Objets fichiers

Python’s built-in file objects are implemented entirely on the FILE* support from the C standard library. This is an implementation detail and may change in future releases of Python.

PyFileObject

This subtype of PyObject represents a Python file object.

PyTypeObject PyFile_Type

This instance of PyTypeObject represents the Python file type. This is exposed to Python programs as file and types.FileType.

int PyFile_Check(PyObject *p)

Return true if its argument is a PyFileObject or a subtype of PyFileObject.

Modifié dans la version 2.2: Allowed subtypes to be accepted.

int PyFile_CheckExact(PyObject *p)

Return true if its argument is a PyFileObject, but not a subtype of PyFileObject.

Nouveau dans la version 2.2.

PyObject* PyFile_FromString(char *filename, char *mode)
Return value: New reference.

On success, return a new file object that is opened on the file given by filename, with a file mode given by mode, where mode has the same semantics as the standard C routine fopen(). On failure, return NULL.

PyObject* PyFile_FromFile(FILE *fp, char *name, char *mode, int (*close)(FILE*))
Return value: New reference.

Create a new PyFileObject from the already-open standard C file pointer, fp. The function close will be called when the file should be closed. Return NULL and close the file using close on failure. close is optional and can be set to NULL.

FILE* PyFile_AsFile(PyObject *p)

Return the file object associated with p as a FILE*.

If the caller will ever use the returned FILE* object while the GIL is released it must also call the PyFile_IncUseCount() and PyFile_DecUseCount() functions described below as appropriate.

void PyFile_IncUseCount(PyFileObject *p)

Increments the PyFileObject’s internal use count to indicate that the underlying FILE* is being used. This prevents Python from calling f_close() on it from another thread. Callers of this must call PyFile_DecUseCount() when they are finished with the FILE*. Otherwise the file object will never be closed by Python.

The GIL must be held while calling this function.

The suggested use is to call this after PyFile_AsFile() and before you release the GIL:

FILE *fp = PyFile_AsFile(p);
PyFile_IncUseCount(p);
/* ... */
Py_BEGIN_ALLOW_THREADS
do_something(fp);
Py_END_ALLOW_THREADS
/* ... */
PyFile_DecUseCount(p);

Nouveau dans la version 2.6.

void PyFile_DecUseCount(PyFileObject *p)

Decrements the PyFileObject’s internal unlocked_count member to indicate that the caller is done with its own use of the FILE*. This may only be called to undo a prior call to PyFile_IncUseCount().

The GIL must be held while calling this function (see the example above).

Nouveau dans la version 2.6.

PyObject* PyFile_GetLine(PyObject *p, int n)
Return value: New reference.

Cette fonction, équivalente à p.readline([n]), lit une ligne de l’objet p. p peut être un objet fichier ou n’importe quel objet qui possède une méthode readline(). Si n vaut 0, une seule ligne est lue, indépendamment de la taille de la ligne. Si n est plus grand que 0, un maximum de n octets seront lus en provenance du fichier ; une ligne partielle peut être renvoyée. Dans les deux cas, une chaîne de caractères vide est renvoyée si la fin du fichier est atteinte immédiatement. Cependant, si n est plus petit que 0, une ligne est lue indépendamment de sa taille, mais EOFError est levée si la fin du fichier est atteinte immédiatement.

PyObject* PyFile_Name(PyObject *p)
Return value: Borrowed reference.

Return the name of the file specified by p as a string object.

void PyFile_SetBufSize(PyFileObject *p, int n)

Available on systems with setvbuf() only. This should only be called immediately after file object creation.

int PyFile_SetEncoding(PyFileObject *p, const char *enc)

Set the file’s encoding for Unicode output to enc. Return 1 on success and 0 on failure.

Nouveau dans la version 2.3.

int PyFile_SetEncodingAndErrors(PyFileObject *p, const char *enc, *errors)

Set the file’s encoding for Unicode output to enc, and its error mode to err. Return 1 on success and 0 on failure.

Nouveau dans la version 2.6.

int PyFile_SoftSpace(PyObject *p, int newflag)

This function exists for internal use by the interpreter. Set the softspace attribute of p to newflag and return the previous value. p does not have to be a file object for this function to work properly; any object is supported (thought its only interesting if the softspace attribute can be set). This function clears any errors, and will return 0 as the previous value if the attribute either does not exist or if there were errors in retrieving it. There is no way to detect errors from this function, but doing so should not be needed.

int PyFile_WriteObject(PyObject *obj, PyObject *p, int flags)

Écrit l’objet obj dans l’objet fichier p. La seule option gérée pour flags est Py_PRINT_RAW ; si défini, l’attribut str() de l’objet est écrit à la place de l’attribut repr(). Retourne 0 en cas de succès ou -1 en cas échec ; l’exception appropriée sera levée.

int PyFile_WriteString(const char *s, PyObject *p)

Écrit la chaîne de caractères s dans l’objet fichier p. Retourne 0 en cas de succès ou -1 en cas d’échec ; l’exception appropriée sera mise en place.