sudo: false
language: python
python: 3.6
services:
    - postgresql
script:
    - which pg_ctl
    - echo $PATH
    - pg_config --bindir
    - ls -lh /usr/lib/postgresql/
    - ls -lh /usr/lib/postgresql/10/bin/
    - ls -lh /usr/lib/postgresql/10/bin/pg_ctl

...
$ which pg_ctl
The command "which pg_ctl" exited with 1.
$ echo $PATH
/home/travis/virtualenv/python3.6.3/bin:/home/travis/bin:/home/travis/.local/bin:/opt/pyenv/shims:/home/travis/.phpenv/shims:/home/travis/perl5/perlbrew/bin:/home/travis/.nvm/versions/node/v8.9.1/bin:/home/travis/.kiex/elixirs/elixir-1.4.5/bin:/home/travis/.kiex/bin:/home/travis/.rvm/gems/ruby-2.4.1/bin:/home/travis/.rvm/gems/ruby-2.4.1@global/bin:/home/travis/.rvm/rubies/ruby-2.4.1/bin:/home/travis/gopath/bin:/usr/local/phantomjs/bin:/usr/local/phantomjs:/usr/local/neo4j-3.2.7/bin:/usr/local/maven-3.5.2/bin:/usr/local/cmake-3.9.2/bin:/usr/local/clang-5.0.0/bin:/home/travis/.gimme/versions/go1.7.4.linux.amd64/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/home/travis/.rvm/bin:/home/travis/.phpenv/bin:/opt/pyenv/bin:/home/travis/.yarn/bin
The command "echo $PATH" exited with 0.
$ pg_config --bindir
/usr/lib/postgresql/10/bin
The command "pg_config --bindir" exited with 0.
$ ls -lh /usr/lib/postgresql/
total 0
drwxr-xr-x 4 root root 26 Dec  5 19:59 9.2
drwxr-xr-x 4 root root 26 Dec  5 19:59 9.3
drwxr-xr-x 4 root root 26 Dec  5 20:00 9.4
drwxr-xr-x 4 root root 26 Dec  5 20:00 9.5
drwxr-xr-x 4 root root 26 Dec  5 20:00 9.6
The command "ls -lh /usr/lib/postgresql/" exited with 0.
$ ls -lh /usr/lib/postgresql/10/bin/
ls: cannot access /usr/lib/postgresql/10/bin/: No such file or directory
...