$ ls -l
total 64
drwxr-x--- 6 postgres dba    54 May 21 16:54 base
-rw-r----- 1 postgres dba    44 May 26 00:00 current_logfiles
drwxr-x--- 2 postgres dba  4096 May 25 10:34 global
drwxr-x--- 2 postgres dba   166 May 26 00:00 log
drwxr-x--- 2 postgres dba     6 May 21 10:41 pg_commit_ts
drwxr-x--- 2 postgres dba     6 May 21 10:41 pg_dynshmem
-rw-r----- 1 postgres dba  4901 May 21 10:45 pg_hba.conf
-rw-r----- 1 postgres dba  1636 May 21 10:41 pg_ident.conf
drwxr-x--- 4 postgres dba    68 May 26 09:19 pg_logical
drwxr-x--- 4 postgres dba    36 May 21 10:41 pg_multixact
drwxr-x--- 2 postgres dba    18 May 25 10:33 pg_notify
drwxr-x--- 2 postgres dba     6 May 21 10:41 pg_replslot
drwxr-x--- 2 postgres dba     6 May 21 10:41 pg_serial
drwxr-x--- 2 postgres dba     6 May 21 10:41 pg_snapshots
drwxr-x--- 2 postgres dba     6 May 25 10:33 pg_stat
drwxr-x--- 2 postgres dba    84 May 26 17:47 pg_stat_tmp
drwxr-x--- 2 postgres dba    18 May 21 10:41 pg_subtrans
drwxr-x--- 2 postgres dba     6 May 21 10:41 pg_tblspc
drwxr-x--- 2 postgres dba     6 May 21 10:41 pg_twophase
-rw-r----- 1 postgres dba     3 May 21 10:41 PG_VERSION
lrwxrwxrwx 1 postgres dba    12 May 21 10:41 pg_wal -> /opt/wal6000
drwxr-x--- 2 postgres dba    18 May 21 10:41 pg_xact
-rw-r----- 1 postgres dba    88 May 21 10:41 postgresql.auto.conf
-rw-r----- 1 postgres dba 26679 May 25 10:33 postgresql.conf
-rw-r----- 1 postgres dba    23 May 25 10:33 postmaster.opts
$ more PG_VERSION
12
$ file PG_VERSION
PG_VERSION: ASCII text
$

注释：PG_VERSION 一个包含了PG主版本号的文件，可以直接打开