git: 00f6c1be84 - main - Porter's Handbook: Document Uses=elfctl

The branch main has been updated by jrm (ports committer):

URL: https://cgit.FreeBSD.org/doc/commit/?id=00f6c1be842bbf1b20a91c10d250ae082f1fd826

commit 00f6c1be842bbf1b20a91c10d250ae082f1fd826
Author:     Joseph Mingrone <jrm@FreeBSD.org>
AuthorDate: 2022-03-15 18:16:11 +0000
Commit:     Joseph Mingrone <jrm@FreeBSD.org>
CommitDate: 2022-03-15 19:07:11 +0000

    Porter's Handbook: Document Uses=elfctl
    
    Approved by:    docs (debdrup)
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D34570
---
 .../en/books/porters-handbook/uses/_index.adoc     | 23 ++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/documentation/content/en/books/porters-handbook/uses/_index.adoc b/documentation/content/en/books/porters-handbook/uses/_index.adoc
index cfeb56a9ac..0052b18ebe 100644
--- a/documentation/content/en/books/porters-handbook/uses/_index.adoc
+++ b/documentation/content/en/books/porters-handbook/uses/_index.adoc
@@ -373,6 +373,29 @@ Possible arguments: 2, 3, build (default), run
 
 Add dependency on package:math/eigen[].
 
+[[uses-elfctl]]
+== `elfctl`
+
+Possible arguments: (none)
+
+Change an ELF binary's feature control note by setting ELF_FEATURES.
+
+[[uses-elfct-ex1]]
+.Uses=elfctl
+[example]
+====
+[.programlisting]
+....
+USES=           elfctl
+ELF_FEATURES=	featurelist:path/to/file1 \
+		featurelist:path/to/file1 \
+		featurelist:path/to/file2
+....
+
+====
+
+The format of `featurelist` is described in man:elfctl[1].  The file paths are relative to ${BUILD_WRKSRC}.
+
 [[uses-fakeroot]]
 == `fakeroot`