Re: pathlib.Path.is_file vs os.path.isfile difference
> On 10 Mar 2024, at 14:49, Thomas Passin via Python-list > wrote: > > That and there's a registry setting: > > https://learn.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation > Yep that and rules about size of parts of the path. Barry -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 3/10/2024 9:33 AM, Albert-Jan Roskam wrote: On Mar 10, 2024 12:59, Thomas Passin via Python-list wrote: On 3/10/2024 6:17 AM, Barry wrote: > > >> On 8 Mar 2024, at 23:19, Thomas Passin via Python-list wrote: >> >> We just learned a few posts back that it might be specific to Linux; I ran it on Windows. > > Depending on the exact win32 api used there is a 257 limit on windows. > The 257 includes 2 for the device, C:, and 255 for the path part that will use 1 for the leading \. Getting an error for a name that is 255 is not surprising. > > Other api allow for 65535 limit, not sure on its additional limits. I seem to remember there is a setting to allow longer paths, but I forget any details. = You mean the "\\?\" prefix? https://learn.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation?tabs=registry That and there's a registry setting: https://learn.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On Mar 10, 2024 12:59, Thomas Passin via Python-list wrote: On 3/10/2024 6:17 AM, Barry wrote: > > >> On 8 Mar 2024, at 23:19, Thomas Passin via Python-list wrote: >> >> We just learned a few posts back that it might be specific to Linux; I ran it on Windows. > > Depending on the exact win32 api used there is a 257 limit on windows. > The 257 includes 2 for the device, C:, and 255 for the path part that will use 1 for the leading \. Getting an error for a name that is 255 is not surprising. > > Other api allow for 65535 limit, not sure on its additional limits. I seem to remember there is a setting to allow longer paths, but I forget any details. = You mean the "\\?\" prefix? https://learn.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation?tabs=registry -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 3/10/2024 6:17 AM, Barry wrote: On 8 Mar 2024, at 23:19, Thomas Passin via Python-list wrote: We just learned a few posts back that it might be specific to Linux; I ran it on Windows. Depending on the exact win32 api used there is a 257 limit on windows. The 257 includes 2 for the device, C:, and 255 for the path part that will use 1 for the leading \. Getting an error for a name that is 255 is not surprising. Other api allow for 65535 limit, not sure on its additional limits. I seem to remember there is a setting to allow longer paths, but I forget any details. -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
> On 8 Mar 2024, at 23:19, Thomas Passin via Python-list > wrote: > > We just learned a few posts back that it might be specific to Linux; I ran it > on Windows. Depending on the exact win32 api used there is a 257 limit on windows. The 257 includes 2 for the device, C:, and 255 for the path part that will use 1 for the leading \. Getting an error for a name that is 255 is not surprising. Other api allow for 65535 limit, not sure on its additional limits. Barry -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 2024-03-08, Thomas Passin via Python-list wrote: > >> Hi, I tested this with Python 3.8. Good to know that this was fixed! > > We just learned a few posts back that it might be specific to Linux; I > ran it on Windows. On Linux, the limit is imposed by the filesystem. Most of the "real" filesystems on Linux have a 255 character limit, a few support 256, and some of the legacy filesystems have lower limits. Reiser4 is the only one that's even remotely common which supports more than 256 -- according to https://en.wikipedia.org/wiki/Comparison_of_file_systems#Limits it supports filenames up to 3976 bytes long. NB: The behavior when the limit is exceeded might also vary from one filesystem to another. In any case, the pathlib docs for is_file() are explicit: any errors from the underlying OS and libraries will be propogated. There is nothing to fix. https://docs.python.org/3/library/pathlib.html#pathlib.Path.is_file Path.is_file() Return True if the path points to a regular file (or a symbolic link pointing to a regular file), False if it points to another kind of file. False is also returned if the path doesn’t exist or is a broken symlink; other errors (such as permission errors) are propagated. -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 3/8/2024 5:14 PM, Albert-Jan Roskam wrote: On Mar 8, 2024 19:35, Thomas Passin via Python-list wrote: On 3/8/2024 1:03 PM, Albert-Jan Roskam via Python-list wrote: > Hi, > I was replacing some os.path stuff with Pathlib and I discovered this: > Path(256 * "x").is_file() # OSError > os.path.isfile(256 * "x") # bool > Is this intended? Does pathlib try to resemble os.path as closely as > possible? You must have an very old version of Python. I'm running 3.12.2 and it returns False. Either that or that path name exists and throws some kind of unexpected exception. Hi, I tested this with Python 3.8. Good to know that this was fixed! We just learned a few posts back that it might be specific to Linux; I ran it on Windows. -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On Mar 8, 2024 19:35, Thomas Passin via Python-list wrote: