异常处理

The functions described in this chapter will let you handle and raise Python exceptions. It is important to understand some of the basics of Python exception handling. It works somewhat like the Unix errno variable: there is a global indicator (per thread) of the last error that occurred. Most functions don’t clear this on success, but will set it to indicate the cause of the error on failure. Most functions also return an error indicator, usually NULL 若假设它们要返回指针,或者 -1 若它们返回整数 (例外: PyArg_*() 函数返回 1 对于成功和 0 对于故障)。

当函数因调用的某个函数失败而必须失败时,一般不设置错误指示器;它调用的函数已有设置。它负责处理错误和清零异常或在清理它保持的任何资源后返回 (譬如:对象引用或内存分配);它应该 not 继续通常,若不准备处理错误。若由于错误而返回,重要的是向调用者指示有设置错误。若错误未被处理或被小心谨慎地传播,对 Python/C API 的额外调用可能没有如打算般的行为,且可能以神秘方式失败。

The error indicator consists of three Python objects corresponding to the result of sys.exc_info() . API functions exist to interact with the error indicator in various ways. There is a separate error indicator for each thread.

void PyErr_PrintEx ( int  set_sys_last_vars )

将标准回溯打印到 sys.stderr 并清零错误指示器。仅当错误指示器有设置时才调用此函数。(否则会导致致命错误!)

set_sys_last_vars 非 0,变量 sys.last_type , sys.last_value and sys.last_traceback 将被分别设为打印异常的类型、值及回溯。

void PyErr_Print ( )

别名化的 PyErr_PrintEx(1) .

PyObject * PyErr_Occurred ( )
返回值:借位引用。

测试是否有设置错误指示器。若有设置,返回异常 type (首自变量到最后一次调用的一 PyErr_Set*() 函数或到 PyErr_Restore() )。若未设置,返回 NULL 。不拥有对返回值的引用,因此不需要 Py_DECREF() 它。

注意

不要将返回值与特定异常进行比较;使用 PyErr_ExceptionMatches() 代替,如下所示。(比较可能很易失败,因为异常可能是实例而不是类,在类异常的情况下,或它可能是期望异常的子类。)

int PyErr_ExceptionMatches ( PyObject  *exc )

相当于 PyErr_GivenExceptionMatches(PyErr_Occurred(), exc) 。这才应该被调用当有实际设置异常时;会发生内存访问违反若没有引发异常。

int PyErr_GivenExceptionMatches ( PyObject  *given , PyObject  *exc )

返回 True 若 given exception matches the exception in exc 。若 exc 是类对象,这还返回 True 当 given 是子类的实例。若 exc is a tuple, all exceptions in the tuple (and recursively in subtuples) are searched for a match.

void PyErr_NormalizeException ( PyObject **exc, PyObject **val, PyObject **tb )

在某些情况下,值的返回通过 PyErr_Fetch() below can be “unnormalized”, meaning that *exc 是类对象但 *val is not an instance of the same class. This function can be used to instantiate the class in that case. If the values are already normalized, nothing happens. The delayed normalization is implemented to improve performance.

注意

This function does not implicitly set the __traceback__ attribute on the exception value. If setting the traceback appropriately is desired, the following additional snippet is needed:

if (tb != NULL) {
  PyException_SetTraceback(val, tb);
}
							
void PyErr_Clear ( )

清零错误指示器。若未设置错误指示器,则没有效果。

void PyErr_Fetch ( PyObject  **ptype , PyObject  **pvalue , PyObject  **ptraceback )

Retrieve the error indicator into three variables whose addresses are passed. If the error indicator is not set, set all three variables to NULL . If it is set, it will be cleared and you own a reference to each object retrieved. The value and traceback object may be NULL even when the type object is not.

