8
These functions raise :exc:`TypeError` when expecting a bytes parameter and are
9
called with a non-bytes parameter.
11
.. index:: object: bytes
14
.. c:type:: PyBytesObject
16
This subtype of :c:type:`PyObject` represents a Python bytes object.
19
.. c:var:: PyTypeObject PyBytes_Type
21
This instance of :c:type:`PyTypeObject` represents the Python bytes type; it
22
is the same object as :class:`bytes` in the Python layer.
25
.. c:function:: int PyBytes_Check(PyObject *o)
27
Return true if the object *o* is a bytes object or an instance of a subtype
31
.. c:function:: int PyBytes_CheckExact(PyObject *o)
33
Return true if the object *o* is a bytes object, but not an instance of a
34
subtype of the bytes type.
37
.. c:function:: PyObject* PyBytes_FromString(const char *v)
39
Return a new bytes object with a copy of the string *v* as value on success,
40
and *NULL* on failure. The parameter *v* must not be *NULL*; it will not be
44
.. c:function:: PyObject* PyBytes_FromStringAndSize(const char *v, Py_ssize_t len)
46
Return a new bytes object with a copy of the string *v* as value and length
47
*len* on success, and *NULL* on failure. If *v* is *NULL*, the contents of
48
the bytes object are uninitialized.
51
.. c:function:: PyObject* PyBytes_FromFormat(const char *format, ...)
53
Take a C :c:func:`printf`\ -style *format* string and a variable number of
54
arguments, calculate the size of the resulting Python bytes object and return
55
a bytes object with the values formatted into it. The variable arguments
56
must be C types and must correspond exactly to the format characters in the
57
*format* string. The following format characters are allowed:
59
.. % XXX: This should be exactly the same as the table in PyErr_Format.
60
.. % One should just refer to the other.
61
.. % XXX: The descriptions for %zd and %zu are wrong, but the truth is complicated
62
.. % because not all compilers support the %z width modifier -- we fake it
63
.. % when necessary via interpolating PY_FORMAT_SIZE_T.
65
.. tabularcolumns:: |l|l|L|
67
+-------------------+---------------+--------------------------------+
68
| Format Characters | Type | Comment |
69
+===================+===============+================================+
70
| :attr:`%%` | *n/a* | The literal % character. |
71
+-------------------+---------------+--------------------------------+
72
| :attr:`%c` | int | A single character, |
73
| | | represented as an C int. |
74
+-------------------+---------------+--------------------------------+
75
| :attr:`%d` | int | Exactly equivalent to |
76
| | | ``printf("%d")``. |
77
+-------------------+---------------+--------------------------------+
78
| :attr:`%u` | unsigned int | Exactly equivalent to |
79
| | | ``printf("%u")``. |
80
+-------------------+---------------+--------------------------------+
81
| :attr:`%ld` | long | Exactly equivalent to |
82
| | | ``printf("%ld")``. |
83
+-------------------+---------------+--------------------------------+
84
| :attr:`%lu` | unsigned long | Exactly equivalent to |
85
| | | ``printf("%lu")``. |
86
+-------------------+---------------+--------------------------------+
87
| :attr:`%zd` | Py_ssize_t | Exactly equivalent to |
88
| | | ``printf("%zd")``. |
89
+-------------------+---------------+--------------------------------+
90
| :attr:`%zu` | size_t | Exactly equivalent to |
91
| | | ``printf("%zu")``. |
92
+-------------------+---------------+--------------------------------+
93
| :attr:`%i` | int | Exactly equivalent to |
94
| | | ``printf("%i")``. |
95
+-------------------+---------------+--------------------------------+
96
| :attr:`%x` | int | Exactly equivalent to |
97
| | | ``printf("%x")``. |
98
+-------------------+---------------+--------------------------------+
99
| :attr:`%s` | char\* | A null-terminated C character |
101
+-------------------+---------------+--------------------------------+
102
| :attr:`%p` | void\* | The hex representation of a C |
103
| | | pointer. Mostly equivalent to |
104
| | | ``printf("%p")`` except that |
105
| | | it is guaranteed to start with |
106
| | | the literal ``0x`` regardless |
107
| | | of what the platform's |
108
| | | ``printf`` yields. |
109
+-------------------+---------------+--------------------------------+
111
An unrecognized format character causes all the rest of the format string to be
112
copied as-is to the result string, and any extra arguments discarded.
