[ fromfile: setup-nix.xml id: setup-nix ]

Open source development tools (ssh, bash, gcc) are available natively on most UNIX-derived platforms.^[135]

When we discuss something that's specific to UNIX-derived platforms (Linux, BSD, Solaris, etc), we will use the shorthand *nix for "most flavors of UNIX."

Another important acronym is POSIX, which stands for Portable Operating System Interface for UNIX. The development of this family of Application Programming Interface (API) standards was sponsored by the IEEE (Institute of Electrical and Electronics Engineers), an organization for engineers, scientists, and students, best known for developing standards for the computer and electronics industry.^[136]

This section is for readers who use a computer with a *nix system installed.

The first step to prepare your computer for this book is to make sure that the full installation of Qt is available to you. This includes, in addition to the source and compiled library code, the Qt Assistant documentation system, program examples, and the Qt Designer program.

To see which (if any) version of Qt has already been installed on your system, start with the commands:

which qmake
qmake -v

The output of the first command tells you where the qmake executable is located. If that output looks like this: bash: qmake: command not found, it is possible that

If you can run it, qmake -v provides version information. If it reports Using Qt version 4.x.y, use the which command to check whether these other Qt tools are available: moc, uic, assistant, designer, and qtcreator.

If these executables are all found and match versions, Qt is installed and ready to use.

If these tests indicate that you have an earlier version or no Qt installed, or that you are missing some components of Qt, then you need to build or install the latest release of Qt and select the Qt executables as defaults in your path.

[ROOT@lazarus]# apt-cache search qt4
libqt4-assistant - transitional package for Qt 4 assistant module
libqt4-core - trans pkg for Qt 4 core non-GUI runtime libraries
libqt4-dbg - Qt 4 library debugging symbols
libqt4-dbus - Qt 4 D-Bus module
libqt4-declarative - Qt 4 Declarative module
libqt4-declarative-folderlistmodel - Qt 4 folderlistmodel QML plugin
libqt4-declarative-gestures - Qt 4 gestures QML plugin
libqt4-declarative-particles - Qt 4 particles QML plugin
libqt4-designer - Qt 4 designer module
libqt4-dev - Qt 4 development files
libqt4-gui - transitional package for Qt 4 GUI runtime libraries
libqt4-help - Qt 4 help module
libqt4-network - Qt 4 network module
libqt4-opengl - Qt 4 OpenGL module
libqt4-opengl-dev - Qt 4 OpenGL library development files
libqt4-phonon - Qt 4 Phonon module
libqt4-qt3support - Qt 3 compatibility library for Qt 4
libqt4-script - Qt 4 script module
libqt4-scripttools - Qt 4 script tools module
libqt4-sql - Qt 4 SQL module
libqt4-sql-ibase - Qt 4 InterBase/FireBird database driver
libqt4-sql-mysql - Qt 4 MySQL database driver
libqt4-sql-odbc - Qt 4 ODBC database driver
libqt4-sql-psql - Qt 4 PostgreSQL database driver
libqt4-sql-sqlite - Qt 4 SQLite 3 database driver
libqt4-sql-sqlite2 - Qt 4 SQLite 2 database driver
libqt4-sql-tds - Qt 4 FreeTDS database driver
libqt4-svg - Qt 4 SVG module
libqt4-test - Qt 4 test module
libqt4-webkit - transitional package for Qt 4 WebKit module
libqt4-webkit-dbg - trans pkg for Qt 4 WebKit debugging symbols
libqt4-xml - Qt 4 XML module
libqt4-xmlpatterns - Qt 4 XML patterns module
libqt4-xmlpatterns-dbg - Qt 4 XML patterns library debugging symbols
qt4-demos - Qt 4 examples and demos
qt4-demos-dbg - Qt 4 examples and demos debugging symbols
qt4-designer - graphical designer for Qt 4 applications
qt4-dev-tools - Qt 4 development tools
qt4-doc - Qt 4 API documentation
qt4-doc-html - Qt 4 API documentation (HTML format)
qt4-qmake - Qt 4 qmake Makefile generator tool
qt4-qmlviewer - Qt 4 QML viewer
qt4-qtconfig - Qt 4 configuration tool
[ROOT@lazarus]#

You can download, unpack, and compile the latest open source tarball from qt.nokia.com. If you have the Qt SDK, you can run the Updater and select Qt Sources, to download it into your Qt SDK directory. Be sure to also select demos and examples.