注意

This function is normally only used by code that needs to handle exceptions or by code that needs to save and restore the error indicator temporarily.

void PyErr_Restore ( PyObject  *type , PyObject  *value , PyObject  *traceback )

Set the error indicator from the three objects. If the error indicator is already set, it is cleared first. If the objects are NULL , the error indicator is cleared. Do not pass a NULL type and non- NULL value or traceback. The exception type should be a class. Do not pass an invalid exception type or value. (Violating these rules will cause subtle problems later.) This call takes away a reference to each object: you must own a reference to each object before the call and after the call you no longer own these references. (If you don’t understand this, don’t use this function. I warned you.)

注意

This function is normally only used by code that needs to save and restore the error indicator temporarily; use PyErr_Fetch() to save the current exception state.

void PyErr_GetExcInfo ( PyObject  **ptype , PyObject  **pvalue , PyObject  **ptraceback )

检索异常信息,已知来自 sys.exc_info() . This refers to an exception that was already caught, not to an exception that was freshly raised. Returns new references for the three objects, any of which may be NULL 。不修改异常信息状态。

注意

This function is not normally used by code that wants to handle exceptions. Rather, it can be used when code needs to save and restore the exception state temporarily. Use PyErr_SetExcInfo() to restore or clear the exception state.

3.3 版新增。

void PyErr_SetExcInfo ( PyObject  *type , PyObject  *value , PyObject  *traceback )

设置异常信息,作为已知来自 sys.exc_info() . This refers to an exception that was already caught, not to an exception that was freshly raised. This function steals the references of the arguments. To clear the exception state, pass NULL for all three arguments. For general rules about the three arguments, see PyErr_Restore() .

注意

This function is not normally used by code that wants to handle exceptions. Rather, it can be used when code needs to save and restore the exception state temporarily. Use PyErr_GetExcInfo() to read the exception state.

3.3 版新增。

void PyErr_SetString ( PyObject  *type , const char  *message )

这是设置错误指示器的最常见方式。首个自变量指定异常类型;它通常是标准异常之一,如 PyExc_RuntimeError 。不需要递增其引用计数。第 2 自变量是错误信息;解码自 'utf-8 ‘.

void PyErr_SetObject ( PyObject  *type , PyObject  *value )

此函数类似于 PyErr_SetString() 但允许您为异常值指定任意 Python 对象。

PyObject * PyErr_Format ( PyObject  *exception , const char  *format , ... )
返回值:始终 NULL。

此函数设置错误指示器并返回 NULL . exception 应该是 Python 异常类。 format 和后续参数帮助格式化错误消息;它们拥有相同的意义和值如在 PyUnicode_FromFormat() . format 是 ASCII 编码字符串。

void PyErr_SetNone ( PyObject  *type )

这是简写的 PyErr_SetObject(type, Py_None) .

int PyErr_BadArgument ( )

这是简写的 PyErr_SetString(PyExc_TypeError, message) ,其中 message indicates that a built-in operation was invoked with an illegal argument. It is mostly for internal use.

PyObject * PyErr_NoMemory ( )
返回值:始终 NULL。

这是简写的 PyErr_SetNone(PyExc_MemoryError) ;它返回 NULL 因此对象分配函数可以写 return PyErr_NoMemory(); 当耗尽内存时。

PyObject * PyErr_SetFromErrno ( PyObject  *type )
返回值:始终 NULL。

这是方便函数以当 C 库函数返回错误时引发异常和设置 C 变量 errno . It constructs a tuple object whose first item is the integer errno value and whose second item is the corresponding error message (gotten from strerror() ), and then calls PyErr_SetObject(type, object) . On Unix, when the errno value is EINTR , indicating an interrupted system call, this calls PyErr_CheckSignals() , and if that set the error indicator, leaves it set to that. The function always returns NULL , so a wrapper function around a system call can write return PyErr_SetFromErrno(type); when the system call returns an error.

