Provided by: dpkg-dev_1.18.4ubuntu1_all bug

NAME

       dpkg-architecture - set and determine the architecture for package building

SYNOPSIS

       dpkg-architecture [option...] [command]

DESCRIPTION

       dpkg-architecture provides a facility to determine and set the build and host architecture
       for package building.

       The build architecture is always determined by an external call to dpkg(1), and can not be
       set at the command line.

       You  can specify the host architecture by providing one or both of the options --host-arch
       and --host-type. The default is determined by an external call to gcc(1), or the  same  as
       the  build  architecture  if  CC or gcc are both not available. One out of --host-arch and
       --host-type is sufficient, the value of the other will be set to a usable default. Indeed,
       it  is  often  better to only specify one, because dpkg-architecture will warn you if your
       choice does not match the default.

COMMANDS

       -l, --list
              Print the environment variables, one each line, in the format VARIABLE=value.  This
              is the default action.

       -e, --equal architecture
              Check  for  equality of architecture (since dpkg 1.13.13).  It compares the current
              or specified Debian host architecture against architecture, to check  if  they  are
              equal.   This  action will not expand the architecture wildcards.  Command finishes
              with an exit status of 0 if matched, 1 if not matched.

       -i, --is architecture-wildcard
              Check for identity of architecture (since dpkg 1.13.13).  It compares  the  current
              or  specified  Debian  host architecture against architecture-wildcard after having
              expanded it as an architecture wildcard, to check if they match.  Command  finishes
              with an exit status of 0 if matched, 1 if not matched.

       -q, --query variable-name
              Print the value of a single variable.

       -s, --print-set
              Print  an  export  command. This can be used to set the environment variables using
              eval.

       -u, --print-unset
              Print a similar command to --print-unset but to unset all variables.

       -c, --command command
              Execute a command in an environment which has all variables set to  the  determined
              value.

       -L, --list-known
              Print  a  list  of valid architecture names.  Possibly restricted by one or more of
              the matching options --match-wildcard, --match-bits or --match-endian  (since  dpkg
              1.17.14).

       -?, --help
              Show the usage message and exit.

       --version
              Show the version and exit.

OPTIONS

       -a, --host-arch architecture
              Set the host Debian architecture.

       -t, --host-type gnu-system-type
              Set the host GNU system type.

       -A, --target-arch architecture
              Set the target Debian architecture (since dpkg 1.17.14).

       -T, --target-type gnu-system-type
              Set the target GNU system type (since dpkg 1.17.14).

       -W, --match-wildcard architecture-wildcard
              Restrict  the  architectures  listed by --list-known to ones matching the specified
              architecture wildcard (since dpkg 1.17.14).

       -B, --match-bits architecture-bits
              Restrict the architectures listed by --list-known to ones with  the  specified  CPU
              bits (since dpkg 1.17.14). Either 32 or 64.

       -E, --match-endian architecture-endianness
              Restrict  the  architectures  listed  by  --list-known  to  ones with the specified
              endianness (since dpkg 1.17.14). Either little or big.

       -f, --force
              Values set by existing environment variables with the same  name  as  used  by  the
              scripts  are honored (i.e. used by dpkg-architecture), except if this force flag is
              present. This  allows  the  user  to  override  a  value  even  when  the  call  to
              dpkg-architecture    is    buried    in    some    other    script   (for   example
              dpkg-buildpackage(1)).

TERMS

       build machine
           The machine the package is built on.

       host machine
           The machine the package is built for.

       target machine
           The machine the compiler is building for.  This is only needed when building a  cross-
           toolchain,  one  that  will  be built on the build architecture, to be run on the host
           architecture, and to build code for the target architecture.

       Debian architecture
           The Debian architecture string, which specifies the binary tree in  the  FTP  archive.
           Examples: i386, sparc, hurd-i386.

       Debian architecture wildcard
           A  Debian  architecture  wildcard is a special architecture string that will match any
           real architecture being part of it. The general  form  is  <kernel>-<cpu>.   Examples:
           linux-any, any-i386, hurd-any.

       GNU system type
           An  architecture  specification  string consisting of two parts separated by a hyphen:
           cpu and system.  Examples: i586-linux-gnu, sparc-linux-gnu, i686-gnu, x86_64-netbsd.

       multiarch triplet
           The clarified GNU system type, used for  filesystem  paths.   This  triplet  does  not
           change  even when the baseline ISA gets bumped, so that the resulting paths are stable
           over time.  The only current difference with the GNU system type is that the CPU  part
           for  i386  based  systems is always i386.  Examples: i386-linux-gnu, x86_64-linux-gnu.
           Example paths: /lib/powerpc64le-linux-gnu/, /usr/lib/i386-kfreebsd-gnu/.

VARIABLES

       The following variables are set by dpkg-architecture:

       DEB_BUILD_ARCH
           The Debian architecture of the build machine.

       DEB_BUILD_ARCH_OS
           The Debian system name of the build machine (since dpkg 1.13.2).

       DEB_BUILD_ARCH_CPU
           The Debian cpu name of the build machine (since dpkg 1.13.2).

       DEB_BUILD_ARCH_BITS
           The pointer size of the build machine (in bits; since dpkg 1.15.4).

       DEB_BUILD_ARCH_ENDIAN
           The endianness of the build machine (little / big; since dpkg 1.15.4).

       DEB_BUILD_GNU_CPU
           The CPU part of DEB_BUILD_GNU_TYPE.

       DEB_BUILD_GNU_SYSTEM
           The System part of DEB_BUILD_GNU_TYPE.

       DEB_BUILD_GNU_TYPE
           The GNU system type of the build machine.

