The getProcessEntry code is currently duplicated in https://github.com/inconshreveable/mousetrap, which is widely used in projects (commonly as dependency for spf13/cobra). Until recently, mousetrap had code for backward-compatibility with old Go versions, but now that that code was removed, it's a very small wrapper around getProcessEntry. Exporting this function allows mousetrap to not having to duplicate the code, or for projects currently depending on mousetrap to consume the golang.org/x/sys code directly (most projects would already have golang.org/x/sys as dependency in some form or another).

Looking at the history for getProcessEntry, I see that this function was originally contributed by the author of Mousetrap (as a helper for Getppid(); see 6f6f1bd / https://codereview.appspot.com/102320044), and there have been no changes since its inception. From that perspective, I estimate it won't add additional maintenance costs to the x/sys project.

• relates to windows: export getProcessEntry sys#143 / https://go-review.googlesource.com/c/sys/+/459039
• relates to remove support for go1.3 inconshreveable/mousetrap#7 (comment)