Finder refuses to copy files with sizes over 4 GB (not GiB!) to FAT32 volumes

Originator:SaagarJha28
Number:rdar://33143902 Date Originated:05-Jul-2017 02:55 PM
Status:Open Resolved:
Product:macOS + SDK (Finder) Product Version:macOS High Sierra 10.13 Beta (17A291m)
Classification:Serious Bug Reproducible:
 
Area:
Finder

Summary:
Finder will refuse to copy any file over 4 GB (4,000,000,000 bytes) to a FAT32 volume, claiming that it is too large for the volume's format (see screenshot). However, the limit for FAT32 is actually 4 GiB (4,294,967,296 bytes)–as evidenced by cp, which will happily comply.

Steps to Reproduce:
1. Acquire a FAT32 volume with more than 4 GiB free space.
2. Create a 4.001 GB (3.73 GiB) file (or use the attached, zipped one):
$ cat /dev/zero | head -c 4001000000 > ~/Desktop/4gb
3. Try to copy this file to the target volume using Finder.
4. Try to copy this file to the target volume using cp.

Expected Results:
Both Finder and cp succeed in copying this file.

Observed Results:
Finder refuses to copy the file since it's larger than 4 GB.

Version:
macOS High Sierra 10.13 Beta (17A291m)

Notes:
Regression from OS X El Capitan, I believe. I haven't tried this in macOS Sierra.

Configuration:
Early 2015 MacBook Pro with Retina Display running macOS High Sierra 10.13 Beta (17A291m)

Comments


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