What are the common platform names in Buck?

I would like to build a cross-platform cxx_library with buck. I have different cpp files for the different platforms. According to the docs, I can handle this using platform_srcs, which is:

...a list of pairs where the first element is an un-anchored regex (in java.util.regex.Pattern syntax) against which the platform name is matched".

• What do these platform names look like?
• What are some example regexes I could use for OSX, Windows and Linux?

I am using the following:

• Android: android.*
• iPhone: iphoneos.*
• iPhone Simulator: iphonesimulator*
• Linux: linux.*
• macOS: macos.*
• Windows: windows.*

Don't forget to turn on should_remap_host_platform in order to avoid 'default' platform weirdness. In your .buckconfig:

[cxx]
  should_remap_host_platform = true

See: https://github.com/facebook/buck/issues/2073