Re: rsync --delete

[David <bouncingcats@gmail.com>]

On Tue, 20 Oct 2020 at 14:11, David Christensen
<dpchrist@holgerdanske.com> wrote:
> On 2020-10-19 04:55, Greg Wooledge wrote:
> > On Sat, Oct 17, 2020 at 03:01:13PM -0700, David Christensen wrote:

> >> I try to use all lower case letters for variable names and all upper case
> >> letters for constants.

> > ALL_UPPER_CASE is reserved for internal shell variables, and environment
> > variables.

> Please provide a citation (for Bourne shell scripts).

Maybe POSIX.1-2017 is what you're asking for?

https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap01.html
"""
POSIX.1-2017 defines a standard operating system interface and
environment, including a command interpreter (or "shell"), and
common utility programs to support applications portability at the
source code level.
"""

https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html
"""
Environment variable names used by the utilities in the Shell and Utilities
volume of POSIX.1-2017 consist solely of uppercase letters, digits, and
the <underscore> ( '_' )
[...]
The name space of environment variable names containing lowercase
letters is reserved for applications.
[...]
It is unwise to conflict with certain variables that are frequently exported
by widely used command interpreters and applications:
[...]
"""