Filename Character Length Limit...

[JoelBC]

Is there a limit to the number of characters in a filename and, if yes:

1. What is the limit in HFS format [i.e. Macintosh HD:Userocuments:...]?

2. What is the limit in POSIX format [i.e. ~/Users/Documents/...]?

3. Which is better / preferred in terms of the ability to transfer file between devices so that files are not missed [i.e. not copied / not moved] because their filename length is too long?

Thanks in advance,

Joel

 

[maflynn]

Searching the google, I easily came up with 255 characters for bot HFS+ POSIX file formats.

I'd say the best one is native file format for OS X, that is HFS+ is better for OSX.

 

[NoBoMac]

Don't forget to add into the equation the length of a pathname, which is 1024 in OS X (and generally most *nix boxes).

Sure, can have folders and files with 255 chars, but that limits number of sub-folders possible.

"Strict" POSIX is 14 characters for files, 256 for paths, but doubt one will see something setup like that in this day and age.

$ getconf _POSIX_NAME_MAX
14
$ getconf _POSIX_PATH_MAX
256
$ getconf _XOPEN_NAME_MAX
255
$ getconf _XOPEN_PATH_MAX
1024

 

[Partron22]

Searching the google , I easily...

I got the same answer easily by renaming a file in Finder; just keep typing until it beeps at you, then paste the result into BBEdit to get a character count.
Any extension e.g. .jpg, counts toward the limit.

HFS limit used to be 31 characters.
HFS+ limit is 255-character unicode file names

 

[JoelBC]

Appreciate all the responses...so, to summarize to make sure I have this right:

1. HFS+ Format...the limit is 255 characters which starts with "Macintosh HD" and ends with the filename extension [i.e. .doc]. Is this correct.

2. POSIX Format...the limit is 255 characters which starts with "User" [i.e. as is User/UserName/Documents/test_file.doc] and ends with the file extension.


If this is not correct then please correct.

One last thing, why it is better to count / work in than in POSIX?

Thanks.

 

[NoBoMac]

Re: lengths. No, you have it wrong. Maybe I'm miss reading the post.

255 for individual file/folder name, with the path being a total of 1024 characters, with all the "/" and path prefix to a given file.

So, can build a path/structure:

/Users/myusername/<255charfoldername>/<255filenamewith.ext>

This would be a 529 character pathname with two 255 "files" (folders are really files in *nix world).

 

[JoelBC]

Re: lengths. No, you have it wrong. Maybe I'm miss reading the post.

255 for individual file/folder name, with the path being a total of 1024 characters, with all the "/" and path prefix to a given file.

So, can build a path/structure:

/Users/myusername/<255charfoldername>/<255filenamewith.ext>

This would be a 529 character pathname with two 255 "files" (folders are really files in *nix world).

Appreciate the clarification which I know understand subject to the following:

1. Please confirm that the pathname DOES INCLUDE the "/" in "/Users'.

2. Please confirm that the "/" before either the folder name or filename count as part of the pathname but do not count as part of the filename.

Thx..