Python Fileopen Error
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you have probably seen some. There are (at least) two distinguishable kinds of errors: syntax errors and exceptions. 8.1. Syntax Errors¶ Syntax errors, also known as parsing errors, are perhaps the most
Python Exception Message
common kind of complaint you get while you are still learning Python: >>> while python raise custom exception True print('Hello world') File "
Python Print Exception
example, the error is detected at the function print(), since a colon (':') is missing before it. File name and line number are printed so you know where to look in case the input came from a script. 8.2. Exceptions¶ Even if a statement or expression is syntactically correct, it may cause an error when an attempt is made to execute it. Errors detected during execution are called exceptions
Python Try Except Else
and are not unconditionally fatal: you will soon learn how to handle them in Python programs. Most exceptions are not handled by programs, however, and result in error messages as shown here: >>> 10 * (1/0) Traceback (most recent call last): File "
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Name Of Errors In Python
Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of an exception can be in python 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Python's “open()” throws different errors for “file not found” - how to handle both exceptions? up vote 29 https://docs.python.org/3/tutorial/errors.html down vote favorite 6 I have a script where a user is prompted to type a filename (of a file that is to be opened), and if the file doesn't exist in the current directory, the user is prompted again. Here is the short version: file = input("Type filename: ") ... try: fileContent = open(filename, "r") ... except FileNotFoundError: ... When I tested my script on my MacOS X in Python 3.3x http://stackoverflow.com/questions/15032108/pythons-open-throws-different-errors-for-file-not-found-how-to-handle-b it worked perfectly fine when I type the wrong filename on purpose (it executes the suite under "expect"). However, when I wanted to run my code on a Windows computer in Python 3.2x, I get an error that says that "FileNotFoundError" is not defined. So, Python 3.2 on Windows thinks "FileNotFoundError" is a variable and the programs quits with an error. I figured out that Python 3.2 on Windows throws an "IOError" if the input filename is not valid. I tested it on my Linux machine in Python 2.7, and it's also an IOError. My problem is now, that the code with except "FileNotFoundError": won't run on Windows's Python 3.2, but if I change it to except "IOError": it won't work on my Mac anymore. How could I work around it? The only way I can think of is to use just except, which I usually don't want. python python-3.x filenotfoundexception ioerror share|improve this question edited Feb 22 '13 at 19:57 asked Feb 22 '13 at 19:48 user2015601 6 This isn't due to Mac/Windows, it's the version of Python. I would investigate 3.2/3.3 on OS X as well (and 3.3 on Windows), consult the change logs, and then revise the question/title as appropriate. –user166390 Feb 22 '13 at 19:53 add a comment|
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the http://stackoverflow.com/questions/374768/how-do-you-test-a-file-read-error-in-python company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up How do you test a file.read() error in Python? up vote 4 down vote favorite 1 I have the following in python code (adapted from an example given in Dive Into Python) that reads the entire contents of a file into a buffer. buffer = "" try: file = open(postFileName, 'rU') try: # Read the entire POST log file into a buffer buffer += file.read() finally: file.close() except IOError: buffer += "The POST file could not be opened." What's bothering me about this code is the inner try/finally block without an except block. Do I need python fileopen error an except block in there? Can the call to read() fail after the call to open() was successful? I know the try-except-finally is now unified, so adding one, at least syntactically, is not a problem. If I add an except block, under what conditions will it be executed, and how do I write a test to make sure it runs under those conditions? Additionally, if I don't need an except block, then why do I need the inner try/finally block at all? python file-io error-handling share|improve this question edited Aug 3 '12 at 14:06 asked Dec 17 '08 at 14:51 Bill the Lizard 223k139449737 add a comment| 4 Answers 4 active oldest votes up vote 6 down vote accepted I find that finally blocks are often overused. The file close (and a few other similar patterns) are so important that Python 3.0 will have a with statement just to cover this base in a slightly less obscure way. Do I need an except with a finally? That hits on the confusing nature of this specific example, and why they added the with statement. The finally does "no matter what" cleanup. Exception or no exception, the finally is always executed. Can the call to read() fail after the call to open() was successful? All OS calls, all I/O cal