## 14.2. Requirements

In general, a modern Unix-compatible platform should be able to run PostgreSQL. The platforms that had received specific testing at the time of release are listed in Section 14.7, “Supported Platforms” below. In the `doc` subdirectory of the distribution there are several platform-specific FAQ documents you might wish to consult if you are having trouble.

The following software packages are required for building PostgreSQL:

- GNU make is required; other make programs will not work. GNU make is often installed under the name `gmake`; this document will always refer to it by that name. (On some systems GNU make is the default tool with the name `make`.) To test for GNU make enter

      gmake --version

  It is recommended to use version 3.76.1 or later.

- You need an ISO/ANSI C compiler. Recent versions of GCC are recommendable, but PostgreSQL is known to build with a wide variety of compilers from different vendors.

- tar is required to unpack the source distribution in the first place, in addition to either gzip or bzip2.

- The GNU Readline library (for comfortable line editing and command history retrieval) will be used by default. If you don't want to use it then you must specify the `--without-readline` option for `configure`. (On NetBSD, the `libedit` library is Readline-compatible and is used if `libreadline` is not found.) If you are using a package-based Linux distribution, be aware that you need both the `readline` and `readline-devel` packages, if those are separate in your distribution.

- The zlib compression library will be used by default. If you don't want to use it then you must specify the `--without-zlib` option for `configure`. Using this option disables support for compressed archives in pg_dump and pg_restore.

- Additional software is needed to build PostgreSQL on Windows. You can build PostgreSQL for NT-based versions of Windows (like Windows XP and 2003) using MinGW; see `doc/FAQ_MINGW` for details. You can also build PostgreSQL using Cygwin; see `doc/FAQ_CYGWIN`. A Cygwin-based build will work on older versions of Windows, but if you have a choice, we recommend the MinGW approach. While these are the only tool sets recommended for a complete build, it is possible to build just the C client library (libpq) and the interactive terminal (psql) using other Windows tool sets. For details of that see Chapter 15, Client-Only Installation on Windows.

The following packages are optional. They are not required in the default configuration, but they are needed when certain build options are enabled, as explained below.

- To build the server programming language PL/Perl you need a full Perl installation, including the `libperl` library and the header files. Since PL/Perl will be a shared library, the `libperl` library must be a shared library also on most platforms. This appears to be the default in recent Perl versions, but it was not in earlier versions, and in any case it is the choice of whomever installed Perl at your site.

  If you don't have the shared library but you need one, a message like this will appear during the build to point out this fact:

      *** Cannot build PL/Perl because libperl is not a shared library.
      *** You might have to rebuild your Perl installation.  Refer to
      *** the documentation for details.

  (If you don't follow the on-screen output you will merely notice that the PL/Perl library object, `plperl.so` or similar, will not be installed.) If you see this, you will have to rebuild and install Perl manually to be able to build PL/Perl. During the configuration process for Perl, request a shared library.

- To build the PL/Python server programming language, you need a Python installation with the header files and the distutils module. The distutils module is included by default with Python 1.6 and later; users of earlier versions of Python will need to install it.

  Since PL/Python will be a shared library, the `libpython` library must be a shared library also on most platforms. This is not the case in a default Python installation. If after building and installing you have a file called `plpython.so` (possibly a different extension), then everything went well. Otherwise you should have seen a notice like this flying by:

      *** Cannot build PL/Python because libpython is not a shared library.
      *** You might have to rebuild your Python installation.  Refer to
      *** the documentation for details.

  That means you have to rebuild (part of) your Python installation to supply this shared library.

  If you have problems, run Python 2.3 or later's configure using the `--enable-shared` flag. On some operating systems you don't have to build a shared library, but you will have to convince the PostgreSQL build system of this. Consult the `Makefile` in the `src/pl/plpython` directory for details.

- If you want to build the PL/Tcl procedural language, you of course need a Tcl installation.

- To enable Native Language Support (NLS), that is, the ability to display a program's messages in a language other than English, you need an implementation of the Gettext API. Some operating systems have this built-in (e.g., Linux, NetBSD, Solaris), for other systems you can download an add-on package from http://developer.postgresql.org/~petere/bsd-gettext/. If you are using the Gettext implementation in the GNU C library then you will additionally need the GNU Gettext package for some utility programs. For any of the other implementations you will not need it.

- Kerberos, OpenSSL, and/or PAM, if you want to support authentication or encryption using these services.

If you are building from a CVS tree instead of using a released source package, or if you want to do development, you also need the following packages:

- GNU Flex and Bison are needed to build a CVS checkout or if you changed the actual scanner and parser definition files. If you need them, be sure to get Flex 2.5.4 or later and Bison 1.875 or later. Other yacc programs can sometimes be used, but doing so requires extra effort and is not recommended. Other lex programs will definitely not work.

If you need to get a GNU package, you can find it at your local GNU mirror site (see http://www.gnu.org/order/ftp.html for a list) or at ftp://ftp.gnu.org/gnu/.

Also check that you have sufficient disk space. You will need about 65 MB for the source tree during compilation and about 15 MB for the installation directory. An empty database cluster takes about 25 MB, databases take about five times the amount of space that a flat text file with the same data would take. If you are going to run the regression tests you will temporarily need up to an extra 90 MB. Use the `df` command to check free disk space.