Standard Macros
commonly-used macros.
These macros provide a few commonly-used features.
The major version number of the GLib library.
The minor version number of the GLib library.
The micro version number of the GLib library.
This macro is defined only on Windows. So you can bracket
Windows-specific code in "#ifdef G_OS_WIN32".
This macro is defined only on BeOS. So you can bracket
BeOS-specific code in "#ifdef G_OS_BEOS".
This macro is defined only on UNIX. So you can bracket
UNIX-specific code in "#ifdef G_OS_UNIX".
Checks the version of the GLib library.
It returns %TRUE if the GLib library is the same or newer than the given
version.
Checking the version of the GLib library
if (!GLIB_CHECK_VERSION (1, 2, 0))
g_error ("GLib version 1.2.0 or above is needed");
@major: the major version number.
@minor: the minor version number.
@micro: the micro version number.
The directory separator character.
This is '/' on UNIX machines and '\' under Windows.
The directory separator as a string.
This is "/" on UNIX machines and "\" under Windows.
The search path separator character.
This is ':' on UNIX machines and ';' under Windows.
The search path separator as a string.
This is ":" on UNIX machines and ";" under Windows.
Defines the %TRUE value for the #gboolean type.
Defines the %FALSE value for the #gboolean type.
Defines the standard %NULL pointer.
Calculates the minimum of @a and @b.
@a: a numeric value.
@b: a numeric value.
@Returns: the minimum of @a and @b.
Calculates the maximum of @a and @b.
@a: a numeric value.
@b: a numeric value.
@Returns: the maximum of @a and @b.
Calculates the absolute value of @a.
The absolute value is simply the number with any negative sign taken away.
For example,
ABS(-10) is 10.
ABS(10) is also 10.
@a: a numeric value.
@Returns: the absolute value of @a.
Ensures that @x is between the limits set by @low and @high.
For example,
CLAMP(5, 10, 15) is 10.
CLAMP(15, 5, 10) is 10.
CLAMP(20, 15, 25) is 20.
@x: the value to clamp.
@low: the minimum value allowed.
@high: the maximum value allowed.
@Returns: the value of @x clamped to the range between @low and @high.
Returns a member of a structure at a given offset, using the given type.
@member_type: the type of the struct field.
@struct_p: a pointer to a struct.
@struct_offset: the offset of the field from the start of the struct, in bytes.
@Returns: the struct member.
Returns an untyped pointer to a given offset of a struct.
@struct_p: a pointer to a struct.
@struct_offset: the offset from the start of the struct, in bytes.
@Returns: an untyped pointer to @struct_p plus @struct_offset bytes.
Returns the offset, in bytes, of a member of a struct.
@struct_type: a structure type, e.g. GtkWidget.
@member: a field in the structure, e.g. window.
@Returns: the offset of @member from the start of @struct_type.
Indicates the number of bytes to which memory will be aligned on the
current platform.
If %G_DISABLE_CONST_RETURNS is defined, this macro expands to nothing.
By default, the macro expands to const. The macro
should be used in place of const for functions that
return a value that should not be modified. The purpose of this macro is
to allow us to turn on const for returned constant
strings by default, while allowing programmers who find that annoying to
turn it off. This macro should only be used for return values and for
out parameters, it doesn't make sense for
in parameters.