NAME
       ebuild  - the internal format, variables, and functions in
       an ebuild script

DESCRIPTION
       The ebuild(1) program accepts a single ebuild script as an
       argument.   This  script  contains  variables and commands
       that specify how  to  download,  unpack,  patch,  compile,
       install  and  merge a particular software package from its
       original sources.  In addition to all of this, the  ebuild
       script  can also contain pre/post install/remove commands,
       as required.

EXAMPLES
       Here's a simple example ebuild:

       DESCRIPTION="Super-useful stream editor (sed)"
       SRC_URI="ftp://alpha.gnu.org/pub/gnu/sed/${P}.tar.gz"
       HOMEPAGE="http://www.gnu.org/software/sed/sed.html"

       KEYWORDS="~x86"
       SLOT="0"
       LICENSE="GPL-2"
       IUSE=""

       DEPEND="virtual/glibc"
       RDEPEND="virtual/glibc"

       src_compile() {
            econf || die "could not configure"
            emake || die "emake failed"
       }

       src_install() {
            into /usr
            doinfo doc/sed.info
            doman doc/sed.1
            into /
            dobin sed/sed
            dodir /usr/bin
            dosym /bin/sed /usr/bin/sed
            dodoc  COPYING  NEWS README* THANKS TODO AUTHORS BUGS
       ANNOUNCE
       }

VARIABLES
       MISC USAGE NOTES
              - PORTAGE* and PORTDIR* variables may be  found  in
              make.conf(5).
              -  When  assigning  values to variables in ebuilds,
              you cannot have a space between the  variable  name
              and the equal sign.

       P      This variable contains the package name without the
              ebuild revision.  This variable must NEVER be modi­
              fied.
              xfree-4.2.1-r2.ebuild --> $P=='xfree-4.2.1'

       PN     Contains the name of the script without the version
              number.
              xfree-4.2.1-r2.ebuild --> $PN=='xfree'

       PV     Contains the version number without the revision.
              xfree-4.2.1-r2.ebuild --> $PV=='4.2.1'

       PR     Contains the revision number or 'r0' if no revision
              number exists.
              xfree-4.2.1-r2.ebuild --> $PR=='r2'

       PF     Contains the full package name [PN]-[PV]-r[PR]
              xfree-4.2.1-r2.ebuild --> $PF=='xfree-4.2.1-r2'

       A      Contains all source files required for the package.
              This variable must not be defined. It is autogener­
              ated from the SRC_URI variables.

       WORKDIR = "${PORTAGE_TMPDIR}/portage/${PF}/work"
              Contains  the  path  to the package build root.  Do
              not modify this variable.

       FILESDIR = "${PORTDIR}/${CATEGORY}/${PF}/files"
              Contains the path to the 'files' sub folder in  the
              package  specific location in the portage tree.  Do
              not modify this variable.

       S = "${WORKDIR}/${P}"
              Contains the path to the temporary build directory.
              This  variable is used by the functions src_compile
              and src_install.  Both are executed with S  as  the
              current  directory.   This variable may be modified
              to match the extraction directory of a tarball  for
              the package.

       T = "${PORTAGE_TMPDIR}/portage/${PF}/temp"
              Contains  the  path  to a temporary directory.  You
              may use this for whatever you like.

       D = "${PORTAGE_TMPDIR}/portage/${PF}/image"
              Contains the path to the temporary  install  direc­
              tory.   Every write operation that does not involve
              the helper tools and functions (found below) should
              be  prefixed  with  ${D}.  Do not modify this vari­
              able.

       DESCRIPTION = "A happy little package"
              Should contain a short description of the  package.

       SRC_URI = "http://happy.com/little/${P}.tar.gz"
              Contains  a  list  of URI's for the required source
              files.  It can contain multiple URI's for a  single
              source file.  The fastest location is chosen if the
              file was not found at GENTOO_MIRROR.

       HOMEPAGE = "http://happy.com/"
              Should contain a list of URL's for the sources main
              sites  and other further package dependent informa­
              tion.

       KEYWORDS = [-~][x86,ppc,sparc,mips,alpha,arm,hppa]
              Should contain appropriate list of arches that  the
              ebuild is know to work/not work.  By default if you
              do not know if an ebuild runs  under  a  particular
              arch  simply omit that KEYWORD.  If the ebuild will
              not work on that arch include it as -ppc for  exam­
              ple.   If  the ebuild is being submitted for inclu­
              sion, it must  have  ~arch  set  for  architectures
              where  it  has been PROVEN TO WORK.  (Packages KEY­
              WORDed this way may be unmasked for testing by set­
              ting  ACCEPT_KEYWORDS="~arch"  on the command line,
              or  in  make.conf(5))  For  an  authoritative  list
              please review /usr/portage/profiles/arch.list.

