# Build Variables

Setting Host and Target

During the building of the cross-compile tools you will need to set a few variables that will be dependent on your particular needs. You will need to set the target triplet for the target architecture, and the CPU type. If you do not know what triplet or CPU type you want, you can use the table as a reference. Set the command using the method listed below:

    export CLFS_HOST=$(echo ${MACHTYPE} | sed "s/-[^-]*/-cross/")
    export CLFS_TARGET=[target triplet]
    export CLFS_CPU=[cpu type]

## Processor Type and Target Triplets

Processor | Target Triplet | CPU Type | Note
486 Compatibles | i486-linux-musl | i486 | Intel's i486
Pentium, K6, 586 Compatibles | i586-linux-musl | i586 | Intel Pentium without MMX
Pentium II, Pentium III, Pentium 4 | i686-linux-musl | i686 | PentiumPro instruction set
Athlon | i686-linux-musl | athlon | AMD 32 bit Athlon
Opteron | x86_64-linux-musl | k8 | AMD K8 processors with x86-64

Now set the architecture of the CPU:

    export CLFS_ARCH="x86"

Now we will add this to `~/.bashrc`, just in case you have to exit and restart building later:

    echo export CLFS_HOST=\""${CLFS_HOST}\"" >> ~/.bashrc
    echo export CLFS_TARGET=\""${CLFS_TARGET}\"" >> ~/.bashrc
    echo export CLFS_ARCH=\""${CLFS_ARCH}\"" >> ~/.bashrc
    echo export CLFS_CPU=\""${CLFS_CPU}\"" >> ~/.bashrc