"virtual/libc" shouldn't be used in {,R}DEPEND example (as mentioned in Bug #174260).
"sys-libs/zlib" also shouldn't be used because it belongs to system set.
Also http://www.gentoo.org/proj/en/devrel/handbook/handbook.xml?part=3&chap=1#doc_chap5.
betelgeuse@pena ~/proj-en/devrel/handbook $ cvs diff Index: hb-guide-ebuild.xml =================================================================== RCS file: /var/cvsroot/gentoo/xml/htdocs/proj/en/devrel/handbook/hb-guide-ebuild.xml,v retrieving revision 1.43 diff -u -r1.43 hb-guide-ebuild.xml --- hb-guide-ebuild.xml 23 Jun 2007 19:59:14 -0000 1.43 +++ hb-guide-ebuild.xml 16 Sep 2007 20:13:35 -0000 @@ -1952,21 +1952,21 @@ </p> <pre caption="Depend example"> -DEPEND="virtual/libc - sys-libs/zlib" -RDEPEND="virtual/libc" +DEPEND="virtual/opengl + dev-libs/libxml2" +RDEPEND="${DEPEND}" </pre> <p> This tells Portage that to build <path>foo-x.y.z</path>, the packages -<path>virtual/libc</path> (more on virtuals in a bit) and -<path>sys-libs/zlib</path> are needed. It does not say anything about which -version of glibc or zlib that are needed, which means "anything goes". +<path>virtual/opengl</path> (more on virtuals in a bit) and +<path>dev-lib/libxml2</path> are needed. It does not say anything about which +version of opengl or libxml2 that are needed, which means "anything goes". </p> <p> The "anything goes" is of course a bit scary, and will not work in the general -case. But for central libraries like glibc, which strives very hard to be 100% +case. But for libraries, which strive very hard to be 100% binary compatible all the time, it actually works. For other libraries, we can of course specify version dependencies. </p> Index: hb-policy-ebuild.xml =================================================================== RCS file: /var/cvsroot/gentoo/xml/htdocs/proj/en/devrel/handbook/hb-policy-ebuild.xml,v retrieving revision 1.19 diff -u -r1.19 hb-policy-ebuild.xml --- hb-policy-ebuild.xml 27 Mar 2007 21:35:14 -0000 1.19 +++ hb-policy-ebuild.xml 16 Sep 2007 20:13:35 -0000 @@ -639,8 +639,7 @@ <pre caption="Example of RDEPEND"> RDEPEND="${DEPEND} - net-ftp/curl - virtual/libc" + net-ftp/curl" </pre> <p>