PyObject * PyErr_SetFromErrnoWithFilenameObject ( PyObject  *type , PyObject  *filenameObject )

类似于 PyErr_SetFromErrno() , with the additional behavior that if filenameObject 不是 NULL , it is passed to the constructor of type as a third parameter. In the case of OSError exception, this is used to define the filename attribute of the exception instance.

PyObject * PyErr_SetFromErrnoWithFilenameObjects ( PyObject  *type , PyObject  *filenameObject , PyObject  *filenameObject2 )

类似于 PyErr_SetFromErrnoWithFilenameObject() , but takes a second filename object, for raising errors when a function that takes two filenames fails.

3.4 版新增。

PyObject * PyErr_SetFromErrnoWithFilename ( PyObject  *type , const char  *filename )
返回值:始终 NULL。

类似于 PyErr_SetFromErrnoWithFilenameObject() , but the filename is given as a C string. filename is decoded from the filesystem encoding ( os.fsdecode() ).

PyObject * PyErr_SetFromWindowsErr ( int  ierr )
返回值:始终 NULL。

这是方便函数以引发 WindowsError . If called with ierr of 0 , the error code returned by a call to GetLastError() is used instead. It calls the Win32 function FormatMessage() to retrieve the Windows description of error code given by ierr or GetLastError() , then it constructs a tuple object whose first item is the ierr value and whose second item is the corresponding error message (gotten from FormatMessage() ), and then calls PyErr_SetObject(PyExc_WindowsError, object) . This function always returns NULL . Availability: Windows.

PyObject * PyErr_SetExcFromWindowsErr ( PyObject  *type , int  ierr )
返回值:始终 NULL。

类似于 PyErr_SetFromWindowsErr() , with an additional parameter specifying the exception type to be raised. Availability: Windows.

PyObject * PyErr_SetFromWindowsErrWithFilename ( int  ierr , const char  *filename )
返回值:始终 NULL。

类似于 PyErr_SetFromWindowsErrWithFilenameObject() , but the filename is given as a C string. filename is decoded from the filesystem encoding ( os.fsdecode() ). Availability: Windows.

PyObject * PyErr_SetExcFromWindowsErrWithFilenameObject ( PyObject  *type , int  ierr , PyObject  *filename )

类似于 PyErr_SetFromWindowsErrWithFilenameObject() , with an additional parameter specifying the exception type to be raised. Availability: Windows.

PyObject * PyErr_SetExcFromWindowsErrWithFilenameObjects ( PyObject  *type , int  ierr , PyObject  *filename , PyObject  *filename2 )

类似于 PyErr_SetExcFromWindowsErrWithFilenameObject() ,但接受第 2 文件名对象。可用性:Windows。

3.4 版新增。

PyObject * PyErr_SetExcFromWindowsErrWithFilename ( PyObject  *type , int  ierr , const char  *filename )
返回值:始终 NULL。

类似于 PyErr_SetFromWindowsErrWithFilename() , with an additional parameter specifying the exception type to be raised. Availability: Windows.

PyObject * PyErr_SetImportError ( PyObject  *msg , PyObject  *name , PyObject  *path )

这是方便函数以引发 ImportError . msg will be set as the exception’s message string. name and path , both of which can be NULL , will be set as the ImportError ‘s respective name and path 属性。

3.3 版新增。

void PyErr_SyntaxLocationObject ( PyObject  *filename , int  lineno , int  col_offset )

Set file, line, and offset information for the current exception. If the current exception is not a SyntaxError , then it sets additional attributes, which make the exception printing subsystem think the exception is a SyntaxError .

3.4 版新增。

void PyErr_SyntaxLocationEx ( const char  *filename , int  lineno , int  col_offset )

PyErr_SyntaxLocationObject() ,但 filename is a byte string decoded from the filesystem encoding ( os.fsdecode() ).

