as a little FYI for @BrockleyJohn and @burt
since I asked/posted about PHP7
1) I have read more about PHP7 changes in detail (especially the variable variables and execution order)
2) I decided it is all pretty low risk changes, I have not moved further to install on a raspberrypi, but I'm gonna be brave . Worst case, I just switch back to php 5.6, in 2 mins
3) I have checked out Johns PHP7 comp pack 02 branch onto my server and used BCompare to apply the changes in the code on the CATALOG side (all the relevant changes in the subdirectories, not the catalog pages themself as I have not integrated with Bootstrap)
4) I'm monitoring all errors on my live system to see if anything odd pops up (like multisafepay code seems to work, but is not fully compatible yet - depracated errors)
So far so good.
5) Started on the admin code, but again, can't find anything not working at this time on the admin side, just notices and deprecated warnings I need to cleanup in my custom code/modules
6) if you use APCu caching, apc_xxxx functions are no longer supported, need to change to apcu_xxx
What is the minimum required PHP version for responsive oscommerce, 5.x ?
Can we remove the specific php 4.x code pieces ?
KEEP CALM AND CARRY ON
FYI Upgrade to the highest PHP version you can( PHP 5.5/5.6 or 7.1 and get big performance improvements for free)
But be aware php 5.5 is more strict about things.
UTF8-without BOM, no extra spaces allowed at the beginning or end of your php file, or your redirects wont work.
No double declarations of functions allowed - used to slip through the cracks ...
Find the most frequent unique errors to fix:
grep "PHP" php_error_log.txt | sed "s/^.* PHP/PHP/g" |grep "line" |sort | uniq -c | sort -r > counterrors.txt