fuse
Data Fields
fuse_lowlevel_ops Struct Reference

#include <fuse_lowlevel.h>

Data Fields

void(* init )(void *userdata, struct fuse_conn_info *conn)
 
void(* destroy )(void *userdata)
 
void(* lookup )(fuse_req_t req, fuse_ino_t parent, const char *name)
 
void(* forget )(fuse_req_t req, fuse_ino_t ino, unsigned long nlookup)
 
void(* getattr )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 
void(* setattr )(fuse_req_t req, fuse_ino_t ino, struct stat *attr, int to_set, struct fuse_file_info *fi)
 
void(* readlink )(fuse_req_t req, fuse_ino_t ino)
 
void(* mknod )(fuse_req_t req, fuse_ino_t parent, const char *name, mode_t mode, dev_t rdev)
 
void(* mkdir )(fuse_req_t req, fuse_ino_t parent, const char *name, mode_t mode)
 
void(* unlink )(fuse_req_t req, fuse_ino_t parent, const char *name)
 
void(* rmdir )(fuse_req_t req, fuse_ino_t parent, const char *name)
 
void(* symlink )(fuse_req_t req, const char *link, fuse_ino_t parent, const char *name)
 
void(* rename )(fuse_req_t req, fuse_ino_t parent, const char *name, fuse_ino_t newparent, const char *newname)
 
void(* link )(fuse_req_t req, fuse_ino_t ino, fuse_ino_t newparent, const char *newname)
 
void(* open )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 
void(* read )(fuse_req_t req, fuse_ino_t ino, size_t size, off_t off, struct fuse_file_info *fi)
 
void(* write )(fuse_req_t req, fuse_ino_t ino, const char *buf, size_t size, off_t off, struct fuse_file_info *fi)
 
void(* flush )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 
void(* release )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 
void(* fsync )(fuse_req_t req, fuse_ino_t ino, int datasync, struct fuse_file_info *fi)
 
void(* opendir )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 
void(* readdir )(fuse_req_t req, fuse_ino_t ino, size_t size, off_t off, struct fuse_file_info *fi)
 
void(* releasedir )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)
 
void(* fsyncdir )(fuse_req_t req, fuse_ino_t ino, int datasync, struct fuse_file_info *fi)
 
void(* statfs )(fuse_req_t req, fuse_ino_t ino)
 
void(* setxattr )(fuse_req_t req, fuse_ino_t ino, const char *name, const char *value, size_t size, int flags)
 
void(* getxattr )(fuse_req_t req, fuse_ino_t ino, const char *name, size_t size)
 
void(* listxattr )(fuse_req_t req, fuse_ino_t ino, size_t size)
 
void(* removexattr )(fuse_req_t req, fuse_ino_t ino, const char *name)
 
void(* access )(fuse_req_t req, fuse_ino_t ino, int mask)
 
void(* create )(fuse_req_t req, fuse_ino_t parent, const char *name, mode_t mode, struct fuse_file_info *fi)
 
void(* getlk )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi, struct flock *lock)
 
void(* setlk )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi, struct flock *lock, int sleep)
 
void(* bmap )(fuse_req_t req, fuse_ino_t ino, size_t blocksize, uint64_t idx)
 
void(* ioctl )(fuse_req_t req, fuse_ino_t ino, int cmd, void *arg, struct fuse_file_info *fi, unsigned flags, const void *in_buf, size_t in_bufsz, size_t out_bufsz)
 
void(* poll )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi, struct fuse_pollhandle *ph)
 
void(* write_buf )(fuse_req_t req, fuse_ino_t ino, struct fuse_bufvec *bufv, off_t off, struct fuse_file_info *fi)
 
void(* retrieve_reply )(fuse_req_t req, void *cookie, fuse_ino_t ino, off_t offset, struct fuse_bufvec *bufv)
 
void(* forget_multi )(fuse_req_t req, size_t count, struct fuse_forget_data *forgets)
 
void(* flock )(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi, int op)
 
void(* fallocate )(fuse_req_t req, fuse_ino_t ino, int mode, off_t offset, off_t length, struct fuse_file_info *fi)
 
void(* readdirplus )(fuse_req_t req, fuse_ino_t ino, size_t size, off_t off, struct fuse_file_info *fi)
 

Detailed Description

Low level filesystem operations

Most of the methods (with the exception of init and destroy) receive a request handle (fuse_req_t) as their first argument. This handle must be passed to one of the specified reply functions.