       DEB_BUILD_MULTIARCH
           The clarified GNU system type of the build machine, used for filesystem  paths  (since
           dpkg 1.16.0).

       DEB_HOST_ARCH
           The Debian architecture of the host machine.

       DEB_HOST_ARCH_OS
           The Debian system name of the host machine (since dpkg 1.13.2).

       DEB_HOST_ARCH_CPU
           The Debian cpu name of the host machine (since dpkg 1.13.2).

       DEB_HOST_ARCH_BITS
           The pointer size of the host machine (in bits; since dpkg 1.15.4).

       DEB_HOST_ARCH_ENDIAN
           The endianness of the host machine (little / big; since dpkg 1.15.4).

       DEB_HOST_GNU_CPU
           The CPU part of DEB_HOST_GNU_TYPE.

       DEB_HOST_GNU_SYSTEM
           The System part of DEB_HOST_GNU_TYPE.

       DEB_HOST_GNU_TYPE
           The GNU system type of the host machine.

       DEB_HOST_MULTIARCH
           The  clarified  GNU  system type of the host machine, used for filesystem paths (since
           dpkg 1.16.0).

       DEB_TARGET_ARCH
           The Debian architecture of the target machine (since dpkg 1.17.14).

       DEB_TARGET_ARCH_OS
           The Debian system name of the target machine (since dpkg 1.17.14).

       DEB_TARGET_ARCH_CPU
           The Debian cpu name of the target machine (since dpkg 1.17.14).

       DEB_TARGET_ARCH_BITS
           The pointer size of the target machine (in bits; since dpkg 1.17.14).

       DEB_TARGET_ARCH_ENDIAN
           The endianness of the target machine (little / big; since dpkg 1.17.14).

       DEB_TARGET_GNU_CPU
           The CPU part of DEB_TARGET_GNU_TYPE (since dpkg 1.17.14).

       DEB_TARGET_GNU_SYSTEM
           The System part of DEB_TARGET_GNU_TYPE (since dpkg 1.17.14).

       DEB_TARGET_GNU_TYPE
           The GNU system type of the target machine (since dpkg 1.17.14).

       DEB_TARGET_MULTIARCH
           The clarified GNU system type of the target machine, used for filesystem paths  (since
           dpkg 1.17.14).

FILES

   Architecture tables
       All  these  files  have to be present for dpkg-architecture to work. Their location can be
       overridden at runtime with the environment variable DPKG_DATADIR.

       /usr/share/dpkg/cputable
              Table of known CPU names and mapping to their GNU name.

       /usr/share/dpkg/ostable
              Table of known operating system names and mapping to their GNU name.

       /usr/share/dpkg/triplettable
              Mapping between Debian architecture triplets and Debian architecture names.

       /usr/share/dpkg/abitable
              Table of Debian architecture ABI attribute overrides.

   Packaging support
       /usr/share/dpkg/architecture.mk
              Makefile  snippet  that  properly  sets  and  exports  all   the   variables   that
              dpkg-architecture outputs (since dpkg 1.16.1).

EXAMPLES

       dpkg-buildpackage  accepts  the  -a  option  and  passes  it  to  dpkg-architecture. Other
       examples:

              CC=i386-gnu-gcc dpkg-architecture -c debian/rules build

              eval `dpkg-architecture -u`

       Check if the current or specified host architecture is equal to an architecture:

              dpkg-architecture -elinux-alpha

              dpkg-architecture -amips -elinux-mips

       Check if the current or specified host architecture is a Linux system:

              dpkg-architecture -ilinux-any

              dpkg-architecture -ai386 -ilinux-any

   Usage in debian/rules
       The environment variables set by dpkg-architecture are  passed  to  debian/rules  as  make
       variables  (see  make documentation). However, you should not rely on them, as this breaks
       manual invocation of  the  script.  Instead,  you  should  always  initialize  them  using
       dpkg-architecture  with the -q option. Here are some examples, which also show how you can
       improve the cross compilation support in your package:

       Retrieving the GNU system type and forwarding it to ./configure:

           DEB_BUILD_GNU_TYPE ?= $(shell dpkg-architecture -qDEB_BUILD_GNU_TYPE)
           DEB_HOST_GNU_TYPE ?= $(shell dpkg-architecture -qDEB_HOST_GNU_TYPE)
           [...]
           ifeq ($(DEB_BUILD_GNU_TYPE), $(DEB_HOST_GNU_TYPE))
             confflags += --build=$(DEB_HOST_GNU_TYPE)
           else
             confflags += --build=$(DEB_BUILD_GNU_TYPE) \
                          --host=$(DEB_HOST_GNU_TYPE)
           endif
           [...]
           ./configure $(confflags)

       Doing something only for a specific architecture:

           DEB_HOST_ARCH ?= $(shell dpkg-architecture -qDEB_HOST_ARCH)

           ifeq ($(DEB_HOST_ARCH),alpha)
             [...]
           endif

       or if you  only  need  to  check  the  CPU  or  OS  type,  use  the  DEB_HOST_ARCH_CPU  or
       DEB_HOST_ARCH_OS variables.

       Note  that  you  can  also  rely  on  an external Makefile snippet to properly set all the
       variables that dpkg-architecture can provide:

           include /usr/share/dpkg/architecture.mk

           ifeq ($(DEB_HOST_ARCH),alpha)
             [...]
           endif

       In  any  case,  you  should  never  use  dpkg  --print-architecture  to  get  architecture
       information during a package build.

NOTES

       All long command and option names available only since dpkg 1.17.17.

SEE ALSO

       dpkg-buildpackage(1), dpkg-cross(1).