dpkg-architecture(1)            dpkg utilities            dpkg-architecture(1)



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

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

DESCRIPTION
       dpkg-architecture does provide 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-architec-
       ture 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  vari-
              ables.

       -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. 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.

       -T, --target-type gnu-system-type
              Set the target GNU system type.

       -W, --match-wildcard architecture-wildcard
              Restrict the architectures listed by --list-known to ones match-
              ing 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-architec-
              ture),  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-buildpack-
              age(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.

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

       architecture wildcard
           An 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 sepa-
           rated by  a  hyphen:  cpu  and  system.  Examples:  i386-linux-gnu,
           sparc-linux-gnu, i386-gnu, x86_64-netbsd.

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 archi-
              tecture names.

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

EXAMPLES
       dpkg-buildpackage accepts the -a option and passes it to dpkg-architec-
       ture. 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-architec-
       ture  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).



Debian Project                    2013-03-28              dpkg-architecture(1)