3.2 版新增。

void PyErr_SyntaxLocation ( const char  *filename , int  lineno )

PyErr_SyntaxLocationEx() ,但省略 col_offset 参数。

void PyErr_BadInternalCall ( )

这是简写的 PyErr_SetString(PyExc_SystemError, message) ,其中 message indicates that an internal operation (e.g. a Python/C API function) was invoked with an illegal argument. It is mostly for internal use.

int PyErr_WarnEx ( PyObject  *category , const char  *message , Py_ssize_t  stack_level )

Issue a warning message. The category argument is a warning category (see below) or NULL message argument is an UTF-8 encoded string. stack_level is a positive number giving a number of stack frames; the warning will be issued from the currently executing line of code in that stack frame. A stack_level of 1 is the function calling PyErr_WarnEx() , 2 is the function above that, and so forth.

This function normally prints a warning message to sys.stderr ; however, it is also possible that the user has specified that warnings are to be turned into errors, and in that case this will raise an exception. It is also possible that the function raises an exception because of a problem with the warning machinery (the implementation imports the warnings module to do the heavy lifting). The return value is 0 if no exception is raised, or -1 if an exception is raised. (It is not possible to determine whether a warning message is actually printed, nor what the reason is for the exception; this is intentional.) If an exception is raised, the caller should do its normal exception handling (for example, Py_DECREF() owned references and return an error value).

Warning categories must be subclasses of Warning ; the default warning category is RuntimeWarning . The standard Python warning categories are available as global variables whose names are PyExc_ followed by the Python exception name. These have the type PyObject* ; they are all class objects. Their names are PyExc_Warning , PyExc_UserWarning , PyExc_UnicodeWarning , PyExc_DeprecationWarning , PyExc_SyntaxWarning , PyExc_RuntimeWarning ,和 PyExc_FutureWarning . PyExc_Warning 是子类化的 PyExc_Exception ; the other warning categories are subclasses of PyExc_Warning .

For information about warning control, see the documentation for the warnings module and the -W option in the command line documentation. There is no C API for warning control.

int PyErr_WarnExplicitObject ( PyObject  *category , PyObject  *message , PyObject  *filename , int  lineno , PyObject  *module , PyObject  *registry )

Issue a warning message with explicit control over all warning attributes. This is a straightforward wrapper around the Python function warnings.warn_explicit() , see there for more information. The module and registry arguments may be set to NULL to get the default effect described there.

3.4 版新增。

int PyErr_WarnExplicit ( PyObject  *category , const char  *message , const char  *filename , int  lineno , const char  *module , PyObject  *registry )

类似于 PyErr_WarnExplicitObject() 除了 message and module are UTF-8 encoded strings, and filename is decoded from the filesystem encoding ( os.fsdecode() ).

int PyErr_WarnFormat ( PyObject  *category , Py_ssize_t  stack_level , const char  *format , ... )

函数类似于 PyErr_WarnEx() ,但使用 PyUnicode_FromFormat() to format the warning message. format 是 ASCII 编码字符串。

3.2 版新增。

int PyErr_CheckSignals ( )

This function interacts with Python’s signal handling. It checks whether a signal has been sent to the processes and if so, invokes the corresponding signal handler. If the signal module is supported, this can invoke a signal handler written in Python. In all cases, the default effect for SIGINT is to raise the KeyboardInterrupt exception. If an exception is raised the error indicator is set and the function returns -1 ;否则函数返回 0 . The error indicator may or may not be cleared if it was previously set.

void PyErr_SetInterrupt ( )

This function simulates the effect of a SIGINT signal arriving — the next time PyErr_CheckSignals() is called, KeyboardInterrupt will be raised. It may be called without holding the interpreter lock.

int PySignal_SetWakeupFd ( int  fd )

This utility function specifies a file descriptor to which a '\0' byte will be written whenever a signal is received. It returns the previous such file descriptor. The value -1 disables the feature; this is the initial state. This is equivalent to signal.set_wakeup_fd() in Python, but without any error checking. fd should be a valid file descriptor. The function should only be called from the main thread.

