ebuild(5): USE dependency defaults in EAPI 4

diff --git a/man/ebuild.5 b/man/ebuild.5
index 6b4364bdf556dea7bc13408e6b8e732b695919cc..22cec1761d5d39aaa43f466e4384b8576334a383 100644 (file)
--- a/man/ebuild.5
+++ b/man/ebuild.5
@@ -346,6 +346,21 @@ foo[bar=]  bar? ( foo[bar] ) !bar? ( foo[\-bar] )
 foo[!bar=]     bar? ( foo[\-bar] ) !bar? ( foo[bar] )
 .TE
 .RE
+.TP
+.B Atom USE defauts
+Beginning with \fBEAPI 4\fR, \fBUSE\fR dependencies may specify default
+assumptions about values for flags that may or may not be missing from
+the \fBIUSE\fR of the matched package. Such defaults are specified by
+immediately following a flag with either \fB(+)\fR or \fB(\-)\fR. Use
+\fB(+)\fR to behave as if a missing flag is present and enabled, or
+\fB(\-)\fR to behave as if it is present and disabled:
+
+.RS
+.nf
+media\-video/ffmpeg[threads(+)]
+media\-video/ffmpeg[threads(\-)]
+.fi
+.RE
 .RE
 .TP
 .B Dynamic DEPENDs