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   Ayo (ayo@lonely.town)'s status on Thursday, 08-Aug-2024 21:29:10 JST Ayo

   Early draft documenting ncdu's new binary export format:
   https://dev.yorhel.nl/ncdu/binfmt

   Feedback welcome, both on the format and the document.

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     Haelwenn /элвэн/ :triskell: (lanodan@queer.hacktivis.me)'s status on Thursday, 08-Aug-2024 21:29:08 JST Haelwenn /элвэн/ :triskell:

     in reply to
     @ayo Looking at the way CBOR encodes strings… might make sense to use a more usual length-prefix encoding for it?
     And AFAIK the maximum length for filenames in all filesystems is 255 (cf. NAME_MAX) so could be just u8 for the length.
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     Ayo (ayo@lonely.town)'s status on Thursday, 08-Aug-2024 22:26:55 JST Ayo

     in reply to

     • Haelwenn /элвэн/ :triskell:

     @lanodan Oh yeah, I forgot to document that ncdu doesn't support indefinite-length strings for the name field, they must be length-prefixed (That is such a CBOR misfeature).

     The maximum length is actually a bit larger than that; the root item contains the full path of the scanned directory instead of just the name, and some filesystems apparently allow for 255 codepoints instead of bytes: https://en.wikipedia.org/wiki/Comparison_of_file_systems#Limits

     Haelwenn /элвэн/ :triskell: likes this.
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     Haelwenn /элвэн/ :triskell: (lanodan@queer.hacktivis.me)'s status on Thursday, 08-Aug-2024 22:29:51 JST Haelwenn /элвэн/ :triskell:

     in reply to
     @ayo Oh interesting, makes me wonder how Linux deals with such filesystems, would be quite ironic if exFAT on Linux for example ends up like DOS with truncated name, ~, and a number.
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     Ayo (ayo@lonely.town)'s status on Thursday, 08-Aug-2024 22:34:59 JST Ayo

     in reply to

     • Haelwenn /элвэн/ :triskell:

     @lanodan That sure would be funny, but I expect the Linux VFS layer to support longer names; most(?) syscall arguments are limited to PATH_MAX rather than NAME_MAX. Need to give it a try, though. :blobcatthinking:

     Haelwenn /элвэн/ :triskell: likes this.