Missing entry to install #17337

Bitcoin setup is not successfull on a clean ubuntu system following the install instructions https://github.com/bitcoin/bitcoin/blob/master/doc/build-unix.md

Expected behavior

I would expect that installation to complete and that my setup is able to build bitcoin

Actual behavior

Apparently ./configure gave this error: "configure: error: libdb_cxx headers missing, Bitcoin Core requires this library for wallet functionality (--disable-wallet to disable wallet functionality)". next make does not work

make
make: *** No targets specified and no makefile found.  Stop.
**System information**

To reproduce

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The bitcoin version this happens is b54666c849bad258d92d6d1e45a051d36055681e

**Fix ** there are many solutions specified in #2998 but for me the woking one was the comment #2998 (comment) from @bellaj

sudo add-apt-repository ppa:bitcoin/bitcoin
sudo apt-get update
sudo apt-get install libdb4.8-dev libdb4.8++-dev

So I guess this could be added to the ubuntu section of https://github.com/bitcoin/bitcoin/blob/master/doc/build-unix.md ?

So I guess this could be added to the ubuntu section of https://github.com/bitcoin/bitcoin/blob/master/doc/build-unix.md ?

From build-unix.md:

Ubuntu and Debian have their own libdb-dev and libdb++-dev packages, but these will install BerkeleyDB 5.1 or later. This will break binary wallet compatibility with the distributed executables, which are based on BerkeleyDB 4.8. If you do not care about wallet compatibility, pass --with-incompatible-bdb to configure.

Otherwise, you can build from self-compiled depends (see above).

For the wallet you need some version of BerkeleyDB. On Debian I usually just install the libdb++-dev (5.x), but if compatibility with the distributed binaries is important you need to use 4.8.

The supported cross-platform way to build BerkeleyDB 4.8 is to use the contrib/install_db4.sh script. This is mentioned in all the doc/build-*.md files.

(the PPA is another option, but as this relies on a third-party source, this is intentionally not mentioned)

https://launchpad.net/~bitcoin/+archive/ubuntu/bitcoin says "NOT MAINTAINED (for new versions of Ubuntu)", so I'd rather not use that.