An Apple Library Primer
Apple’s library technology has a long and glorious history, dating all the way back to the origins of Unix. This does, however, mean that it can be a bit confusing to newcomers. This is my attempt to clarify some terminology.
[…]
The linker has seen three major implementations:
ld— This dates from the dawn of Mac OS X.
ld64— This was a rewrite started in the 2005 timeframe. Eventually it replacedldcompletely. If you typeld, you getld64.
ld_prime— This was introduced with Xcode 15. This isn’t a separate tool. Rather,ldnow supports the-ld_classicand-ld_newoptions to select a specific implementation.[…]
The dynamic linker has seen 4 major revisions. See WWDC 2017 Session 413 (referenced below) for a discussion of versions 1 through 3. Version 4 is basically a merging of versions 2 and 3.
Previously:
>Note The older talks are no longer available from Apple, but you may be able to find transcripts out there on the ’net.
Historically Apple published a document, Mac OS X ABI Mach-O File Format Reference, or some variant thereof, that acted as the definitive reference to the Mach-O file format. This document is no longer available from Apple. If you’re doing serious work with Mach-O, I recommend that you find an old copy.
What an exemplary commitment to reliable and enduring developer support, Apple.