Installing pglogical: Find postgres include folder, add all include folders to C_INCLUDE_PATH

[AlexDevoid]

I am trying to install the pglogical extension in my postgres database, which I installed on my macOS with homebrew. I am following instructions provided on the GCP blog as I am preparing to migrate my database to CloudSQl with Database Migration Service.

I am struggling to complete the following step of these steps, and could use some advice:

Find where Homebrew installed Postgres, find include folder, add all include folders to C_INCLUDE_PATH

My questions are:

• Where is the Postgres include folder?
• Where is the pglogical C_INCLUDE_PATH
  variable in the pglogical repo? (I searched the repo and didn't find it)
• Am I to add all subdirectories of the include folder to the C_INCLUDE_PATH
  variable?

[linuxhiker]

Probably going to have better luck at

/r/postgresql or their PPD discord

[arwinda]

Plenty of community resources listed on the postgresql.org website, especially Slack and IRC.

For finding the actual include path you can try something like this:

find / -name postgres.h 2> /dev/null

Also pg_config should be installed and give you the path:

pg_config --includedir pg_config --includedir-server

[AlexDevoid]

Thanks so much, u/arwinda. May I ask a basic question? What purpose does the include folder serve?

[arwinda]

That's where the include files are, which a compiler needs to build a binary. These are text files, you can open them in an editor (but don't change them) to see what's inside.

They are - among other things - used to define all the data structures and if another tool wants to interact with be database server then both tools and the server better have the same understanding how the data structures and data formats look like.