OpenBSD manual page server

Manual Page Search Parameters

FUSE_MOUNT(3) Library Functions Manual FUSE_MOUNT(3)

fuse_mount, fuse_unmountmount or dismount a FUSE file system

#include <fuse.h>

struct fuse_chan *
fuse_mount(const char *dir, struct fuse_args *args);

fuse_unmount(const char *dir, struct fuse_chan *ch);

The () function calls the mount(2) system call to graft the FUSE file system on to the file system tree at the point dir. args are FUSE specific mount options as documented by mount(2).

The following mount options can be specified by preceding them with -o, either individually or together separated by a comma.

Allow other users to access the file system. By default, FUSE will prevent other users from accessing the file system or to statfs(2) the file system. This security measure is particularly important for network file system that may expose private files. It also guards against system processes being blocked indefinitely if the file system stops responding.
Request that the kernel enforce file access permissions. Alternatively, FUSE file systems can choose to implement access checks internally. On OpenBSD, this option is always set.
Enables buffering of files in the kernel. Not recommended for file systems that can be updated external to FUSE, such as network file systems. Not implemented.
Specify the maximum size of read operations. Note that the kernel limits this to FUSEBUFMAXSIZE. This option should not be specified on the command line. The correct (or optimum) value depends on the filesystem implementation and should thus be specified by the filesystem internally.
Mount the file system read-only. Can also be specified by itself with -r.

() will attempt to unmount the file system mounted at dir by calling the unmount(2) system call. If this is successful, the kernel will send the FBT_DESTROY message to the file system, causing fuse_loop(3) to terminate. There is no way to determine whether this call was successful.

Only the super user can mount and unmount FUSE file systems.

fuse_main() will return NULL if the file system cannot be mounted.

fuse_mount() will fail when one of the following occurs: dir does not exist or is not a directory. The fuse device cannot be opened for reading and writing. There was an error parsing the options specified by args. The file system could not be mounted.

mount(2), fuse_main(3), fuse_setup(3), fuse(4)

The fuse_mount() and fuse_unmount() functions conforms to FUSE 2.6.

The fuse_mount() and fuse_unmount() functions first appeared in OpenBSD 5.4.

Sylvestre Gallon <>
Helg Bredow <>

July 8, 2018 OpenBSD-current