NET Core 1. NET Framework 4. NET Core and. NET Framework starting with version 4. The first segment of the DOS device path after the device path specifier identifies the volume or drive. For example:. This is significant when calling a method such as Path. GetFullPath String, String with relative directory segments; it is never possible to navigate past the volume. DOS device paths are fully qualified by definition. Relative directory segments.
Current directories never enter into their usage. The following example illustrates some of the ways in which you can refer to a file when using the APIs in the System.
IO namespace. The example instantiates a FileInfo object and uses its Name and Length properties to display the filename and the length of the file. Almost all paths passed to Windows APIs are normalized. During normalization, Windows performs the following steps:. This normalization happens implicitly, but you can do it explicitly by calling the Path. The first step in path normalization is identifying the type of path.
Paths fall into one of a few categories:. The type of the path determines whether or not a current directory is applied in some way. It also determines what the "root" of the path is. A path that begins with a legacy device name is always interpreted as a legacy device by the Path.
GetFullPath String method. If a path isn't fully qualified, Windows applies the current directory to it. UNCs and device paths do not have the current directory applied. If the path starts with a single component separator, the drive from the current directory is applied.
If the path starts with a drive letter, volume separator, and no component separator, the last current directory set from the command shell for the specified drive is applied. If the last current directory was not set, the drive alone is applied.
These "drive relative" paths are a common source of program and script logic errors. Assuming that a path beginning with a letter and a colon isn't relative is obviously not correct. If the path starts with something other than a separator, the current drive and current directory are applied.
Relative paths are dangerous in multithreaded applications that is, most applications because the current directory is a per-process setting. Any thread can change the current directory at any time. Starting with. NET Core 2. GetFullPath String, String method to get an absolute path from a relative path and the base path the current directory that you want to resolve it against. The absolute path of a file remains the same everywhere, but the relative path changes depending upon the current working directory.
This phenomenon is demonstrated in the following coding example. File Path in Python A file path specifies the location of a file in the computer. Current Working Directory The current working directory or cwd in short is the directory from which the program is being executed.
We can get the absolute path of the current file as shown below. DelftStack is a collective effort contributed by software geeks like you. If you like the article and would like to contribute to DelftStack by writing paid articles, you can check the write for us page. This answer is now outdated, as the top answer has been edited to use a proper relative path in os.
What is left is the preference to use separate strings for each path element over hardcoding the path separator. MartijnPieters Yes, the top answer has been edited to match this in part, but the separate strings is not a preference - separating the stings like this makes it os-independent.
Further resolve calls are only needed if you need to resolve symlinks. Fahad Haleem Fahad Haleem 6 6 silver badges 5 5 bronze badges. Tom Leys Tom Leys That's not necessarily true. Usually sys. If you want the current directory, use os. The original poster commented that the current working directory is the wrong place to base the relative path from. You are correct in saying that sys.
No, sys. Python code can be invoked with -c or -m or via an embedded interpreter, at which point sys. It retrieves info for all stack frames, which you then discard and only get the top one for. It basically calls inspect. Chandrajyoti Das Chandrajyoti Das 55 5 5 bronze badges. This code will return the absolute path to the main script. BookOwl BookOwl 3 3 silver badges 11 11 bronze badges. Instead of re-importing, you'd use sys. J0hnG4lt J0hnG4lt 3, 4 4 gold badges 21 21 silver badges 38 38 bronze badges.
Markus Dutschke Markus Dutschke 6, 2 2 gold badges 43 43 silver badges 44 44 bronze badges. Example Here's an example, tested in Python '3. Whitecat Whitecat 3, 5 5 gold badges 45 45 silver badges 73 73 bronze badges. This relies on the current working directory, which could be radically different from what you actually want. A simple solution would be import os os. Qin Heyang Qin Heyang 9 9 silver badges 12 12 bronze badges. Shivam Bharadwaj Shivam Bharadwaj 1, 19 19 silver badges 18 18 bronze badges.
Samie Bencherif Samie Bencherif 1, 10 10 silver badges 24 24 bronze badges. The want to work from the scripts location. Sign up or log in Sign up using Google.
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