This is not strictly true as the NTFS filesystem supports paths up to 32k characters. A detailed explanation of long path from the. Net BCL team blog. A small excerpt highlights the issue with long paths. Another concern is inconsistent behavior that would result by exposing long path support.
So this means MoveFile will let you move a DLL to a location such that its path is longer than characters, but when you try to load the DLL, it would fail.
There are similar examples throughout the Windows APIs; some workarounds exist, but they are on a case-by-case basis. The question is why does the limitation still exist.
Why has the limitation not been removed? Through API contract, Windows has guaranteed all applications that the standard file APIs will never return a path longer than characters. My application used that defined value. My structure is correctly defined, and only allocates bytes total. That means that i am only able to receive a filename that is less than characters. Windows promised me that if i wrote my application correctly, my application would continue to work in the future.
If Windows were to allow filenames longer than characters then my existing application which used the correct API correctly would fail. For example, i still own and use a Windows application that was written to run on Windows 3. It still runs on bit Windows That is what backwards compatibility gets you. Microsoft did create a way to use the full 32, path names; but they had to create a new API contract to do it. For one, you should use the Shell API to enumerate files as not all files exist on a hard drive or network share.
But they also have to not break existing user applications. The vast majority of applications do not use the shell api for file work. From Windows However, you must opt-in to the new behavior. A registry key allows you to enable or disable the new long path behavior. The key's value will be cached by the system per process after the first call to an affected Win32 file or directory function list follows. The registry key will not be reloaded during the lifetime of the process.
In order for all apps on the system to recognize the value of the key, a reboot might be required because some processes may have started before the key was set. You can also enable the new long path behavior per app via the manifest:.
You can mount a folder as a drive. As to why this still exists - MS doesn't consider it a priority, and values backwards compatibility over advancing their OS at least in this instance. A workaround I use is to use the "short names" for the directories in the path, instead of their standard, human-readable versions. As to how to cope with the path size limitation on Windows - using 7zip to pack and unpack your path-length sensitive files seems like a viable workaround.
I've used it to transport several IDE installations those Eclipse plugin paths, yikes! Not really sure how it evades the char limit set by Windows from a technical PoV , but hey, it works! More details on their SourceForge page here :. But it's disabled in SFX code. Some users don't like long paths, since they don't understand how to work with them. That is why I have disabled it in SFX code.
Otherwise the "Temp" folder will be used as an interim cache and you'll bounce into the same char limitation once Windows Explorer starts moving the files to their "final resting place". See the replies to this question for more information. It does, and it is a default for some reason, but you could easily override it with this registry key:.
Another way to cope with it is to use Cygwin, depending on what do you want to do with the files i. For example it allows to copy, move or rename files that even Windows Explorer can't. Or of course deal with the contents of them like md5sum, grep, gzip, etc.
Also for programs that you are coding, you could link them to the Cygwin DLL and it would enable them to use long paths I haven't tested this though. How are we doing? Please help us improve Stack Overflow. Take our short survey. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Why does the character path length limit exist in Windows?
Ask Question. Asked 12 years, 1 month ago. Active 1 month ago. Viewed k times. I have come up against this problem a few times at inopportune moments: Trying to work on open source Java projects with deep paths Storing deep Fitnesse wiki trees in source control An error trying to use Bazaar to import my source control tree Why does this limit exist? Why hasn't it been removed yet? Ajay Jeffrey Cameron Jeffrey Cameron 9, 10 10 gold badges 42 42 silver badges 76 76 bronze badges.
So, we have our chars for the whole path, including the file name, the extension, and the NUL terminator. Hi Gundage Vishal ,. Please refer to the link below about why does the character path length limit exist in Windows to get more information. Please Note: Since the website is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information. Hope it will be helpful to you. Please remember to mark the replies as answers if they help.
If you have feedback for TechNet Subscriber Support, contact tnmff microsoft. I am proposing previous helpful replies as "Answered".
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Best regards, Carl. Seriously, generally speaking it is characters, but that comes with caveats. In real-world, common usage, the max is Here is why:. The maximum Windows filename length to the operating system is characters, however that includes a number of required characters that lower the effective number. So, that takes the down to characters as an absolute maximum. That would be the case only if you had a very long filename with no extension and it was located on the root folder of the disk.
Looking at more common and realistic scenarios, your effective maximum is going to be significantly lower. Add an extension very common , and your maximum length drops to or characters, depending on the length of the extension most are 3 characters; some are 4 - e. Each directory name in the path of the filename must be included in that characters.
This is why errors sometimes occur when moving files between directories. Users are often confused by the "filename too long" message when they see a short filename. The reason for the error is the total path length must conform to the filename maximum length.
Windows makes no distinction in filename storage between the path and filenames. They are stored in the same space.
To request 8. This is true even if a long file name contains extended characters, regardless of the code page that is active during a disk read or write operation.
Files using long file names can be copied between NTFS file system partitions and Windows FAT file system partitions without losing any file name information. In this case, the short file name is substituted if possible. The path to a specified file consists of one or more components , separated by a special character a backslash , with each component usually being a directory name or file name, but with some notable exceptions discussed below.
It is often critical to the system's interpretation of a path what the beginning, or prefix , of the path looks like. This prefix determines the namespace the path is using, and additionally what special characters are used in which position within the path, including the last character. Each component of a path will also be constrained by the maximum length specified for a particular file system. In general, these rules fall into two categories: short and long.
Note that directory names are stored by the file system as a special type of file, but naming rules for files also apply to directory names. To summarize, a path is simply the string representation of the hierarchy between all of the directories that exist for a particular file or directory name. For Windows API functions that manipulate files, file names can often be relative to the current directory, while some APIs require a fully qualified path.
A file name is relative to the current directory if it does not begin with one of the following:. If a file name begins with only a disk designator but not the backslash after the colon, it is interpreted as a relative path to the current directory on the drive with the specified letter.
Note that the current directory may or may not be the root directory depending on what it was set to during the most recent "change directory" operation on that disk.
Examples of this format are as follows:. A path is also said to be relative if it contains "double-dots"; that is, two periods together in one component of the path.
This special specifier is used to denote the directory above the current directory, otherwise known as the "parent directory". Relative paths can combine both example types, for example "C This is useful because, although the system keeps track of the current drive along with the current directory of that drive, it also keeps track of the current directories in each of the different drive letters if your system has more than one , regardless of which drive designator is set as the current drive.
In later versions of Windows, changing a registry key or using the Group Policy tool is required to remove the limit. See Maximum Path Length Limitation for full details. There are two main categories of namespace conventions used in the Windows APIs, commonly referred to as NT namespaces and the Win32 namespaces.
The NT namespace was designed to be the lowest level namespace on which other subsystems and namespaces could exist, including the Win32 subsystem and, by extension, the Win32 namespaces. Early versions of Windows also defined several predefined, or reserved, names for certain special devices such as communications serial and parallel ports and the default display console as part of what is now called the NT device namespace, and are still supported in current versions of Windows for backward compatibility.
The Win32 namespace prefixing and conventions are summarized in this section and the following section, with descriptions of how they are used. Note that these examples are intended for use with the Windows API functions and do not all necessarily work with Windows shell applications such as Windows Explorer.
For this reason there is a wider range of possible paths than is usually available from Windows shell applications, and Windows applications that take advantage of this can be developed using these namespace conventions.
For more information about the normal maximum path limitation, see the previous section Maximum Path Length Limitation. This is how access to physical disks and volumes is accomplished directly, without going through the file system, if the API supports this type of access. You can access many devices other than disks this way using the CreateFile and DefineDosDevice functions, for example.
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