This is not the solution. The problem is the directory. Either the script lacks the permissions to create a file in that directory, or the directory simply doesn't exist. Show 4 more comments. Community Bot 1 1 1 silver badge. Qwerty Qwerty Loretta Have you checked the value of filename? Yes, I did. It is a unicode string. I am not using a path. You need to properly define encoding for this to work. Show 2 more comments. It is bad to test a file before opening it, as it can lead to race conditions file is deleted before it is opened.
Race conditions can sometimes be used to exploit vulnerabilities in a system. If file doesn't exist, append mode creates it. Does not create file.
Khorkrak Khorkrak 3, 1 1 gold badge 23 23 silver badges 34 34 bronze badges. This is Unpythonic. Rather than checking if the file exists first , one should assume it does first, then handle the case that it doesn't. Granitosaurus Granitosaurus DavidParks good point, just tested it and it is indeed true on ext4 file system and python3.
I don't think that's intended or desired behaviour, maybe it's a bug wtih python? Same thing when using touch at the command line in linux, so I assume it's intended behavior. SilentGhost SilentGhost k 61 61 gold badges silver badges bronze badges. What do you want to do with file? Only writing to it or both read and write? Testing for existence before opening might introduce a race condition.
Probably not a big deal in this case, but something to keep in mind. Angel Poppy Angel Poppy 85 1 1 silver badge 1 1 bronze badge. Next Reading and Writing to text files in Python. Recommended Articles. Article Contributed By :. Easy Normal Medium Hard Expert. Writing code in comment? Please use ide. Load Comments.
What's New. Most popular in Python. More related articles in Python. We use cookies to ensure you have the best browsing experience on our website. Start Your Coding Journey Now! Login Register. If the file isn't in the same directory, you must mention the file's full path when writing the file name parameter.
For instance, to open an "example. Python has several access modes, and these modes govern the operations that you can perform on an open file. In other words, every access mode refers to how the file can be used when it's open differently. Access modes in Python also specify the position of the file handle. You can think of the file handle as a cursor indicating from where the data must be read or written.
That said, using the access mode parameter is optional, as seen in the previous examples. There are two other parameters you can use to specify the mode you want to open the file in. Python reads files in text mode by default, which is specified with the parameter "t.
In contrast, using the binary mode "b" when using the open function returns bytes. Binary mode is typically used when handling non-text files such as images and executables. Here are few examples of using these access modes in Python:. Besides having a cleaner syntax, the "with" statement also makes exception handling easier when working with file objects. It is considered best practice to use the with statement when working with files whenever applicable.
A significant advantage that using the with statement offers is that it automatically closes any files you've opened after the operation is complete.
Thus, you don't have to worry about closing the file and cleaning up after performing any operation on a file. To read a file using the with statement, you would write the following lines of code:.
When the second line of code runs, all of the data stored in "example. If you wanted to write data to the same file, you would run the following code:.
Reading a file in Python is straightforward — you must use the 'r' parameter or not mention a parameter at all since it is the default access mode. That said, there are other ways to read data from a file in Python.
For example, you could use the read size method built into Python to read the specified size of data. If you do not specify the size parameter, the method will read the file until its end. Let's assume that "example. This file has two lines. To read the file using the read method, you would use the following code:. In the example above, the read method returns the new line character when the line ends.
Furthermore, once the end of the file is reached, it returns an empty string. It is possible to change the cursor position regardless of what access mode you're using with the help of the seek method.
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