I'm confused on one of the ksh93 test qualifiers that we use. Twenty+ years ago we took a "Unix Shell Programming - featuring the KornShell" course. In the manual that accompanied that course it says that "-a filename" will be successful if the file exists. We've used "-a" extensively since that time. I recently came across this link that says "-a" is a 'binary AND operator' for testing (we are using ksh93 on AIX 7.1), and 'man test' shows the same output as the link.
Now that link seems to be a general AIX link. That is, it's not obvious to me that it's specific to ksh, csh, sh, etc, so I'm not sure how it applies.
It does appear that our existing code works as expected. Here's an example of how we currently use it.
if [[ -a filename ]] then .... fi
I realize that there are other qualifiers for testing files, but I'm wondering why "-a" seems to check for existence while the manpage suggests it doesn't.
Thanks in advance.