PyObject * PyErr_NewException ( const char  *name , PyObject  *base , PyObject  *dict )
返回值:新引用。

此实用函数创建并返回新的异常类。 name 自变量必须是新异常的名称,C 字符串形式 module.classname base and dict 自变量通常为 NULL 。这创建的类对象派生自 Exception (在 C 中可访问按 PyExc_Exception ).

The __module__ attribute of the new class is set to the first part (up to the last dot) of the name argument, and the class name is set to the last part (after the last dot). The base argument can be used to specify alternate base classes; it can either be only one class or a tuple of classes. The dict argument can be used to specify a dictionary of class variables and methods.

PyObject * PyErr_NewExceptionWithDoc ( const char  *name , const char  *doc , PyObject  *base , PyObject  *dict )
返回值:新引用。

如同 PyErr_NewException() , except that the new exception class can easily be given a docstring: If doc 为非 NULL , it will be used as the docstring for the exception class.

3.2 版新增。

void PyErr_WriteUnraisable ( PyObject  *obj )

此实用函数将警告消息打印到 sys.stderr 当异常有设置但解释器实际引发异常不可能时。使用它,例如,当异常发生在 __del__() 方法。

调用函数采用单自变量 obj that identifies the context in which the unraisable exception occurred. The repr of obj 将被打印在警告消息中。

异常对象

PyObject * PyException_GetTraceback ( PyObject  *ex )
返回值:新引用。

Return the traceback associated with the exception as a new reference, as accessible from Python through __traceback__ . If there is no traceback associated, this returns NULL .

int PyException_SetTraceback ( PyObject  *ex , PyObject  *tb )

将回溯关联异常设为 tb 。使用 Py_None 以清零它。

PyObject * PyException_GetContext ( PyObject  *ex )

Return the context (another exception instance during whose handling ex was raised) associated with the exception as a new reference, as accessible from Python through __context__ . If there is no context associated, this returns NULL .

void PyException_SetContext ( PyObject  *ex , PyObject  *ctx )

Set the context associated with the exception to ctx 。使用 NULL to clear it. There is no type check to make sure that ctx is an exception instance. This steals a reference to ctx .

PyObject * PyException_GetCause ( PyObject  *ex )

返回原因 (异常实例,或 None , set by raise ... from ... ) associated with the exception as a new reference, as accessible from Python through __cause__ .

void PyException_SetCause ( PyObject  *ex , PyObject  *cause )

Set the cause associated with the exception to cause 。使用 NULL to clear it. There is no type check to make sure that cause is either an exception instance or None . This steals a reference to cause .

__suppress_context__ 被隐式设为 True 通过此函数。

Unicode 异常对象

The following functions are used to create and modify Unicode exceptions from C.

PyObject * PyUnicodeDecodeError_Create ( const char  *encoding , const char  *object , Py_ssize_t  length , Py_ssize_t  start , Py_ssize_t  end , const char  *reason )

创建 UnicodeDecodeError object with the attributes encoding , object , length , start , end and reason . encoding and reason are UTF-8 encoded strings.

PyObject * PyUnicodeEncodeError_Create ( const char  *encoding , const Py_UNICODE  *object , Py_ssize_t  length , Py_ssize_t  start , Py_ssize_t  end , const char  *reason )

创建 UnicodeEncodeError object with the attributes encoding , object , length , start , end and reason . encoding and reason are UTF-8 encoded strings.

PyObject * PyUnicodeTranslateError_Create ( const Py_UNICODE  *object , Py_ssize_t  length , Py_ssize_t  start , Py_ssize_t  end , const char  *reason )

创建 UnicodeTranslateError object with the attributes object , length , start , end and reason . reason is an UTF-8 encoded string.

