guestunmount - Online in the Cloud

PROGRAM:

NAME

guestunmount - Unmount a guestmounted filesystem

SYNOPSIS

guestunmount mountpoint

guestunmount --fd=<FD> mountpoint

DESCRIPTION

guestunmount is a utility to clean up mounted filesystems automatically. guestmount(1)
mounts filesystems using libguestfs. This program unmounts the filesystem when a program
or script has finished with it.

guestunmount is a wrapper around the FUSE fusermount(1) program, which must exist on the
current "PATH".

There are two ways to use guestunmount. When called as:

guestunmount mountpoint

it unmounts "mountpoint" immediately.

When called as:

guestunmount --fd=FD mountpoint

it waits until the pipe "FD" is closed. This can be used to monitor another process and
clean up its mountpoint when that process exits, as described below.

FROM PROGRAMS
You can just call "guestunmount mountpoint" from the program, but a more sophisticated way
to use guestunmount is to have it monitor your program so it can clean up the mount point
if your program exits unexpectedly.

In the program, create a pipe (eg. by calling pipe(2)). Let "FD" be the file descriptor
number of the read side of the pipe (ie. "pipefd[0]").

After mounting the filesystem with guestmount(1) (on "mountpoint"), fork and run
guestunmount like this:

guestunmount --fd=FD mountpoint

Close the read side of the pipe in the parent process.

Now, when the write side of the pipe (ie. "pipefd[1]") is closed for any reason, either
explicitly or because the parent process exits, guestunmount notices and unmounts the
mountpoint.

If your operating system supports it, you should set the "FD_CLOEXEC" flag on the write
side of the pipe. This is so that other child processes don't inherit the file descriptor
and keep it open.

Guestunmount never daemonizes itself.

FROM SHELL SCRIPTS
Since bash doesn't provide a way to create an unnamed pipe, use a trap to call
guestunmount on exit like this:

trap "guestunmount mountpoint" EXIT INT QUIT TERM

OPTIONS

--fd=FD
Specify the pipe file descriptor to monitor, and delay cleanup until that pipe is
closed.

--help
Display brief help and exit.

-q
--quiet
Don't display error messages from fusermount. The return status is still set (see
"EXIT STATUS" below).

--no-retry
--retry=N
By default, guestunmount will retry the fusermount operation up to 5 times (that is,
it will run it up to 6 times = 1 try + 5 retries).

Use --no-retry to make guestunmount run fusermount only once.

Use --retry=N to make guestunmount retry "N" times instead of 5.

guestunmount performs an exponential back-off between retries, waiting 1 second,
2 seconds, 4 seconds, etc before each retry.

-V
--version
Display the program version and exit.

ENVIRONMENT VARIABLES

"PATH"
The fusermount(1) program (supplied by FUSE) must be available on the current "PATH".

EXIT STATUS

This program returns 0 if successful, or one of the following error codes:

1 Program error, eg. could not allocate memory, could not run fusermount. See the error
message printed for more information.

2 The mount point could not be unmounted even after retrying. See the error message
printed for the underlying fusermount error.

3 The mount point is not mounted.

Use guestunmount online using onworks.net services