115
.. c:function:: PyObject* PyBytes_FromFormatV(const char *format, va_list vargs)
117
Identical to :c:func:`PyBytes_FromFormat` except that it takes exactly two
121
.. c:function:: PyObject* PyBytes_FromObject(PyObject *o)
123
Return the bytes representation of object *o* that implements the buffer
127
.. c:function:: Py_ssize_t PyBytes_Size(PyObject *o)
129
Return the length of the bytes in bytes object *o*.
132
.. c:function:: Py_ssize_t PyBytes_GET_SIZE(PyObject *o)
134
Macro form of :c:func:`PyBytes_Size` but without error checking.
137
.. c:function:: char* PyBytes_AsString(PyObject *o)
139
Return a NUL-terminated representation of the contents of *o*. The pointer
140
refers to the internal buffer of *o*, not a copy. The data must not be
141
modified in any way, unless the string was just created using
142
``PyBytes_FromStringAndSize(NULL, size)``. It must not be deallocated. If
143
*o* is not a string object at all, :c:func:`PyBytes_AsString` returns *NULL*
144
and raises :exc:`TypeError`.
147
.. c:function:: char* PyBytes_AS_STRING(PyObject *string)
149
Macro form of :c:func:`PyBytes_AsString` but without error checking.
152
.. c:function:: int PyBytes_AsStringAndSize(PyObject *obj, char **buffer, Py_ssize_t *length)
154
Return a NUL-terminated representation of the contents of the object *obj*
155
through the output variables *buffer* and *length*.
157
If *length* is *NULL*, the resulting buffer may not contain NUL characters;
158
if it does, the function returns ``-1`` and a :exc:`TypeError` is raised.
160
The buffer refers to an internal string buffer of *obj*, not a copy. The data
161
must not be modified in any way, unless the string was just created using
162
``PyBytes_FromStringAndSize(NULL, size)``. It must not be deallocated. If
163
*string* is not a string object at all, :c:func:`PyBytes_AsStringAndSize`
164
returns ``-1`` and raises :exc:`TypeError`.
167
.. c:function:: void PyBytes_Concat(PyObject **bytes, PyObject *newpart)
169
Create a new bytes object in *\*bytes* containing the contents of *newpart*
170
appended to *bytes*; the caller will own the new reference. The reference to
171
the old value of *bytes* will be stolen. If the new string cannot be
172
created, the old reference to *bytes* will still be discarded and the value
173
of *\*bytes* will be set to *NULL*; the appropriate exception will be set.
176
.. c:function:: void PyBytes_ConcatAndDel(PyObject **bytes, PyObject *newpart)
178
Create a new string object in *\*bytes* containing the contents of *newpart*
179
appended to *bytes*. This version decrements the reference count of
183
.. c:function:: int _PyBytes_Resize(PyObject **bytes, Py_ssize_t newsize)
185
A way to resize a bytes object even though it is "immutable". Only use this
186
to build up a brand new bytes object; don't use this if the bytes may already
187
be known in other parts of the code. It is an error to call this function if
188
the refcount on the input bytes object is not one. Pass the address of an
189
existing bytes object as an lvalue (it may be written into), and the new size
190
desired. On success, *\*bytes* holds the resized bytes object and ``0`` is
191
returned; the address in *\*bytes* may differ from its input value. If the
192
reallocation fails, the original bytes object at *\*bytes* is deallocated,
193
*\*bytes* is set to *NULL*, a memory exception is set, and ``-1`` is