PyObject * PyUnicodeDecodeError_GetEncoding ( PyObject  *exc )
PyObject * PyUnicodeEncodeError_GetEncoding ( PyObject  *exc )

返回 encoding 属性为给定异常对象。

PyObject * PyUnicodeDecodeError_GetObject ( PyObject  *exc )
PyObject * PyUnicodeEncodeError_GetObject ( PyObject  *exc )
PyObject * PyUnicodeTranslateError_GetObject ( PyObject  *exc )

返回 object 属性为给定异常对象。

int PyUnicodeDecodeError_GetStart ( PyObject  *exc , Py_ssize_t  *start )
int PyUnicodeEncodeError_GetStart ( PyObject  *exc , Py_ssize_t  *start )
int PyUnicodeTranslateError_GetStart ( PyObject  *exc , Py_ssize_t  *start )

获取 start attribute of the given exception object and place it into *start . start 不得为 NULL 。返回 0 当成功时, -1 当故障时。

int PyUnicodeDecodeError_SetStart ( PyObject  *exc , Py_ssize_t  start )
int PyUnicodeEncodeError_SetStart ( PyObject  *exc , Py_ssize_t  start )
int PyUnicodeTranslateError_SetStart ( PyObject  *exc , Py_ssize_t  start )

设置 start attribute of the given exception object to start 。返回 0 当成功时, -1 当故障时。

int PyUnicodeDecodeError_GetEnd ( PyObject  *exc , Py_ssize_t  *end )
int PyUnicodeEncodeError_GetEnd ( PyObject  *exc , Py_ssize_t  *end )
int PyUnicodeTranslateError_GetEnd ( PyObject  *exc , Py_ssize_t  *end )

获取 end attribute of the given exception object and place it into *end . end 不得为 NULL 。返回 0 当成功时, -1 当故障时。

int PyUnicodeDecodeError_SetEnd ( PyObject  *exc , Py_ssize_t  end )
int PyUnicodeEncodeError_SetEnd ( PyObject  *exc , Py_ssize_t  end )
int PyUnicodeTranslateError_SetEnd ( PyObject  *exc , Py_ssize_t  end )

设置 end attribute of the given exception object to end 。返回 0 当成功时, -1 当故障时。

PyObject * PyUnicodeDecodeError_GetReason ( PyObject  *exc )
PyObject * PyUnicodeEncodeError_GetReason ( PyObject  *exc )
PyObject * PyUnicodeTranslateError_GetReason ( PyObject  *exc )

返回 reason 属性为给定异常对象。

int PyUnicodeDecodeError_SetReason ( PyObject  *exc , const char  *reason )
int PyUnicodeEncodeError_SetReason ( PyObject  *exc , const char  *reason )
int PyUnicodeTranslateError_SetReason ( PyObject  *exc , const char  *reason )

设置 reason attribute of the given exception object to reason 。返回 0 当成功时, -1 当故障时。

递归控制

These two functions provide a way to perform safe recursive calls at the C level, both in the core and in extension modules. They are needed if the recursive code does not necessarily invoke Python code (which tracks its recursion depth automatically).

int Py_EnterRecursiveCall ( const char  *where )

Marks a point where a recursive C-level call is about to be performed.

USE_STACKCHECK is defined, this function checks if the OS stack overflowed using PyOS_CheckStack() . In this is the case, it sets a MemoryError and returns a nonzero value.

The function then checks if the recursion limit is reached. If this is the case, a RuntimeError is set and a nonzero value is returned. Otherwise, zero is returned.

where should be a string such as " in instance check" to be concatenated to the RuntimeError message caused by the recursion depth limit.

void Py_LeaveRecursiveCall ( )

Ends a Py_EnterRecursiveCall() . Must be called once for each successful invocation of Py_EnterRecursiveCall() .

Properly implementing tp_repr for container types requires special recursion handling. In addition to protecting the stack, tp_repr also needs to track objects to prevent cycles. The following two functions facilitate this functionality. Effectively, these are the C equivalent to reprlib.recursive_repr() .

int Py_ReprEnter ( PyObject  *object )

Called at the beginning of the tp_repr implementation to detect cycles.

