These include the large middle-class suburbs of Peoria, Mesa, Chandler, and Glendale; upscale Scottsdale; and the college area of Tempe which serves as home to Arizona State University. All areas are modern and generally lacking in historic interest, but keep in mind that Phoenix only had 100,000 residents in 1950.
do {} until ($false) is an infinite loop; it'll only exit if you use something like break, return or throw from inside the loop body. do { } until ($true) would execute the loop body exactly once (which would make the loop rather pointless.) It looks like what you intended to do was wait for a file to exist.
We do not use will after until when speaking about the future. I'll stay here until you come back. We have to wait until he arrives. When we use a negative construction (with not) in the main clause, until means 'not before'. I won't (will not) start cooking until you come home. (= 'not before you come home') I can't (cannot) read the newspaper until I find my glasses. We sometimes use the constructions have + past participle and had + past participle with until.