installing MacPorts 2.6.2 on Ubuntu Linux 20.04

[Ken Cunningham]

I thought I would start up a short thread on progress with this -- 
MacPorts on Linux. We've long written the Portfiles with this in mind. 
This was done on an Intel system, with the current Ubuntu 20.04. Ubuntu 
19.10 can be installed in a VM in parallels, and no doubt in other VM 
systems.

Some quick notes:

apt is the built-in package manager, similar to "port".

"sudo apt install" is the same as "sudo port install".

"apt info" is "port info"

"apt-file show" does something similar to "port contents", but the 
software does not have to be installed.


After downloading the MacPorts source tarball, and prior to building 
MacPorts, you must install the supporting software that comes already on 
Macs that MacPorts expects to find.

These were installed as:

sudo apt install mtree-netbsd
sudo apt install tcl8.6
sudo apt install curl
sudo apt install sqlite3
sudo apt install gnustep
sudo apt install libcurl4-gnutls-dev
sudo apt install libsqlite3-dev


my system already had llvm-10 and clang-10 installed, and there was 
already a symlink "port" linking /usr/bin/clang to the selected clang 
binary, in this case clang-10.

Then build and install MacPorts as usual, into /opt/local

./configure && make && sudo make install


Add to your PATH as usual, but on Ubuntu, by editing ".bashrc", adding:

export PATH=/opt/local/bin:/opt/local/sbin:$PATH


Adding that PATH to the sudo command is harder -- it doesn't pick it up 
from the above ".bashrc". You have add it to the sudoers command with:

sudo visudo

and then add it to the secure_path

Defaults 
secure_path="/opt/local/bin:/opt/local/sbin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin"

There are some differences between Darwin and Ubuntu, and to work around 
some of these that are not already compensated for by MacPorts base, I 
did this:


edit macports.conf

sudo gedit /opt/local/etc/macports/macports.conf

and add:

buildmakejobs            2                  # or a more appropriate 
number for your processor count
default_compilers      clang            # compiler selection is broken, 
this chooses /usr/bin/clang which works best with macport's portfiles
cxx_stdlib                   libstdc++     # configure.cxx_stdlib seems 
broken, this fills in appropriate default


After that, darwin and ubuntu supply 'sed' in different locations, so 
rather than edit 200 Portfiles, you can do this:

sudo ln -s /bin/sed /usr/bin/sed


and then you're up and running. Ports will at least start to build. 
There are a number of hiccups, where the portfile logic does not allow a 
path where the platform is other than "darwin" -- e.g. libuv, but these 
are easy to spot and easy to fix if desired. Some things appear harder 
to fix, like "m4" which I have not yet sorted out.


And then you can play around. I don't know if MacPorts on Ubuntu (or any 
other flavour of Linux) will ever be popular, but you can at least get 
started.


Best,


Ken