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GLib Reference Manual | |
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#include <glib.h>
GArray;
GArray* g_array_new (gboolean zero_terminated,
gboolean clear_,
guint element_size);
GArray* g_array_sized_new (gboolean zero_terminated,
gboolean clear_,
guint element_size,
guint reserved_size);
#define g_array_append_val (a,v)
GArray* g_array_append_vals (GArray *array,
gconstpointer data,
guint len);
#define g_array_prepend_val (a,v)
GArray* g_array_prepend_vals (GArray *array,
gconstpointer data,
guint len);
#define g_array_insert_val (a,i,v)
GArray* g_array_insert_vals (GArray *array,
guint index_,
gconstpointer data,
guint len);
GArray* g_array_remove_index (GArray *array,
guint index_);
GArray* g_array_remove_index_fast (GArray *array,
guint index_);
GArray* g_array_remove_range (GArray *array,
guint index_,
guint length);
void g_array_sort (GArray *array,
GCompareFunc compare_func);
void g_array_sort_with_data (GArray *array,
GCompareDataFunc compare_func,
gpointer user_data);
#define g_array_index (a,t,i)
GArray* g_array_set_size (GArray *array,
guint length);
gchar* g_array_free (GArray *array,
gboolean free_segment);
Arrays are similar to standard C arrays, except that they grow automatically as elements are added.
Array elements can be of any size (though all elements of one array are the same size), and the array can be automatically cleared to '0's and zero-terminated.
To create a new array use g_array_new().
To add elements to an array, use g_array_append_val(), g_array_append_vals(),
g_array_prepend_val(), and g_array_prepend_vals().
To access an element of an array, use g_array_index().
To set the size of an array, use g_array_set_size().
To free an array, use g_array_free().
Example 19. Using a GArray to store gint values
GArray *garray;
gint i;
/* We create a new array to store gint values.
We don't want it zero-terminated or cleared to 0's. */
garray = g_array_new (FALSE, FALSE, sizeof (gint));
for (i = 0; i < 10000; i++)
g_array_append_val (garray, i);
for (i = 0; i < 10000; i++)
if (g_array_index (garray, gint, i) != i)
g_print ("ERROR: got %d instead of %d\n",
g_array_index (garray, gint, i), i);
g_array_free (garray, TRUE);
GArray* g_array_new (gboolean zero_terminated, gboolean clear_, guint element_size);
Creates a new GArray.
GArray* g_array_sized_new (gboolean zero_terminated, gboolean clear_, guint element_size, guint reserved_size);
Creates a new GArray with reserved_size elements
preallocated. This avoids frequent reallocation, if you are going to
add many elements to the array. Note however that the size of the
array is still 0.
zero_terminated : |
TRUE if the array should have an extra element at the end with all bits cleared.
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clear_ : |
TRUE if all bits in the array should be cleared to 0 on allocation.
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element_size : |
size of each element in the array. |
reserved_size : |
number of elements preallocated. |
| Returns : | the new GArray. |
#define g_array_append_val(a,v)
Adds the value on to the end of the array. The array will grow in size automatically if necessary.
g_array_append_val() is a macro which uses a reference to the value
parameter v. This means that you cannot use it with literal values
such as "27". You must use variables.
GArray* g_array_append_vals (GArray *array, gconstpointer data, guint len);
Adds len elements onto the end of the array.
#define g_array_prepend_val(a,v)
Adds the value on to the start of the array. The array will grow in size automatically if necessary.
This operation is slower than g_array_append_val() since the existing elements
in the array have to be moved to make space for the new element.
g_array_prepend_val() is a macro which uses a reference to the value
parameter v. This means that you cannot use it with literal values
such as "27". You must use variables.
GArray* g_array_prepend_vals (GArray *array, gconstpointer data, guint len);
Adds len elements onto the start of the array.
This operation is slower than g_array_append_vals() since the existing elements
in the array have to be moved to make space for the new elements.
#define g_array_insert_val(a,i,v)
Inserts an element into an array at the given index.
g_array_insert_val() is a macro which uses a reference to the value
parameter v. This means that you cannot use it with literal values
such as "27". You must use variables.
GArray* g_array_insert_vals (GArray *array, guint index_, gconstpointer data, guint len);
Inserts len elements into a GArray at the given index.
GArray* g_array_remove_index (GArray *array, guint index_);
Removes the element at the given index from a GArray. The following elements are moved down one place.
GArray* g_array_remove_index_fast (GArray *array, guint index_);
Removes the element at the given index from a GArray.
The last element in the array is used to fill in the space, so this function
does not preserve the order of the GArray. But it is faster than
g_array_remove_index().
array : |
a GArray.
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index_ : |
the index of the element to remove. |
| Returns : | the GArray. |
GArray* g_array_remove_range (GArray *array, guint index_, guint length);
Removes the given number of elements starting at the given index from a GArray. The following elements are moved to close the gap.
array : |
a GArray.
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index_ : |
the index of the first element to remove. |
length : |
the number of elements to remove. |
| Returns : | the GArray. |
Since 2.4
void g_array_sort (GArray *array, GCompareFunc compare_func);
Sorts a GArray using compare_func which should be a qsort()-style comparison
function (returns less than zero for first arg is less than second arg,
zero for equal, greater zero if first arg is greater than second arg).
If two array elements compare equal, their order in the sorted array is undefined.
array : |
a GArray. |
compare_func : |
comparison function. |
void g_array_sort_with_data (GArray *array, GCompareDataFunc compare_func, gpointer user_data);
Like g_array_sort(), but the comparison function receives an extra user data
argument.
array : |
a GArray. |
compare_func : |
comparison function. |
user_data : |
data to pass to compare_func.
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#define g_array_index(a,t,i)
Returns the element of a GArray at the given index. The return value is cast to the given type.
Example 20. Getting a pointer to an element in a GArray
EDayViewEvent *event;
/* This gets a pointer to the 4th element in the array of EDayViewEvent
structs. */
event = &g_array_index (events, EDayViewEvent, 3);
GArray* g_array_set_size (GArray *array, guint length);
Sets the size of the array, expanding it if necessary.
If the array was created with clear_ set to TRUE, the new elements are set to 0.
gchar* g_array_free (GArray *array, gboolean free_segment);
Frees the memory allocated for the GArray.
If free_segment is TRUE it frees the memory block holding the elements
as well. Pass FALSE if you want to free the GArray wrapper but preserve
the underlying array for use elsewhere.
If array elements contain dynamically-allocated memory, they should be freed separately.