       SLOT   This  sets  the  SLOT for packages that may need to
              co-exist.   By  default  you  should  set  SLOT="0"
              unless  you  know what you are doing and need to do
              otherwise.  This value should NEVER be  left  unde­
              fined.

       LICENSE
              This  should  be a space delimited list of licenses
              that the package falls under.  This _must_  be  set
              to a matching license in /usr/portage/licenses/. If
              the license does not exist in portage yet you  must
              add it first.

       IUSE   This should be a list of any and all USE flags that
              are leveraged within your build script.   The  only
              USE  flags  that should not be listed here are arch
              related flags (see KEYWORDS).

       DEPEND This should contain a list of all packages that are
              required for the program to compile.

              DEPEND Atoms
                     A depend atom is simply a dependency that is
                     used by portage when  calculating  relation­
                     ships between packages.  Please note that if
                     the atom has not already been emerged,  then
                     the latest version available is matched.

                     Atom Bases
                             The  base  atom is just a full cate­
                             gory/packagename.  Hence, these  are
                             base atoms:

                             sys-apps/sed
                             sys-libs/zlib
                             net-misc/dhcp

                     Atom Versions
                             It  is  nice to be more specific and
                             say that only  certain  versions  of
                             atoms  are  acceptable.   Note  that
                             versions must  be  combined  with  a
                             prefix  (see  below).  Hence you may
                             add a version number as a postfix to
                             the base:

                             sys-apps/sed-4.0.5
                             sys-libs/zlib-1.1.4-r1
                             net-misc/dhcp-3.0_p2

                     Atom Prefix Operators [> >= = <= =]
                             Sometimes  you  want  to  be able to
                             depend on  general  versions  rather
                             than  specifying  exact versions all
                             the time.  Hence we provide standard
                             boolean operators:

                             >media-libs/libgd-1.6
                             >=media-libs/libgd-1.6
                             =media-libs/libgd-1.6
                             <=media-libs/libgd-1.6
                             <media-libs/libgd-1.6

                     Extended Atom Prefixes [!] and Postfixes [*]
                             Now  to get even fancier, we provide
                             the ability to define blocking pack­
                             ages  and  version  range  matching.
                             Also note that these  extended  pre­
                             fixes/postfixes  may  be combined in
                             any  way  with  the   atom   classes
                             defined above.  Here are some common
                             examples you may find in the portage
                             tree:

                             !app-text/dos2unix
                             =dev-libs/glib-2*
                             !net-fs/samba-2*

                             !  means  block  packages from being
                             installed at the same time.  * means
                             match  any version of the package so
                             long  as  the  specified   base   is
                             matched.  So with a version of '2*',
                             we can match '2.1', '2.2',  '2.2.1',
                             etc...  and not match version '1.0',
                             '3.0', '4.1', etc...

              USE Variation
                     Sometimes programs may depend  on  different
                     things  depending  on  the USE variable.  To
                     vary the packages the  program  depends  on,
                     just use this syntax:

                     DEPEND="media-libs/libsdl
                          jpeg? ( >=media-libs/jpeg-6b )
                          tiff? ( >=media-libs/tiff-3.5.5 )
                          png? ( >=media-libs/libpng-1.2.1 )
                          X? ( virtual/x11 )"


       RDEPEND
              This  should  contain  a  list of all
              packages that are required  for  this
              program  to run (aka runtime depend).
              If this is not set, then it  defaults
              to the value of DEPEND.
              You  may  use the same syntax to vary
              dependencies as seen above in DEPEND.

       RESTRICT = [nostrip,nomirror,fetch]
              This should be a space delimited list
              of portage features to restrict.
              nostrip
                     final binaries/libraries  will
                     not  be stripped of debug sym­
                     bols.
              nomirror
                     files in SRC_URI will  not  be
                     downloaded   from   the   GEN­
                     TOO_MIRRORS.
              fetch  like nomirror  but  the  files
                     will   not   be   fetched  via
                     SRC_URI either.

       PROVIDE = "virtual/TARGET"
              This variable  should  only  be  used
              when  a  package  provides  a virtual
              target.  For  example,  blackdown-jdk
              and   sun-jdk   provide  virtual/jdk.
              This allows for packages to depend on
              virtual/jdk  rather than on blackdown
              or sun specifically.

