![]() Once this count reaches 0 the memory segment on which the file is located is marked as free, meaning that the system will eventually overwrite it with another data (effectively deleting the previous file - which doesn't happen for at least as long as a running process has an opened stream associated with the file, but that's another story). For every file the system keeps a count of its hard links. I'd like to add that hard links allow for an easy method of file backup. These penalties do not exist with hard links because they are built into the very structure of the filesystem. ![]() The link also takes a small amount of space on the disk, to hold the text of the link. Soft links are an extra layer of indirection on top of normal file access the kernel has to dereference the link when you open the file, and this takes a small amount of time. The main advantage of hard links is that, compared to soft links, there is no size or speed penalty. This question has already been answered here, quoting from the accepted answer: If it is unavailable, using it will raise a NotImplementedError. You can check whether or not follow_symlinks is supported on your platform using os.supports_follow_symlinks. (For POSIX systems, Python will call the l. Not following symlinks: If follow_symlinks is False, and the last element of the path to operate on is a symbolic link, the function will operate on the symbolic link itself instead of the file the link points to. This name resolution also happens when calling functions in os with an (optional) parameter follow_symlinks set to True, however, if it's set to False the name does not get resolved (for instance you'd set it to false when you want to manipulate the symlink itself not the object it points to). More specific to your question, if I pass /home/gst/Desktop/mycat.png to os.readlink it will return /home/gst/mydog.png. When I create a symbolic link I create a file that contains a path to another file (which might be another symbolic link). If I create a hard link (for example by calling os.link) I just add entries to the relevant directory files, such that the specific name can be followed to the linked object. By following the symlink located at /home/gst/Desktop/mycat.png I actually (try to) access an object pointed to by /home/gst/mydog.png. When I try to open it, the name /home/gst/Desktop/mycat.png is usually resolved to /home/gst/mydog.png. For example, say that I created a symbolic link to /home/gst/mydog.png at /home/gst/Desktop/mycat.png with os.symlink("/home/gst/mydog.png", "/home/gst/Desktop/mycat.png"). Rather it just saves a path to an object. A symlink on the other hand does not point directly to an object. Hard vs Symbolic linksĪ hard link is just a mapping like the one we discussed previously. Which brings us to hard and symbolic links. Going back to directory files, the mappings they contain are called links. ![]() Basically, if I give you a name like /home/gst/mydog.png the accessing process will first look into the / directory (the root directory) where it will find information on where to find home, then opening that file it will look into it to see where gst is and finally in that file it will try to find the location of mydog.png, and if successful try do whatever it set out to do with it. Directories are files that contain mappings from names (paths) to inodes, which are just unique identifiers of different objects residing on your system. Links and files on LinuxĪs a rule of thumb, in Linux everything is treated as a file. This will be a bit of a roundabout, but I find it that symbolic links or symlinks are best explained together with hard links and generic properties of a filesystem on Linux. If you're interested in how this relates to Windows I suggest you look for tutorials like this one. I will answer this from a perspective of an *nix user (specifically Linux). ![]()
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