One of the libraries that makes up my application depends on -undefined dynamic_lookup to link, and has since at least Snow Leopard if not earlier. I think iOS hasn't liked this for a while, but with the new linker I'm getting deprecation warnings even on OS X. I don't entirely understand what this flag does, other than it makes the build successful. :) So I'm at a loss on how to even approach fixing it. At this point, even links to useful resources would be appreciated, since googling hasn't yielded much beyond "remove -undefined to quiet the deprecation warning." FWIW, there is a bit of circular dependence between this library and another. On another OS, we need a carefully choreographed dance of building object files, then import libraries, then final linking to make this all work. So I suspect this may be related, but even if I'm correct, I don't know what would be the equivalent tools on Apple platforms.

On my MBP, I have two accounts, my main account and the "clean" account. (To simulate being a "normal" user, or for debugging purposes.) The "clean" account has no trouble connecting to my company WiFi, which uses a radius server. I'm not sure of the exact WiFi settings, but I could look it up in it really matters. My normal account can't connect to the server, in a really bizarre way. Every time I attempt to connected, it goes through the following steps Asks for a user name and password, as if I hadn't previously asked to store them. Asks me to import the certificate for the radius server, as if I can't see it list in Keychain Access. Among existing keys to use to use for the connection, it only lists my Developer Certificate keys. After going through all that and possibly entering my network username and password one more time, the WiFi bars in the status area are all lit up as if I'm connected. However, if you look at the network list underneath it, you see the indefinite progress indicator percolating next to the network name instead of WiFi bars, and I don't actually have access. After a while of that (at least 30 seconds if not longer), the situation flips. The bars next to the network name in the drop-down become sold active color, as if I'm connecting, but the WiFi bars in the status area start moving up and down as if connecting. I still have no network. Eventually, it disconnects, and reverts to whatever other network it can find. If I login to both accounts, connect from the "clean" account, and then fast user switch to my main account, the network disconnects. I don't know if that's a feature or a bug. Does anybody have any ideas on what could be going wrong and how to fix it? Or even ideas and how to debug what it's doing while spinning like crazy at me? Thanks!

Is there a way in pure C (not Objective-C, and certainly not Swift) way to detect if an iOS app is running on a Mac? I'm aware of iOSAppOnMac, but AFAICT I'd need to write Objective-C code to use it. My application is quite old and large, with portions going back to the 1980s, so the burden of moving on the anything that can't be accessible directly from C is quite high.

In Monterey, if your application executes python or python2.7, you will get a warning dialog that the python2 will be removed. However, this seems to happen only once. How can we reset the warning to make sure we're not accidentally triggering this on Monterey/

If you execute python3 and it is not pointing to an active developer tools, the user is prompted to install the command-line tools. Is there a way to test if python3 is actually available without triggering installation? (Our use case is that we would like to enumerate available python installs for the user to select from, without this accidentally triggering an install.)

Up until now, we have been using an optimized BLAS library for Intel processors. Now we are looking for replacements for Apple Silicon. I know that Accelerate provides such an interface. However, I haven't been able to find if it provides an ILP64, rather than LP64, interface, which is what we use on all 64-bit platforms. If it does, how do I access it? Thanks.