FreeBSD's chmod(1) and chmod(2) can't set sticky bit to non-directories not in jail. (ufschmod in sys/ufs/ufs/ufs_vnops.c)
But manpages doesn't describe about it.
How-To-Repeat: % touch /tmp/a % chmod +t /tmp/a chmod: /tmp/a: Inappropriate file type or format
From 4.4BSD as a historical reference:
The ISVTX (the sticky bit) indicates to the system which executable files
are shareable (the default) and the system maintains the program text of
the files in the swap area. The sticky bit may only be set by the super
user on shareable executable files.
Though, it has long obsolete since then.
For bugs matching the following criteria:
Status: In Progress Changed: (is less than) 2014-06-01
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