On 3/8/2024 1:03 PM, Albert-Jan Roskam via Python-list wrote: > Hi, > I was replacing some os.path stuff with Pathlib and I discovered this: > Path(256 * "x").is_file() # OSError > os.path.isfile(256 * "x") # bool > Is this intended? Does pathlib try to resemble os.path as closely as > possible? You must have an very old version of Python. I'm running 3.12.2 and it returns False. Either that or that path name exists and throws some kind of unexpected exception. Hi, I tested this with Python 3.8. Good to know that this was fixed! -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 3/8/2024 2:21 PM, Grant Edwards via Python-list wrote: On 2024-03-08, Thomas Passin via Python-list wrote: On 3/8/2024 1:03 PM, Albert-Jan Roskam via Python-list wrote: Hi, I was replacing some os.path stuff with Pathlib and I discovered this: Path(256 * "x").is_file() # OSError os.path.isfile(256 * "x") # bool Is this intended? Does pathlib try to resemble os.path as closely as possible? You must have an very old version of Python. I'm running 3.12.2 and it returns False. It throws OSError with Python 3.11.8 on Linux. Sorry, I should have said on Windows. $ python Python 3.11.8 (main, Feb 23 2024, 16:11:29) [GCC 13.2.1 20240113] on linux Type "help", "copyright", "credits" or "license" for more information. import pathlib pathlib.Path(256 * "x").is_file() Traceback (most recent call last): File "", line 1, in File "/usr/lib/python3.11/pathlib.py", line 1267, in is_file return S_ISREG(self.stat().st_mode) ^^^ File "/usr/lib/python3.11/pathlib.py", line 1013, in stat return os.stat(self, follow_symlinks=follow_symlinks) ^^ OSError: [Errno 36] File name too long: '' import os os.path.isfile(256 * "x") False -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 2024-03-08, Grant Edwards via Python-list wrote: >> OSError: [Errno 36] File name too long: >> '' > > On all of the Linux filesystems I know about, the max length for a > filename is 255 bytes, so the OSError is too surprising, and it does > seem to follow the documentation. Doh. I meant "is not too surprising". -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 2024-03-08, Grant Edwards via Python-list wrote: > On 2024-03-08, Thomas Passin via Python-list wrote: >> On 3/8/2024 1:03 PM, Albert-Jan Roskam via Python-list wrote: >>> Hi, >>> I was replacing some os.path stuff with Pathlib and I discovered this: >>> Path(256 * "x").is_file() # OSError >>> os.path.isfile(256 * "x") # bool >>> Is this intended? Does pathlib try to resemble os.path as closely as >>> possible? >> >> You must have an very old version of Python. I'm running 3.12.2 and it >> returns False. > > It throws OSError with Python 3.11.8 on Linux. > OSError: [Errno 36] File name too long: > '' On all of the Linux filesystems I know about, the max length for a filename is 255 bytes, so the OSError is too surprising, and it does seem to follow the documentation. import os os.path.isfile(256 * "x") > False However, os.path.isfile() apprently masks that error somehow and returns False instead. I notice that the os.path.isfile() documentation does not specify what happens if the path is not a file or is illegal. It only specifies that True is returned if the path is a regular file. Presumably something other than "return True" is supposed to happen, but exactly what is not specified. -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 2024-03-08, Thomas Passin via Python-list wrote: > On 3/8/2024 1:03 PM, Albert-Jan Roskam via Python-list wrote: >> Hi, >> I was replacing some os.path stuff with Pathlib and I discovered this: >> Path(256 * "x").is_file() # OSError >> os.path.isfile(256 * "x") # bool >> Is this intended? Does pathlib try to resemble os.path as closely as >> possible? > > You must have an very old version of Python. I'm running 3.12.2 and it > returns False. It throws OSError with Python 3.11.8 on Linux. $ python Python 3.11.8 (main, Feb 23 2024, 16:11:29) [GCC 13.2.1 20240113] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import pathlib >>> pathlib.Path(256 * "x").is_file() Traceback (most recent call last): File "", line 1, in File "/usr/lib/python3.11/pathlib.py", line 1267, in is_file return S_ISREG(self.stat().st_mode) ^^^ File "/usr/lib/python3.11/pathlib.py", line 1013, in stat return os.stat(self, follow_symlinks=follow_symlinks) ^^ OSError: [Errno 36] File name too long: '' >>> >>> import os >>> os.path.isfile(256 * "x") False -- https://mail.python.org/mailman/listinfo/python-list
Re: pathlib.Path.is_file vs os.path.isfile difference
On 3/8/2024 1:03 PM, Albert-Jan Roskam via Python-list wrote: Hi, I was replacing some os.path stuff with Pathlib and I discovered this: Path(256 * "x").is_file() # OSError os.path.isfile(256 * "x") # bool Is this intended? Does pathlib try to resemble os.path as closely as possible? You must have an very old version of Python. I'm running 3.12.2 and it returns False. Either that or that path name exists and throws some kind of unexpected exception. The Python docs say "Return True if the path points to a regular file (or a symbolic link pointing to a regular file), False if it points to another kind of file. False is also returned if the path doesn’t exist or is a broken symlink; other errors (such as permission errors) are propagated" -- https://mail.python.org/mailman/listinfo/python-list
