arrays_byte.sgml

GLib是GTK+和GNOME工程的基础底层核心程序库

<!-- ##### SECTION Title ##### -->
Byte Arrays

<!-- ##### SECTION Short_Description ##### -->
arrays of bytes, which grow automatically as elements are added.

<!-- ##### SECTION Long_Description ##### -->
<para>
#GByteArray is based on #GArray, to provide arrays of bytes which grow
automatically as elements are added.
</para>
<para>
To create a new #GByteArray use g_byte_array_new().
</para>
<para>
To add elements to a #GByteArray, use g_byte_array_append(), and
g_byte_array_prepend().
</para>
<para>
To set the size of a #GByteArray, use g_byte_array_set_size().
</para>
<para>
To free a #GByteArray, use g_byte_array_free().
</para>

<example>
<title>Using a <structname>GByteArray</structname>.</title>
<programlisting>
  GByteArray *gbarray;
  gint i;

  gbarray = g_byte_array_new (<!>);
  for (i = 0; i < 10000; i++)
    g_byte_array_append (gbarray, (guint8*) "abcd", 4);

  for (i = 0; i < 10000; i++)
    {
      g_assert (gbarray->data[4*i] == 'a');
      g_assert (gbarray->data[4*i+1] == 'b');
      g_assert (gbarray->data[4*i+2] == 'c');
      g_assert (gbarray->data[4*i+3] == 'd');
    }

  g_byte_array_free (gbarray, TRUE);
</programlisting></example>

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

</para>

<!-- ##### STRUCT GByteArray ##### -->
<para>
The <structname>GByteArray</structname> struct allows access to the public fields of a <structname>GByteArray</structname>.
</para>

@data: a pointer to the element data. The data may be moved as elements are
added to the #GByteArray.
@len: the number of elements in the #GByteArray.

<!-- ##### FUNCTION g_byte_array_new ##### -->
<para>
Creates a new #GByteArray.
</para>

@Returns: the new #GByteArray.


<!-- ##### FUNCTION g_byte_array_sized_new ##### -->
<para>
Creates a new #GByteArray with @reserved_size bytes preallocated. This
avoids frequent reallocation, if you are going to add many bytes to
the array. Note however that the size of the array is still 0.
</para>

@reserved_size: number of bytes preallocated.
@Returns: the new #GByteArray.


<!-- ##### FUNCTION g_byte_array_append ##### -->
<para>
Adds the given bytes to the end of the #GByteArray.
The array will grow in size automatically if necessary.
</para>

@array: a #GByteArray.
@data: the byte data to be added.
@len: the number of bytes to add.
@Returns: the #GByteArray.


<!-- ##### FUNCTION g_byte_array_prepend ##### -->
<para>
Adds the given data to the start of the #GByteArray.
The array will grow in size automatically if necessary.
</para>

@array: a #GByteArray.
@data: the byte data to be added.
@len: the number of bytes to add.
@Returns: the #GByteArray.


<!-- ##### FUNCTION g_byte_array_remove_index ##### -->
<para>
Removes the byte at the given index from a #GByteArray.
The following bytes are moved down one place.
</para>

@array: a #GByteArray.
@index: the index of the byte to remove.
@Returns: the #GByteArray.


<!-- ##### FUNCTION g_byte_array_remove_index_fast ##### -->
<para>
Removes the byte at the given index from a #GByteArray.
The last element in the array is used to fill in the space, so this function
does not preserve the order of the #GByteArray. But it is faster than
g_byte_array_remove_index().
</para>

@array: a #GByteArray.
@index: the index of the byte to remove.
@Returns: the #GByteArray.


<!-- ##### FUNCTION g_byte_array_sort ##### -->
<para>
Sorts a byte array, using @compare_func which should be a <function>qsort()</function>-style
comparison function (returns -1 for first arg is less than second arg, 0 for
equal, 1 if first arg is greater than second arg).
</para>

@array: a #GByteArray.
@compare_func: comparison function.


<!-- ##### FUNCTION g_byte_array_sort_with_data ##### -->
<para>
Like g_byte_array_sort(), but the comparison function takes a user data argument.
</para>

@array: a #GByteArray.
@compare_func: comparison function.
@user_data: data to pass to @compare_func.


<!-- ##### FUNCTION g_byte_array_set_size ##### -->
<para>
Sets the size of the #GByteArray, expanding it if necessary.
</para>

@array: a #GByteArray.
@length: the new size of the #GByteArray.
@Returns: the #GByteArray.


<!-- ##### FUNCTION g_byte_array_free ##### -->
<para>
Frees the memory allocated by the #GByteArray.
If @free_segment is %TRUE it frees the actual byte data.
</para>

@array: a #GByteArray.
@free_segment: if %TRUE the actual byte data is freed as well.
@Returns: