cut, awk, head, bash, etc are easy enough, but am I overlooking some intrinsic method of getting just PG's primary version number (9.6 or 14, in my case) without doing substring manipulation?
$ ssh foo.example.com pg_config --version
PostgreSQL 9.6.24
$ ssh foo.example.com psql --version
psql (PostgreSQL) 9.6.24
$ psql -h foo.example.com -Xtc "SELECT version();"
PostgreSQL 9.6.24 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-44), 64-bit
PostgreSQL 9.6.24
$ ssh foo.example.com psql --version
psql (PostgreSQL) 9.6.24
$ psql -h foo.example.com -Xtc "SELECT version();"
PostgreSQL 9.6.24 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-44), 64-bit
$ ssh bar.example.com pg_config --version
PostgreSQL 14.12
$ ssh bar.example.com psql --version
psql (PostgreSQL) 14.12
$ psql -h bar.example.com -Xtc "SELECT version();"
PostgreSQL 14.12 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 8.5.0 20210514 (Red Hat 8.5.0-20), 64-bit
PostgreSQL 14.12
$ ssh bar.example.com psql --version
psql (PostgreSQL) 14.12
$ psql -h bar.example.com -Xtc "SELECT version();"
PostgreSQL 14.12 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 8.5.0 20210514 (Red Hat 8.5.0-20), 64-bit