FUNCTIONS
       pkg_nofetch
              If you turn  on  fetch  in  RESTRICT,
              then  this  function will be run when
              the files in SRC_URI cannot be found.
              Useful  for displaying information to
              the user  on  *how*  to  obtain  said
              files.

       pkg_setup
              This  function  can  be  used  if the
              package needs specific setup  actions
              or checks to be preformed before any­
              thing else.
              Initial    working    directory    of
              ${PORTAGE_TMPDIR}.

       src_unpack
              This  function  is used to unpack all
              the sources in A to WORKDIR.  If  not
              defined in the ebuild script it calls
              unpack ${A}. Any  patches  and  other
              pre  configure/compile  modifications
              should be done here.
              Initial    working    directory    of
              $WORKDIR.

       src_compile
              All necessary steps for configuration
              and compilation  should  be  done  in
              here.
              Initial working directory of $S.

       src_install
              Should contain everything required to
              install the package in the  temporary
              install directory.
              Initial working directory of $S.

       pkg_preinst pkg_postinst
              All  modifications  required  on  the
              live-filesystem before and after  the
              package  is  merged  should be placed
              here. Also commentary  for  the  user
              should  be  listed here as it will be
              displayed last.
              Initial working directory of $PWD.

       pkg_prerm pkg_postrm
              Like the pkg_*inst functions but  for
              unmerge.
              Initial working directory of $PWD.

       config This function should contain optional
              basic configuration steps.
              Initial working directory of $PWD.

HELPER FUNCTIONS: GENERAL
       die [reason]
              Causes the current emerge process  to
              be  aborted.  The  final display will
              include reason.

       use <USE item>
              If USE item is in the  USE  variable,
              USE item will be echoed and the func­
              tion will return 0.  If USE  item  is
              not in the USE variable, the function
              will return 1.

              Example:
                     if [ `use gnome` ] ; then
                          guiconf="--enable-
                     gui=gnome --with-x"
                     elif [ `use gtk` ] ; then
                          guiconf="--enable-gui=gtk
                     --with-x"
                     elif [ `use X` ] ; then
                          guiconf="--enable-
                     gui=athena --with-x"
                     else
                          #  No gui version will be
                     built
                          guiconf=""
                     fi

       use_with <USE item> [configure option]
              Useful for creating custom options to
              pass  to  a  configure script. If USE
              item is in the USE variable, then the
              string --with-[configure option] will
              be echoed.  If USE item is not in the
              USE variable, then the string --with­
              out-[configure   option]   will    be
              echoed.   If  configure option is not
              specified, than USE item will be used
              in its place.

              Example:
                     USE="jpeg"
                     myconf="`use_with   jpeg  lib­
                     jpeg`"
                     (myconf  now  has  the   value
                     "--with-libjpeg")

                     USE=""
                     myconf="`use_with   jpeg  lib­
                     jpeg`"
                     (myconf  now  has  the   value
                     "--without-libjpeg")

                     USE="pic"
                     myconf="`use_with pic`"
                     (myconf   now  has  the  value
                     "--with-pic")

       use_enable <USE item> [configure option]
              Useful for creating custom options to
              pass  to  a  configure script. If USE
              item is in the USE variable, then the
              string   --enable-[configure  option]
              will be echoed.  If USE item  is  not
              in  the USE variable, then the string
              --disable-[configure option] will  be
              echoed.  If  configure  option is not
              specified, than USE item will be used
              in its place.
              See use_with for an example.

       has <item> <item list>
              If item is in item list, then item is
              echoed and has returns 0.  Otherwise,
              nothing  is echoed and 1 is returned.
              The item list is delimited by the IFS
              variable.    This   variable   has  a
              default value of ' ', or a space.  It
              is a bash(1) setting.

       has_version <category/package-version>
              Check to see if category/package-ver­
              sion is installed on the system.  The
              parameter accepts all values that are
              acceptable in  the  DEPEND  variable.
              The   function  returns  0  if  cate­
              gory/package-version is installed,  1
              otherwise.

       best_version <package name>
              This  function  will  look up package
              name in  the  database  of  currently
              installed programs and echo the "best
              version" of the package that is  cur­
              rently   installed.    The   function
              returns 0 if there is a package  that
              matches package name.  Otherwise, the
              function will return 1.

              Example:
                     VERINS=`best_version      net-
                     ftp/glftpd`
                     (VERINS   now  has  the  value
                     "net-ftp/glftpd-1.27"       if
                     glftpd-1.27 is installed)

HELPER FUNCTIONS: UNPACK
       unpack <source> [list of more sources]
              This   function  uncompresses  and/or
              untars a list  of  sources  into  the
              current  directory. The function will
              append source to  the  DISTDIR  vari­
              able.

