new* helpers can read from stdin

Did you know that new* helpers can read from stdin? Well, now you know! So instead of writing to a temporary file you can install your inline text straight to the destination:

src_install() {
  # old code
  cat <<-EOF >"${T}"/mywrapper || die
    #!/bin/sh
    exec do-something --with-some-argument
  EOF
  dobin "${T}"/mywrapper

  # replacement
  newbin - mywrapper <<-EOF
    #!/bin/sh
    exec do-something --with-some-argument
  EOF
}

Inlining path_exists

The path_exists function in eutils was meant as a simple hack to check for existence of files matching a wildcard. However, it was kinda ugly and never became used widely. At this very moment, it is used correctly in three packages, semi-correctly in one package and totally misused in two packages. Therefore, I think it’s time to replace it with something nicer.

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Empty directories, *into, dodir, keepdir and tmpfiles.d

There seems to be some serious confusion around the way directories are installed in Gentoo. In this post, I would like to shortly explain the differences between different methods of creating directories in ebuilds, and instruct how to handle the issues related to installing empty directories and volatile locations.

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The ultimate guide to EAPI 7

Back when EAPI 6 was approved and ready for deployment, I have written a blog post entitled the Ultimate Guide to EAPI 6. Now that EAPI 7 is ready, it is time to publish a similar guide to it.

Of all EAPIs approved so far, EAPI 7 brings the largest number of changes. It follows the path established by EAPI 6. It focuses on integrating features that are either commonly used or that can not be properly implemented in eclasses, and removing those that are either deemed unnecessary or too complex to support. However, the circumstances of its creation are entirely different.

EAPI 6 was more like a minor release. It was formed around the time when Portage development has been practically stalled. It aimed to collect some old requests into an EAPI that would be easy to implement by people with little knowledge of Portage codebase. Therefore, the majority of features oscillated around bash parts of the package manager.

EAPI 7 is closer to a proper major release. It included some explicit planning ahead of specification, and the specification has been mostly completed even before the implementation work started. We did not initially skip features that were hard to implement, even though the hardest of them were eventually postponed.

I will attempt to explain all the changes in EAPI 7 in this guide, including the rationale and ebuild code examples.

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