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Can anyone explain the following piece of code from the syscall package in the Go standard library?
// /usr/local/Cellar/go/1.10/libexec/src/syscall/syscall.go
//
//
// Getpagesize and Exit are provided by the runtime
func Getpagesize() int
func Exit(code int)
There is no function body and also it is not an interface. What is it then?
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The Go Programming Language Specification
A function declaration may omit the body. Such a declaration provides the signature for a function implemented outside Go, such as an assembly routine.
Read the documentation.