HELPER FUNCTIONS: COMPILE
       econf [configure options]
              This  is  used  as  a replacement for
              configure.  Performs:
              configure \
                   --prefix=/usr \
                   --host=${CHOST} \
                   --mandir=/usr/share/man \
                   --infodir=/usr/share/info \
                   --datadir=/usr/share \
                   --sysconfdir=/etc \
                   --localstatedir=/var/lib \
                   configure options

              *Note: There is no need  to  use  '||
              die' because econf checks for you

       emake [make options]
              This  is  used  as  a replacement for
              make.     Performs     default     is
              MAKEOPTS="-j2".

              ***warning***
              if  you  are going to use emake, make
              sure your build is  happy  with  par­
              alell makes (make -j2).  It should be
              tested thoroughly as  parallel  makes
              are notorious for failing _sometimes_
              but not always.

              *Note: Be sure to use '||  die'  con­
              structs to ensure emake success

HELPER FUNCTIONS: INSTALL
       einstall [make options]
              This  is  used  as  a replacement for
              make install.  Performs:
              make prefix=${D}/usr \
                          mandir=${D}/usr/share/man
              \
                          infodir=${D}/usr/share/info
              \
                          datadir=${D}/usr/share \
                          sysconfdir=${D}/etc \
                          localstate­
              dir=${D}/var/lib \
                          make options install

              *Note:  There  is  no need to use '||
              die' because einstall checks for you

       prepall
       prepalldocs
       prepallinfo
       prepallman
       prepallstrip
              Useful for when  a  package  installs
              into  ${D}  via  scripts  (i.e. make­
              files).  If you want to be sure  that
              libraries   are  executable,  aclocal
              files are installed  into  the  right
              place,  doc/info/man  files  are  all
              compressed, and that executables  are
              all  stripped  of  debugging symbols,
              then use these suite of functions.
              prepall:
                     Runs prepallman,  prepallinfo,
                     prepallstrip,  sets  libraries
                     +x, and  then  checks  aclocal
                     directories.  Please note this
                     does *not* run prepalldocs.
              prepalldocs:
                     Compresses all  doc  files  in
                     ${D}/usr/share/doc.
              prepallinfo:
                     Compresses  all  info files in
                     ${D}/usr/share/info.
              prepallman:
                     Compresses all  man  files  in
                     ${D}/usr/share/man.
              prepallstrip:
                     Strips all executable files of
                     debugging   symboles.     This
                     includes libraries.

       prepinfo [dir]
       preplib [dir]
       preplib.so [dir]
       prepman [dir]
       prepstrip [dir]
              Similiar  to  the  prepall functions,
              these are  subtle  in  their  differ­
              ences.
              prepinfo:
                     If  a  dir  is  not specified,
                     then prepinfo will assume  the
                     dir  usr.  prepinfo  will then
                     compress  all  the  files   in
                     ${D}/dir/info.
              preplib:
                     If  a  dir  is  not specified,
                     then preplib will  assume  the
                     dir usr. preplib will then run
                     'ldconfig    -n     -N'     on
                     ${D}/dir/lib.
              preplib.so:
                     All  the  files  with '.so' in
                     their name and  are  found  in
                     ${D}/dir  will  be stripped of
                     their debug symbols.  You  may
                     specify  multiple directories.
              prepman:
                     If a  dir  is  not  specified,
                     then  prepman  will assume the
                     dir  usr.  prepman  will  then
                     compress   all  the  files  in
                     ${D}/dir/man/*/.
              prepstrip:
                     All   the   files   found   in
                     ${D}/dir   will  be  stripped.
                     You   may   specify   multiple
                     directories.

       dopython <commands>
              Performs  commands  with  python  and
              returns the result.

       dosed "s:orig:change:g" <filename>
              Performs sed (including  cp/mv  file­
              name) on filename.
              'dosed          "s:/usr/local:/usr:g"
              /usr/bin/some-script'  runs  sed   on
              ${D}/usr/bin/some-script

       dodir <path>
              Creates a directory inside of ${D}.
              'dodir /usr/lib/apache'       creates
              ${D}/usr/lib/apache

       into <path>
              Sets the root  (DESTTREE)  for  other
              functions  like dobin, dosbin, doman,
              doinfo, dolib.
              The default root is /usr.

