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<refentry id="gtk-compiling">
<refmeta>
<refentrytitle>Compiling GTK Applications</refentrytitle>
<manvolnum>3</manvolnum>
<refmiscinfo>GTK Library</refmiscinfo>
</refmeta>

<refnamediv>
<refname>Compiling GTK Applications</refname>
<refpurpose>
How to compile your GTK application
</refpurpose>
</refnamediv>

<refsect1>
<title>Compiling GTK Applications on UNIX</title>

<para>
To compile a GTK application, you need to tell the compiler where to
find the GTK header files and libraries. This is done with the
<literal>pkg-config</literal> utility.
</para>
<para>
The following interactive shell session demonstrates how
<literal>pkg-config</literal> is used (the actual output on
your system may be different):
<programlisting>
$ pkg-config --cflags gtk4
 -pthread -I/usr/include/gtk-4.0 -I/usr/lib64/gtk-4.0/include -I/usr/include/atk-1.0 -I/usr/include/cairo -I/usr/include/pango-1.0 -I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include -I/usr/include/pixman-1 -I/usr/include/freetype2 -I/usr/include/libpng12
$ pkg-config --libs gtk4
 -pthread -lgtk-4 -lgdk-4 -latk-1.0 -lgio-2.0 -lpangoft2-1.0 -lgdk_pixbuf-2.0 -lpangocairo-1.0 -lcairo -lpango-1.0 -lfreetype -lfontconfig -lgobject-2.0 -lgmodule-2.0 -lgthread-2.0 -lrt -lglib-2.0
</programlisting>
</para>
<para>
The simplest way to compile a program is to use the "backticks"
feature of the shell. If you enclose a command in backticks
(<emphasis>not single quotes</emphasis>), then its output will be
substituted into the command line before execution. So to compile
a GTK Hello, World, you would type the following:
<programlisting>
$ cc `pkg-config --cflags gtk4` hello.c -o hello `pkg-config --libs gtk4`
</programlisting>
</para>

<para>
Deprecated GTK functions are annotated to make the compiler
emit warnings when they are used (e.g. with gcc, you need to use
the -Wdeprecated-declarations option). If these warnings are
problematic, they can be turned off by defining the preprocessor
symbol <link linkend="GDK-DISABLE-DEPRECATION-WARNINGS:CAPS"><literal>GDK_DISABLE_DEPRECATION_WARNINGS</literal></link> by using the commandline
option <literal>-DGDK_DISABLE_DEPRECATION_WARNINGS</literal>
</para>

<para>
GTK deprecation annotations are versioned; by defining the
macros <link linkend="GDK-VERSION-MIN-REQUIRED:CAPS"><literal>GDK_VERSION_MIN_REQUIRED</literal></link> and <link linkend="GDK-VERSION-MAX-ALLOWED:CAPS"><literal>GDK_VERSION_MAX_ALLOWED</literal></link>,
you can specify the range of GTK versions whose API you want
to use. APIs that were deprecated before or introduced after
this range will trigger compiler warnings.
</para>

<para>
Here is how you would compile hello.c if you want to allow it
to use symbols that were not deprecated in 4.2:
<programlisting>
$ cc `pkg-config --cflags gtk4` -DGDK_VERSION_MIN_REQIRED=GDK_VERSION_4_2 hello.c -o hello `pkg-config --libs gtk4`
</programlisting>
</para>

<para>
And here is how you would compile hello.c if you don't want
it to use any symbols that were introduced after 4.2:
<programlisting>
$ cc `pkg-config --cflags gtk4` -DGDK_VERSION_MAX_ALLOWED=GDK_VERSION_4_2 hello.c -o hello `pkg-config --libs gtk4`
</programlisting>
</para>

<para>
The older deprecation mechanism of hiding deprecated interfaces
entirely from the compiler by using the preprocessor symbol
GTK_DISABLE_DEPRECATED is still used for deprecated macros,
enumeration values, etc. To detect uses of these in your code,
use the commandline option <literal>-DGTK_DISABLE_DEPRECATED</literal>.
There are similar symbols GDK_DISABLE_DEPRECATED,
GDK_PIXBUF_DISABLE_DEPRECATED and G_DISABLE_DEPRECATED for GDK, GdkPixbuf and
GLib.
</para>

</refsect1>
</refentry>
