September 26, 2024: PostgreSQL 17 Released!
Supported Versions: Current (17) / 16 / 15 / 14 / 13 / 12
Development Versions: devel
Unsupported versions: 11 / 10 / 9.6 / 9.5 / 9.4 / 9.3 / 9.2 / 9.1 / 9.0 / 8.4 / 8.3 / 8.2 / 8.1 / 8.0 / 7.4 / 7.3 / 7.2 / 7.1
This documentation is for an unsupported version of PostgreSQL.
You may want to view the same page for the current version, or one of the other supported versions listed above instead.

Chapter 1. PostgreSQL Source Code

1.1. Formatting

Source code formatting uses a 4 column tab spacing, currently with tabs preserved (i.e. tabs are not expanded to spaces).

For Emacs, add the following (or something similar) to your ~/.emacs initialization file:

;; check for files with a path containing "postgres" or "pgsql"
(setq auto-mode-alist
  (cons '("\\(postgres\\|pgsql\\).*\\.[ch]\\'" . pgsql-c-mode)
        auto-mode-alist))
(setq auto-mode-alist
  (cons '("\\(postgres\\|pgsql\\).*\\.cc\\'" . pgsql-c-mode)
        auto-mode-alist))

(defun pgsql-c-mode ()
  ;; sets up formatting for PostgreSQL C code
  (interactive)
  (c-mode)
  (setq-default tab-width 4)
  (c-set-style "bsd")             ; set c-basic-offset to 4, plus other stuff
  (c-set-offset 'case-label '+)   ; tweak case indent to match PG custom
  (setq indent-tabs-mode t))      ; make sure we keep tabs when indenting

For vi, your ~/.vimrc or equivalent file should contain the following:

set tabstop=4

or equivalently from within vi, try

:set ts=4

The text browsing tools more and less can be invoked as

more -x4
less -x4