       keepdir <path>
              Tells portage to  leave  a  directory
              behind   even   if   it   is   empty.
              Functions the same as dodir.

       dobin <binary> [list of more binaries]
              Installs a binary or a list of  bina­
              ries  into DESTTREE/bin.  Creates all
              necessary dirs.

       dosbin <binary> [list of more binaries]
              Installs a binary or a list of  bina­
              ries into DESTTREE/sbin.  Creates all
              necessary dirs.

       dolib <library> [list of more libraries]
       dolib.a <library> [list of more libraries]
       dolib.so <library> [list of more libraries]
              Installs  a  library  or  a  list  of
              libraries into DESTTREE/lib.  Creates
              all necessary dirs.

       doman <man-page> [list of more man-pages]
              Installs  manual-pages   into   DEST­
              DIR/man/man[1-8n]  depending  on  the
              manual file  ending.  The  files  are
              gzipped if they are not already. Cre­
              ates all necessary dirs.

       dohard <filename> <linkname>
       dosym <filename> <linkname>
              Performs the ln command as  either  a
              hard link or symlink.

       dohtml      [-a    filetypes]    [-r]    [-x
       list-of-dirs-to-ignore]
       [list-of-files-and-dirs]
              Installs  the  files  in  the list of
              files  (space-separated  list)   into
              /usr/share/doc/${PF}/html    provided
              the file ends in .html, .png, .js, -A
              appends  to the default list, setting
              -x sets which dirs  to  exclude  (CVS
              excluded  by default), -r sets recur­
              sive.

       doinfo <info-file> [list of more info-files]
              Installs   info-pages   into    DEST­
              DIR/info.   Files  are  automatically
              gzipped.  Creates all necessary dirs.

       dojar <jar file> [list of more jar files]
              Installs      jar      files     into
              /usr/share/${PN}/lib and adds them to
              /usr/share/${PN}/classpath.env.

       domo    <locale-file>    [list    of    more
       locale-files]
              Installs   locale-files   into  DEST­
              DIR/usr/share/locale/[LANG] depending
              on  local-file's ending.  Creates all
              necessary dirs.

       fowners <permissions> <file> [files]
       fperms <permissions> <file> [files]
              Performs  chown  (fowners)  or  chmod
              (fperms),   applying  permissions  to
              files.

       insinto [path]
              Sets the root (INSDESTTREE)  for  the
              doins function.
              The default root is /.

       insopts [options for install(1)]
              Can be used to define options for the
              install function used in doins.   The
              default is -m0644.

       doins <file> [list of more files]
              Installs   files   into  INSDESTTREE.
              This function uses install(1).

       exeinto [path]
              Sets the root (EXEDESTTREE)  for  the
              doexe function.
              The default root is /.

       exeopts [options for install(1)]
              Can be used to define options for the
              install function used in doexe.   The
              default is -m0755.

       doexe  <executable>  [list  of more executa­
       bles]
              Installs  a  executable  or a list of
              executable  into  EXEDESTTREE.   This
              function uses install(1).

       docinto [path]
              Sets  the  relative  subdir (DOCDEST­
              TREE) used by dodoc.

       dodoc <document> [list of more documents]
              Installs a document or a list of doc­
              ument   into  /usr/doc/${PV}/DOCDEST­
              TREE.    Files   are    automatically
              gzipped.  Creates all necessary dirs.

       newbin <old file> <new filename>
       newsbin <old file> <new filename>
       newlib <old file> <new filename>
       newlib.so <old file> <new filename>
       newlib.a <old file> <new filename>
       newman <old file> <new filename>
       newinfo <old file> <new filename>
       newins <old file> <new filename>
       newexe <old file> <new filename>
       newdoc <old file> <new filename>
              All these functions act like the  do*
              functions,  but  they  only work with
              one file and the file is installed as
              [new filename].

REPORTING BUGS
       Please   report  bugs  via  http://bugs.gen­
       too.org/

SEE ALSO
       ebuild(1), make.conf(5)

       The /usr/sbin/ebuild.sh script.

       The helper apps in /usr/lib/portage/bin.

FILES
       /etc/make.conf
              Contains variables for the build-pro­
              cess    and   overwrites   those   in
              make.defaults.

       /etc/make.globals
              Contains the  default  variables  for
              the  build-process,  you  should edit
              /etc/make.conf instead.

AUTHORS
       Achim Gottinger <achim@gentoo.org>
       Mark Guertin <gerk@gentoo.org>
       Nicholas Jones <carpaski@gentoo.org>
       Mike Frysinger <vapier@gentoo.org>