If you’re running ‘autogen.sh’ on the Bitcoin Core source code in Ubuntu and get an error like ‘Makefile.am:8: error: Libtool library used but ‘LIBTOOL’ is undefined’, it means the ‘libtool’ package is missing.
Install libtool in Ubuntu using the following command:
sudo apt install libtool
Try to run ‘autogen.sh’ again.
If you run ‘./configure’ and get this error: ‘configure: error: PKG_PROG_PKG_CONFIG macro not found. Please install pkg-config and re-run autogen.sh.’
Install pkg config:
sudo apt install pkg-config