	Installing dependencies
	In Debian, it is possible with a single command to automatically install all the tools and libraries you need to build another Debian package. You can take advantage of this, when you want to build any popular open source tool from source. For more information, see Appendix D. apt-get build-dep libqt4-dev

Note

A tarball is a file produced by the tar command (tape archive) that can combine many files, as specified in the command-line, into one file (which is generally given the extension .tar) for ease of storage or transfer. The combined file is generally compressed using a utility like gzip or bzip2, which appends the extension .gz or .bz to the tar file. The command-line for unpacking a tarball depends on how it was created. You can usually determine this from its extension. tar -vxf whatever.tar // uses the "verbose" switch tar -zxf whatever.tar.gz // compressed with gzip tar -zxf whatever.tgz // also compressed with gzip tar -jxf whatever.tar.bz2 // compressed with bzip2 A tar file can preserve directory structures and has many options and switches. You can read the online documentation for these utilities by typing info tar info gzip info bzip

The Qt source tarball contains the complete source code of the Qt library, plus numerous examples, tutorials, and extensions with full reference documentation. The tarball contains simple installation instructions (in the README and INSTALL files) and a configure --help message. Be sure to read the README file before you attempt to install software from any open source tarball.

Compiling from source can take 2 to 3 hours (depending on the speed of your system), but it is worth the time. Example E.1 shows the options we used to configure Qt 4.7.

#!/bin/sh
# specify -phonon if you want to build the audiojukebox exercise or
any of the Phonon examples.
# replace username with your username, and Qt473 with your version of
Qt
./configure -phonon -debug-and-release -fast

After Qt is configured, type make and then install it.

	Tip
	If you have a four-core processor, try typing make -j 4 and the compiler will run four compile processes simultaneously, taking full advantage of your extra cores.

In the final step, make install copies the executables and headers into another location from the unzipped tarball source tree. If you are installing in a common location, you need to be root to do this.

Tip

After installation, type the command qmake -v to determine which version of qmake is found by your shell. For systems that have more than one version installed, this is especially important to do. [ezust@stan] /home/ezust> which qmake which qmake /usr/local/Trolltech/QtSDK/Desktop/Qt/473/gcc/bin/qmake [ezust@cerberus] /home/ezust> qmake -version QMake version 2.01a Using Qt version 4.7.3 in /usr/local/Trolltech/QtSDK/Desktop/Qt/473/gcc/lib

After installing, check your environment variables and make sure that your PATH contains proper references to the built installed Qt.

	Tip
	The bash command env displays the current values of all your environment variables. Environment variables are discussed and used in Section 7.2.

Example E.2 shows how you can set the values of environment variables with bash, but the actual values depend on where the files are located on your system.

# Using the Qt SDK 1.1
# None of the variables below are required by Qt
# I just like having variables pointing to these locations for easy access:
export QTSDK=/opt/QtSDK
export QTCREATOR=$QTSDK/QtCreator
export QTDIR=$QTSDK/Desktop/Qt/473/gcc
export QTSRC=$QTSDK/QtSources/4.7.3

# make sure SDK's qmake and qtcreator are found first in the path:
export PATH=$QTDIR/bin:$QTCREATOR/bin:$PATH

# Location of your shared libraries: 
export CPPLIBS=~/cs331/projects/libs

# Where to search for shared object libraries at runtime:
export LD_LIBRARY_PATH=$CPPLIBS