buildroot

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=== Customization _after_ the images have been created

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While post-build scripts (xref:rootfs-custom[]) are run _before_

building the filesystem image, kernel and bootloader, *post-image

scripts* can be used to perform some specific actions _after_ all images

have been created.

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Post-image scripts can for example be used to automatically extract your

root filesystem tarball in a location exported by your NFS server, or

to create a special firmware image that bundles your root filesystem and

kernel image, or any other custom action required for your project.

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To enable this feature, specify a space-separated list of post-image

scripts in config option +BR2_ROOTFS_POST_IMAGE_SCRIPT+ (in the +System

configuration+ menu). If you specify a relative path, it will be

relative to the root of the Buildroot tree.

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Just like post-build scripts, post-image scripts are run with the main

Buildroot tree as current working directory. The path to the +images+

output directory is passed as the first argument to each script. If the

config option +BR2_ROOTFS_POST_SCRIPT_ARGS+ is not empty, these

arguments will be passed to the script too. All the scripts will be

passed the exact same set of arguments, it is not possible to pass

different sets of arguments to each script.

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Again just like for the post-build scripts, the scripts have access to

the environment variables +BR2_CONFIG+, +HOST_DIR+, +STAGING_DIR+,

+TARGET_DIR+, +BUILD_DIR+, +BINARIES_DIR+ and +BASE_DIR+.

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The post-image scripts will be executed as the user that executes

Buildroot, which should normally _not_ be the root user. Therefore, any

action requiring root permissions in one of these scripts will require

special handling (usage of fakeroot or sudo), which is left to the

script developer.