

Question

I have a macbook pro with OS X 10.8.2. XCode is installed. I know this as it appears in the Applications directory. There are also the xcodebuild and xcode-select files in /

Answer 1

I think the simplest way which worked for me to find Command line tools is installed or not and its version irrespective of what macOS version is

$brew config

macOS: 10.14.2-x86_64
CLT: 10.1.0.0.1.1539992718
Xcode: 10.1

This when you have Command Line tools properly installed and paths set properly.

Earlier i got output as below
macOS: 10.14.2-x86_64
CLT: N/A
Xcode: 10.1

CLT was shown as N/A in spite of having gcc and make working fine and below outputs

$xcode-select -p              
/Applications/Xcode.app/Contents/Developer
$pkgutil --pkg-info=com.apple.pkg.CLTools_Executables
No receipt for 'com.apple.pkg.CLTools_Executables' found at '/'.
$brew doctor
Your system is ready to brew.

Finally doing xcode-select --install resolved my issue of brew unable to find CLT for installing packages as below.

Installing sphinx-doc dependency: python
Warning: Building python from source:
  The bottle needs the Apple Command Line Tools to be installed.
  You can install them, if desired, with:
    xcode-select --install