g_array_new ()

GArray *
g_array_new (gboolean zero_terminated,
             gboolean clear_,
             guint element_size);

Creates a new GArray with a reference count of 1.

g_array_steal ()

gpointer
g_array_steal (GArray *array,
               gsize *len);

Frees the data in the array and resets the size to zero, while the underlying array is preserved for use elsewhere and returned to the caller.

If the array was created with the zero_terminate property set to TRUE, the returned data is zero terminated too.

If array elements contain dynamically-allocated memory, the array elements should also be freed by the caller.

A short example of use:

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...
gpointer data;
gsize data_len;
data = g_array_steal (some_array, &data_len);
...

Since: 2.64

g_array_sized_new ()

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 and a reference count of 1. 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.

g_array_copy ()

GArray *
g_array_copy (GArray *array);

Create a shallow copy of a GArray. If the array elements consist of pointers to data, the pointers are copied but the actual data is not.

Since: 2.62

g_array_ref ()

GArray *
g_array_ref (GArray *array);

Atomically increments the reference count of array by one. This function is thread-safe and may be called from any thread.

Since: 2.22

g_array_unref ()

void
g_array_unref (GArray *array);

Atomically decrements the reference count of array by one. If the reference count drops to 0, all memory allocated by the array is released. This function is thread-safe and may be called from any thread.

Since: 2.22

g_array_get_element_size ()

guint
g_array_get_element_size (GArray *array);

Gets the size of the elements in array .

Since: 2.22

g_array_append_val()

#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.

g_array_append_vals ()

GArray *
g_array_append_vals (GArray *array,
                     gconstpointer data,
                     guint len);

Adds len elements onto the end of the array.

g_array_prepend_val()

#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.

g_array_prepend_vals ()

GArray *
g_array_prepend_vals (GArray *array,
                      gconstpointer data,
                      guint len);

Adds len elements onto the start of the array.

data may be NULL if (and only if) len is zero. If len is zero, this function is a no-op.

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.

g_array_insert_val()

#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.

g_array_insert_vals ()

GArray *
g_array_insert_vals (GArray *array,
                     guint index_,
                     gconstpointer data,
                     guint len);

Inserts len elements into a GArray at the given index.

If index_ is greater than the array’s current length, the array is expanded. The elements between the old end of the array and the newly inserted elements will be initialised to zero if the array was configured to clear elements; otherwise their values will be undefined.

If index_ is less than the array’s current length, new entries will be inserted into the array, and the existing entries above index_ will be moved upwards.

data may be NULL if (and only if) len is zero. If len is zero, this function is a no-op.

g_array_remove_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.

g_array_remove_index_fast ()

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().

g_array_remove_range ()

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.

Since: 2.4

g_array_sort ()

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).

This is guaranteed to be a stable sort since version 2.32.

g_array_sort_with_data ()

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.

This is guaranteed to be a stable sort since version 2.32.

There used to be a comment here about making the sort stable by using the addresses of the elements in the comparison function. This did not actually work, so any such code should be removed.

g_array_binary_search ()

gboolean
g_array_binary_search (GArray *array,
                       gconstpointer target,
                       GCompareFunc compare_func,
                       guint *out_match_index);

Checks whether target exists in array by performing a binary search based on the given comparison function compare_func which get pointers to items as arguments. If the element is found, TRUE is returned and the element’s index is returned in out_match_index (if non-NULL). Otherwise, FALSE is returned and out_match_index is undefined. If target exists multiple times in array , the index of the first instance is returned. This search is using a binary search, so the array must absolutely be sorted to return a correct result (if not, the function may produce false-negative).

This example defines a comparison function and search an element in a GArray:

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static gint*
cmpint (gconstpointer a, gconstpointer b)
{
  const gint *_a = a;
  const gint *_b = b;

  return *_a - *_b;
}
...
gint i = 424242;
guint matched_index;
gboolean result = g_array_binary_search (garray, &i, cmpint, &matched_index);
...

Since: 2.62

g_array_index()

#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. This is the main way to read or write an element in a GArray.

Writing an element is typically done by reference, as in the following example. This example gets a pointer to an element in a GArray, and then writes to a field in it:

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EDayViewEvent *event;
// This gets a pointer to the 4th element in the array of
// EDayViewEvent structs.
event = &g_array_index (events, EDayViewEvent, 3);
event->start_time = g_get_current_time ();

This example reads from and writes to an array of integers:

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g_autoptr(GArray) int_array = g_array_new (FALSE, FALSE, sizeof (guint));
for (guint i = 0; i < 10; i++)
  g_array_append_val (int_array, i);

guint *my_int = &g_array_index (int_array, guint, 1);
g_print ("Int at index 1 is %u; decrementing it\n", *my_int);
*my_int = *my_int - 1;

g_array_set_size ()

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.

g_array_set_clear_func ()

void
g_array_set_clear_func (GArray *array,
                        GDestroyNotify clear_func);

Sets a function to clear an element of array .

The clear_func will be called when an element in the array data segment is removed and when the array is freed and data segment is deallocated as well. clear_func will be passed a pointer to the element to clear, rather than the element itself.

Note that in contrast with other uses of GDestroyNotify functions, clear_func is expected to clear the contents of the array element it is given, but not free the element itself.

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typedef struct
{
  gchar *str;
  GObject *obj;
} ArrayElement;

static void
array_element_clear (ArrayElement *element)
{
  g_clear_pointer (&element->str, g_free);
  g_clear_object (&element->obj);
}

// main code
GArray *garray = g_array_new (FALSE, FALSE, sizeof (ArrayElement));
g_array_set_clear_func (garray, (GDestroyNotify) array_element_clear);
// assign data to the structure
g_array_free (garray, TRUE);

Since: 2.32

g_array_free ()

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 the reference count of array is greater than one, the GArray wrapper is preserved but the size of array will be set to zero.

If array contents point to dynamically-allocated memory, they should be freed separately if free_seg is TRUE and no clear_func function has been set for array .

This function is not thread-safe. If using a GArray from multiple threads, use only the atomic g_array_ref() and g_array_unref() functions.

struct GArray

struct GArray {
  gchar *data;
  guint len;
};

Contains the public fields of a GArray.