Command 'install' exits with unexpected error: install: link: ... to ...: File exists

[wq9578]

The utility install claims that a file exists although it didn't exist before.
In a shell script install is called with a filename argument based on a UTC timestamp:

ls -al /etc/chrony.conf.utc_*

-rw-r--r--  1 root  wheel  3806 Oct  7 01:47 /etc/chrony.conf.utc_2024_10_06_235200.bak
-rw-r--r--  1 root  wheel  3814 Oct  7 01:52 /etc/chrony.conf.utc_2024_10_06_235309.bak

install -bCSv -B .utc_2024_10_06_235355.bak -o root -g wheel -m u=rw,go=r /my/path/chrony.conf /etc/chrony.conf

install: /etc/chrony.conf -> /etc/chrony.conf.utc_2024_10_06_235355.bak
Error: a command has a non-zero exit status
install: link: /etc/chrony.conf to /etc/chrony.conf.utc_2024_10_06_235355.bak: File exists

My guess is that there might be an implementation problem when combining the options -b (backup) and -S (safe copy), such that the file is created by the utility itself, causing a collision.
The source used by current macOS 15.0.1 is taken from the FreeBSD source tree with the last commit here.
This line is the nearest code point I could find.

[markjdb]

This isn't the right place to report a MacOS bug.