How do programs support i386 and ppc at the same time?

Question

I would like to know how you can support i386 and ppc architectures for programs in / bin.

I run for example

bin  $ file amber

I get

amber: setgid Mach-O universal binary with 2 architectures
amber (for architecture i386):  Mach-O executable i386
amber (for architecture ppc):   Mach-O executable ppc

How do programs support i386 and ppc in source code?

In other words, what components can you remove, for example, in / bin / amber if you remove ppc -architecture support?

Answer 1

Universal binary. , . Apple , , .

lipo . , , lipo .

, , ppc i386, " " . man- arch; , OSX, , ppc, ppc64, i386 x86_64. , , .

Answer 2

fat binary.

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