Provided by: dpkg-dev_1.22.11ubuntu1_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 either the DEB_BUILD_ARCH variable if set
       (and --force not being specified) or by an external call to dpkg(1), and cannot 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, otherwise the DEB_HOST_ARCH variable is used if set (and --force not
       being specified).  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 the
           POSIX shell or make eval, depending on the output format.

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

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

           If the command-string contains shell metacharacters, then it will be invoked through
           the system bourne shell.

       -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.

       --print-format format
           Sets the output format for --print-set and --print-unset (since dpkg 1.20.6), to
           either shell (default) or make.

       -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, or the emulator will run code for.  This is
           only needed when building a cross-toolchain (or emulator), one that will be built on
           the build architecture, to be run on the host architecture, and to build (or run
           emulated) 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 tuple
           A Debian architecture tuple is the fully qualified architecture with all its
           components spelled out.  This differs with Debian architectures in that at least the
           cpu component does not embed the abi.  The current tuple has the form abi-libc-os-cpu.
           Examples: base-gnu-linux-amd64, eabihf-musl-linux-arm.

       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 a Debian architecture tuple
           with four or less elements, and with at least one of them being any.  Missing elements
           of the tuple are prefixed implicitly as any, and thus the following pairs are
           equivalent:

           any-any-any-any = any
           any-any-os-any = os-any
           any-libc-any-any = libc-any-any

           Examples: linux-any, any-i386, hurd-any, eabi-any-any-arm, musl-any-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 read from the environment (unless --force has been specified)
       and set by dpkg-architecture (see the TERMS section for a description of the naming
       scheme):

       DEB_BUILD_ARCH
           The Debian architecture of the build machine.

       DEB_BUILD_ARCH_ABI
           The Debian ABI name of the build machine (since dpkg 1.18.11).

       DEB_BUILD_ARCH_LIBC
           The Debian libc name of the build machine (since dpkg 1.18.11).

       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 GNU CPU part of DEB_BUILD_GNU_TYPE.

       DEB_BUILD_GNU_SYSTEM
           The GNU 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_ABI
           The Debian ABI name of the host machine (since dpkg 1.18.11).

       DEB_HOST_ARCH_LIBC
           The Debian libc name of the host machine (since dpkg 1.18.11).

       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 GNU CPU part of DEB_HOST_GNU_TYPE.

       DEB_HOST_GNU_SYSTEM
           The GNU 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_ABI
           The Debian ABI name of the target machine (since dpkg 1.18.11).

       DEB_TARGET_ARCH_LIBC
           The Debian libc name of the target machine (since dpkg 1.18.11).

       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 GNU CPU part of DEB_TARGET_GNU_TYPE (since dpkg 1.17.14).

       DEB_TARGET_GNU_SYSTEM
           The GNU 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.  These tables contain a
       format Version pseudo-field on their first line to mark their format, so that parsers can
       check if they understand it, such as "# Version=1.0".

       /usr/share/dpkg/cputable
           Table of known CPU names and mapping to their GNU name.  Format version 1.0 (since
           dpkg 1.13.2).

       /usr/share/dpkg/ostable
           Table of known operating system names and mapping to their GNU name.  Format version
           2.0 (since dpkg 1.18.11).

       /usr/share/dpkg/tupletable
           Mapping between Debian architecture tuples and Debian architecture names.  Format
           version 1.0 (since dpkg 1.18.11).

       /usr/share/dpkg/abitable
           Table of Debian architecture ABI attribute overrides.  Format version 2.0 (since dpkg
           1.18.11).

   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.

ENVIRONMENT

       DPKG_DATADIR
           If set, it will be used as the dpkg data directory, where the architecture tables are
           located (since dpkg 1.14.17).  Defaults to «/usr/share/dpkg».

       DPKG_COLORS
           Sets the color mode (since dpkg 1.18.5).  The currently accepted values are: auto
           (default), always and never.

       DPKG_NLS
           If set, it will be used to decide whether to activate Native Language Support, also
           known as internationalization (or i18n) support (since dpkg 1.19.0).  The accepted
           values are: 0 and 1 (default).

NOTES

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

SEE ALSO

       dpkg-buildpackage(1).