alcove

@doc mount(2): mount a filesystem, Linux style

The arguments are:

• source

• target

• filesystem type

• flags

• data

An empty list may be used to specify NULL.

For example, filesystems mounted in a Linux mount namespace may be
visible in the global mount namespace. To avoid this, first remount the
root filesystem within a mount namespace using the MS_REC|MS_PRIVATE flags:

```
{ok, Task} = alcove:clone(Drv, [], [clone_newns]),
ok = alcove:mount(Drv, [Task], "none", "/", [], [ms_rec, ms_private], []).
'''

On BSD systems, the `Source' argument is ignored and passed to the system
mount call as:

```
mount(FSType, Target, Flags, Data);
'''

On Solaris, some mount options are passed in the Options argument as a
string of comma separated values terminated by a NULL.  Other platforms
ignore the Options parameter.

== Examples ==

An example of bind mounting a directory within a linux mount namespace:

```
1> {ok, Drv} = alcove_drv:start([{exec, "sudo -n"}]).
{ok,<0.177.0>}
2> {ok, Pid} = alcove:clone(Drv, [], [clone_newns]).
{ok,10059}
3> alcove:mount(Drv, [Pid], "/tmp", "/mnt", "", [ms_bind, ms_rdonly, ms_noexec], "", "").
ok
4> alcove:umount(Drv, [Pid], "/mnt").
ok
'''