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# buildah-unshare "1" "June 2018" "buildah"
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## NAME
buildah\-unshare - Run a command inside of a modified user namespace.
## SYNOPSIS
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**buildah unshare** [*options*] [**--**] [*command*]
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## DESCRIPTION
Launches a process (by default, *$SHELL* ) in a new user namespace. The user
namespace is configured so that the invoking user's UID and primary GID appear
to be UID 0 and GID 0, respectively. Any ranges which match that user and
group in /etc/subuid and /etc/subgid are also mapped in as themselves with the
help of the *newuidmap(1)* and *newgidmap(1)* helpers.
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buildah unshare is useful for troubleshooting unprivileged operations and for
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manually clearing storage and other data related to images and containers.
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It is also useful if you want to use the `buildah mount` command. If an unprivileged users wants to mount and work with a container, then they need to execute
buildah unshare. Executing `buildah mount` fails for unprivileged users unless the user is running inside a `buildah unshare` session.
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## OPTIONS
**--mount** [*VARIABLE=]containerNameOrID*
Mount the *containerNameOrID* container while running *command* , and set the
environment variable *VARIABLE* to the path of the mountpoint. If *VARIABLE*
is not specified, it defaults to *containerNameOrID* , which may not be a valid
name for an environment variable.
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## EXAMPLE
buildah unshare id
buildah unshare pwd
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buildah unshare cat /proc/self/uid\_map /proc/self/gid\_map
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buildah unshare rm -fr $HOME/.local/share/containers/storage /run/user/\`id -u\`/run
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buildah unshare --mount containerID sh -c 'cat ${containerID}/etc/os-release'
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If you want to use buildah with a mount command then you can create a script that looks something like:
```
cat buildah-script.sh < < _EOF
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#!/bin/sh
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ctr=$(buildah from scratch)
mnt=$(buildah mount $ctr)
dnf -y install --installroot=$mnt PACKAGES
dnf -y clean all --installroot=$mnt
buildah config --entrypoint="/bin/PACKAGE" --env "FOO=BAR" $ctr
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buildah commit $ctr imagename
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buildah unmount $ctr
_EOF
```
Then execute it with:
```
buildah unshare buildah-script.sh
```
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## SEE ALSO
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buildah(1), buildah-mount(1), namespaces(7), newuidmap(1), newgidmap(1), user\_namespaces(7)
