GLib Reference Manual  

#include <glib.h> typedef gboolean; typedef gpointer; typedef gconstpointer; typedef gchar; typedef guchar; typedef gint; typedef guint; typedef gshort; typedef gushort; typedef glong; typedef gulong; typedef gint8; typedef guint8; typedef gint16; typedef guint16; typedef gint32; typedef guint32; #define G_HAVE_GINT64 typedef gint64; GLIB_VAR guint64 (); #define G_GINT64_CONSTANT (val) #define G_GUINT64_CONSTANT (val) typedef gfloat; typedef gdouble; typedef gsize; typedef gssize; typedef goffset;
GLib defines a number of commonly used types, which can be divided into 4 groups:
New types which are not part of standard C  gboolean, gsize, gssize.
Integer types which are guaranteed to be the same size across all platforms  gint8, guint8, gint16, guint16, gint32, guint32, gint64, guint64.
Types which are easier to use than their standard C counterparts  gpointer, gconstpointer, guchar, guint, gushort, gulong.
Types which correspond exactly to standard C types, but are included for completeness  gchar, gint, gshort, glong, gfloat, gdouble.
typedef gint gboolean;
A standard boolean type.
Variables of this type should only contain the value TRUE
or FALSE
.
typedef void* gpointer;
An untyped pointer. gpointer looks better and is easier to use than void*.
typedef const void *gconstpointer;
An untyped pointer to constant data. The data pointed to should not be changed.
This is typically used in function prototypes to indicate that the data pointed to will not be altered by the function.
typedef int gint;
Corresponds to the standard C int type. Values of this type can range from G_MININT to G_MAXINT.
typedef unsigned int guint;
Corresponds to the standard C unsigned int type. Values of this type can range from 0 to G_MAXUINT.
typedef short gshort;
Corresponds to the standard C short type. Values of this type can range from G_MINSHORT to G_MAXSHORT.
typedef unsigned short gushort;
Corresponds to the standard C unsigned short type. Values of this type can range from 0 to G_MAXUSHORT.
typedef long glong;
Corresponds to the standard C long type. Values of this type can range from G_MINLONG to G_MAXLONG.
typedef unsigned long gulong;
Corresponds to the standard C unsigned long type. Values of this type can range from 0 to G_MAXULONG.
typedef signed char gint8;
A signed integer guaranteed to be 8 bits on all platforms. Values of this type can range from 128 to 127.
typedef unsigned char guint8;
An unsigned integer guaranteed to be 8 bits on all platforms. Values of this type can range from 0 to 255.
typedef signed short gint16;
A signed integer guaranteed to be 16 bits on all platforms. Values of this type can range from 32,768 to 32,767.
typedef unsigned short guint16;
An unsigned integer guaranteed to be 16 bits on all platforms. Values of this type can range from 0 to 65,535.
typedef signed int gint32;
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.
typedef unsigned int guint32;
An unsigned integer guaranteed to be 32 bits on all platforms. Values of this type can range from 0 to 4,294,967,295.
#define G_HAVE_GINT64 1 /* deprecated, always true */
G_HAVE_GINT64
is deprecated and should not be used in newlywritten code. GLib requires 64bit integer support since version 2.0, therefore
G_HAVE_GINT64
is always defined.
This macro is defined if 64bit signed and unsigned integers are available on the platform.
G_GNUC_EXTENSION typedef signed long long gint64;
A signed integer guaranteed to be 64 bits on all platforms. Values of this type can range from 9,223,372,036,854,775,808 to 9,223,372,036,854,775,807.
GLIB_VAR guint64 ();
An unsigned integer guaranteed to be 64 bits on all platforms. Values of this type can range from 0 to 18,446,744,073,709,551,615.
Returns : 
#define G_GINT64_CONSTANT(val) (G_GNUC_EXTENSION (val##LL))
This macro is used to insert 64bit integer literals into the source code.

a literal integer value, e.g. 0x1d636b02300a7aa7U. 
#define G_GUINT64_CONSTANT(val) (G_GNUC_EXTENSION (val##ULL))
This macro is used to insert 64bit unsigned integer literals into the source code.

a literal integer value, e.g. 0x1d636b02300a7aa7U. 
Since 2.10
typedef float gfloat;
Corresponds to the standard C float type. Values of this type can range from G_MAXFLOAT to G_MAXFLOAT.
typedef double gdouble;
Corresponds to the standard C double type. Values of this type can range from G_MAXDOUBLE to G_MAXDOUBLE.
typedef unsigned int gsize;
An unsigned integer type of the result of the sizeof operator, corresponding to the size_t type defined in C99. This type is wide enough to hold the numeric value of a pointer, so it is usually 32bit wide on a 32bit platform and 64bit wide on a 64bit platform.
typedef signed int gssize;
A signed variant of gsize, corresponding to the ssize_t defined on most platforms.