If the object has already been processed, the function returns a positive integer. In that case the tp_repr implementation should return a string object indicating a cycle. As examples, dict objects return {...} and list objects return [...] .

The function will return a negative integer if the recursion limit is reached. In that case the tp_repr implementation should typically return NULL .

Otherwise, the function returns zero and the tp_repr implementation can continue normally.

void Py_ReprLeave ( PyObject  *object )

Ends a Py_ReprEnter() . Must be called once for each invocation of Py_ReprEnter() 返回 0。

标准异常

All standard Python exceptions are available as global variables whose names are PyExc_ followed by the Python exception name. These have the type PyObject* ; they are all class objects. For completeness, here are all the variables:

C 名称 Python 名称 注意事项
PyExc_BaseException BaseException (1)
PyExc_Exception Exception (1)
PyExc_ArithmeticError ArithmeticError (1)
PyExc_LookupError LookupError (1)
PyExc_AssertionError AssertionError  
PyExc_AttributeError AttributeError  
PyExc_BlockingIOError BlockingIOError  
PyExc_BrokenPipeError BrokenPipeError  
PyExc_ChildProcessError ChildProcessError  
PyExc_ConnectionError ConnectionError  
PyExc_ConnectionAbortedError ConnectionAbortedError  
PyExc_ConnectionRefusedError ConnectionRefusedError  
PyExc_ConnectionResetError ConnectionResetError  
PyExc_FileExistsError FileExistsError  
PyExc_FileNotFoundError FileNotFoundError  
PyExc_EOFError EOFError  
PyExc_FloatingPointError FloatingPointError  
PyExc_ImportError ImportError  
PyExc_IndexError IndexError  
PyExc_InterruptedError InterruptedError  
PyExc_IsADirectoryError IsADirectoryError  
PyExc_KeyError KeyError  
PyExc_KeyboardInterrupt KeyboardInterrupt  
PyExc_MemoryError MemoryError  
PyExc_NameError NameError  
PyExc_NotADirectoryError NotADirectoryError  
PyExc_NotImplementedError NotImplementedError  
PyExc_OSError OSError (1)
PyExc_OverflowError OverflowError  
PyExc_PermissionError PermissionError  
PyExc_ProcessLookupError ProcessLookupError  
PyExc_ReferenceError ReferenceError (2)
PyExc_RuntimeError RuntimeError  
PyExc_SyntaxError SyntaxError  
PyExc_SystemError SystemError  
PyExc_TimeoutError TimeoutError  
PyExc_SystemExit SystemExit  
PyExc_TypeError TypeError  
PyExc_ValueError ValueError  
PyExc_ZeroDivisionError ZeroDivisionError  

3.3 版新增: PyExc_BlockingIOError , PyExc_BrokenPipeError , PyExc_ChildProcessError , PyExc_ConnectionError , PyExc_ConnectionAbortedError , PyExc_ConnectionRefusedError , PyExc_ConnectionResetError , PyExc_FileExistsError , PyExc_FileNotFoundError , PyExc_InterruptedError , PyExc_IsADirectoryError , PyExc_NotADirectoryError , PyExc_PermissionError , PyExc_ProcessLookupError and PyExc_TimeoutError were introduced following PEP 3151 .

这些是兼容性别名化的 PyExc_OSError :

C 名称 注意事项
PyExc_EnvironmentError  
PyExc_IOError  
PyExc_WindowsError (3)

3.3 版改变: 这些别名用于单独异常类型。

注意事项:

  1. This is a base class for other standard exceptions.
  2. 这如同 weakref.ReferenceError .
  3. Only defined on Windows; protect code that uses this by testing that the preprocessor macro MS_WINDOWS 有定义。

内容表

上一话题

引用计数

下一话题

实用工具

本页