types.sgml

GLib是GTK+和GNOME工程的基础底层核心程序库

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Basic Types

<!-- ##### SECTION Short_Description ##### -->
standard GLib types, defined for ease-of-use and portability.

<!-- ##### SECTION Long_Description ##### -->
<para>
GLib defines a number of commonly used types, which can be divided into
4 groups:

<itemizedlist>
<listitem><para>
New types which are not part of standard C - #gboolean, #gsize, #gssize.
</para></listitem>

<listitem><para>
Integer types which are guaranteed to be the same size across all platforms -
#gint8, #guint8, #gint16, #guint16, #gint32, #guint32, #gint64, #guint64.
</para></listitem>

<listitem><para>
Types which are easier to use than their standard C counterparts -
#gpointer, #gconstpointer, #guchar, #guint, #gushort, #gulong.
</para></listitem>

<listitem><para>
Types which correspond exactly to standard C types, but are included
for completeness - #gchar, #gint, #gshort, #glong, #gfloat, #gdouble.
</para></listitem>
</itemizedlist>

</para>

<!-- ##### SECTION See_Also ##### -->
<para>

</para>

<!-- ##### TYPEDEF gboolean ##### -->
<para>
A standard <type>boolean</type> type.
Variables of this type should only contain the value #TRUE or #FALSE.
</para>


<!-- ##### TYPEDEF gpointer ##### -->
<para>
An untyped pointer.
#gpointer looks better and is easier to use than <type>void*</type>.
</para>


<!-- ##### TYPEDEF gconstpointer ##### -->
<para>
An untyped pointer to constant data.
The data pointed to should not be changed.
</para>
<para>
This is typically used in function prototypes to indicate that the
data pointed to will not be altered by the function.
</para>


<!-- ##### TYPEDEF gchar ##### -->
<para>
Corresponds to the standard C <type>char</type> type.
</para>


<!-- ##### TYPEDEF guchar ##### -->
<para>
Corresponds to the standard C <type>unsigned char</type> type.
</para>


<!-- ##### TYPEDEF gint ##### -->
<para>
Corresponds to the standard C <type>int</type> type.
Values of this type can range from #G_MININT to #G_MAXINT.
</para>


<!-- ##### TYPEDEF guint ##### -->
<para>
Corresponds to the standard C <type>unsigned int</type> type.
Values of this type can range from 0 to #G_MAXUINT.
</para>


<!-- ##### TYPEDEF gshort ##### -->
<para>
Corresponds to the standard C <type>short</type> type.
Values of this type can range from #G_MINSHORT to #G_MAXSHORT.
</para>


<!-- ##### TYPEDEF gushort ##### -->
<para>
Corresponds to the standard C <type>unsigned short</type> type.
Values of this type can range from 0 to #G_MAXUSHORT.
</para>


<!-- ##### TYPEDEF glong ##### -->
<para>
Corresponds to the standard C <type>long</type> type.
Values of this type can range from #G_MINLONG to #G_MAXLONG.
</para>


<!-- ##### TYPEDEF gulong ##### -->
<para>
Corresponds to the standard C <type>unsigned long</type> type.
Values of this type can range from 0 to #G_MAXULONG.
</para>


<!-- ##### TYPEDEF gint8 ##### -->
<para>
A signed integer guaranteed to be 8 bits on all platforms.
Values of this type can range from -128 to 127.
</para>


<!-- ##### TYPEDEF guint8 ##### -->
<para>
An unsigned integer guaranteed to be 8 bits on all platforms.
Values of this type can range from 0 to 255.
</para>


<!-- ##### TYPEDEF gint16 ##### -->
<para>
A signed integer guaranteed to be 16 bits on all platforms.
Values of this type can range from -32,768 to 32,767.
</para>


<!-- ##### TYPEDEF guint16 ##### -->
<para>
An unsigned integer guaranteed to be 16 bits on all platforms.
Values of this type can range from 0 to 65,535.
</para>


<!-- ##### TYPEDEF gint32 ##### -->
<para>
A signed integer guaranteed to be 32 bits on all platforms.
Values of this type can range from -2,147,483,648 to 2,147,483,647.
</para>


<!-- ##### TYPEDEF guint32 ##### -->
<para>
An unsigned integer guaranteed to be 32 bits on all platforms.
Values of this type can range from 0 to 4,294,967,295.
</para>


<!-- ##### MACRO G_HAVE_GINT64 ##### -->
<para>
This macro is defined if 64-bit signed and unsigned integers are available
on the platform.
</para>



<!-- ##### TYPEDEF gint64 ##### -->
<para>
A signed integer guaranteed to be 64 bits on all platforms on which it is
available (see #G_HAVE_GINT64).
Values of this type can range from -9,223,372,036,854,775,808 to
9,223,372,036,854,775,807.
</para>


<!-- ##### TYPEDEF guint64 ##### -->
<para>
An unsigned integer guaranteed to be 64 bits on all platforms on which it is
available (see #G_HAVE_GINT64).
Values of this type can range from 0 to 18,446,744,073,709,551,615.
</para>


<!-- ##### MACRO G_GINT64_CONSTANT ##### -->
<para>
This macro is used to insert 64-bit integer literals into the source code.
</para>

@val: a literal integer value, e.g. 0x1d636b02300a7aa7U.


<!-- ##### TYPEDEF gfloat ##### -->
<para>
Corresponds to the standard C <type>float</type> type.
Values of this type can range from #G_MINFLOAT to #G_MAXFLOAT.
</para>


<!-- ##### TYPEDEF gdouble ##### -->
<para>
Corresponds to the standard C <type>double</type> type.
Values of this type can range from #G_MINDOUBLE to #G_MAXDOUBLE.
</para>


<!-- ##### TYPEDEF gsize ##### -->
<para>
An unsigned 32-bit integer intended to represent sizes of data structures.
</para>


<!-- ##### TYPEDEF gssize ##### -->
<para>
A signed 32-bit integer intended to represent sizes of data structures.
</para>