Are there file-naming conventions for .cron and .systemd extensions?

I’m starting to rename all my existing bash scripts in /home/Me/bin and /usr/local/bin from no extension to a .sh extension. The reason is the exact same file name with drastically different contents and purposes will sometimes exist in /etc/cron.d or /lib/systemd/system-sleep. This is causing false-positives with locate --regex '<file_name>' searches.

I’ve googled around and can’t find any file extension naming conventions for cron or systemd.

• If I went with DOS 8.3 conventions I would pick .crn and .syd
• If I went with 4 characters it I would pick .cron and .sysd
• If I went with 2 characters like .sh I would pick .cr and .sd

I’ve seen .py used for Python, .c for C program, .h for header file, .o for compiled object. This leads me to presume the Linux-verse would prefer two character extensions. I think the four character extensions are more readable. I don’t see any need for DOS 8.3 format since the old 8.x component is now 256.x in size or something like that. Systemd service files buck the “shorter-is-better” trend with .service files instead of .sr or .srv.

Before I go through the labour of renaming files and editing the parents that call the files with new names, are there any existing file extension conventions?

Note that if you or your organization has internal standards, that would be a perfectly acceptable answer, in absence of industry standards.

Just found a launchpad bug report where a user named a job /etc/cron.d/job.cron and it crashed due to the . in the name. The bug was filed in 2011 and confirmed, but still not fixed.

This means all my extensions will have to start with - instead of .