This may be done inside the method invocation, or after the call has returned. The request handle is valid until one of the reply functions is called.

Other pointer arguments (name, fuse_file_info, etc) are not valid after the call has returned, so if they are needed later, their contents have to be copied.

The filesystem sometimes needs to handle a return value of -ENOENT from the reply function, which means, that the request was interrupted, and the reply discarded. For example if fuse_reply_open() return -ENOENT means, that the release method for this file will not be called.

Field Documentation

void(* fuse_lowlevel_ops::access)(fuse_req_t req, fuse_ino_t ino, int mask)

Check file access permissions

This will be called for the access() system call. If the 'default_permissions' mount option is given, this method is not called.

This method is not called under Linux kernel versions 2.4.x

Introduced in version 2.5

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
maskrequested access mode
void(* fuse_lowlevel_ops::bmap)(fuse_req_t req, fuse_ino_t ino, size_t blocksize, uint64_t idx)

Map block index within file to block index within device

Note: This makes sense only for block device backed filesystems mounted with the 'blkdev' option

Introduced in version 2.6

Valid replies: fuse_reply_bmap fuse_reply_err

Parameters
reqrequest handle
inothe inode number
blocksizeunit of block index
idxblock index within file
void(* fuse_lowlevel_ops::create)(fuse_req_t req, fuse_ino_t parent, const char *name, mode_t mode, struct fuse_file_info *fi)

Create and open a file

If the file does not exist, first create it with the specified mode, and then open it.

Open flags (with the exception of O_NOCTTY) are available in fi->flags.

Filesystem may store an arbitrary file handle (pointer, index, etc) in fi->fh, and use this in other all other file operations (read, write, flush, release, fsync).

There are also some flags (direct_io, keep_cache) which the filesystem may set in fi, to change the way the file is opened. See fuse_file_info structure in <fuse_common.h> for more details.

If this method is not implemented or under Linux kernel versions earlier than 2.6.15, the mknod() and open() methods will be called instead.

Introduced in version 2.5

Valid replies: fuse_reply_create fuse_reply_err

Parameters
reqrequest handle
parentinode number of the parent directory
nameto create
modefile type and mode with which to create the new file
fifile information
void(* fuse_lowlevel_ops::destroy)(void *userdata)

Clean up filesystem

Called on filesystem exit

There's no reply to this function

Parameters
userdatathe user data passed to fuse_lowlevel_new()
void(* fuse_lowlevel_ops::fallocate)(fuse_req_t req, fuse_ino_t ino, int mode, off_t offset, off_t length, struct fuse_file_info *fi)

Allocate requested space. If this function returns success then subsequent writes to the specified range shall not fail due to the lack of free space on the file system storage media.

Introduced in version 2.9

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
offsetstarting point for allocated region
lengthsize of allocated region
modedetermines the operation to be performed on the given range, see fallocate(2)
void(* fuse_lowlevel_ops::flock)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi, int op)

Acquire, modify or release a BSD file lock

Note: if the locking methods are not implemented, the kernel will still allow file locking to work locally. Hence these are only interesting for network filesystems and similar.

Introduced in version 2.9

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
opthe locking operation, see flock(2)
void(* fuse_lowlevel_ops::flush)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)

Flush method

This is called on each close() of the opened file.

Since file descriptors can be duplicated (dup, dup2, fork), for one open call there may be many flush calls.

Filesystems shouldn't assume that flush will always be called after some writes, or that if will be called at all.

fi->fh will contain the value set by the open method, or will be undefined if the open method didn't set any value.

NOTE: the name of the method is misleading, since (unlike fsync) the filesystem is not forced to flush pending writes. One reason to flush data, is if the filesystem wants to return write errors.

If the filesystem supports file locking operations (setlk, getlk) it should remove all locks belonging to 'fi->owner'.

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
void(* fuse_lowlevel_ops::forget)(fuse_req_t req, fuse_ino_t ino, unsigned long nlookup)

Forget about an inode

This function is called when the kernel removes an inode from its internal caches.

The inode's lookup count increases by one for every call to fuse_reply_entry and fuse_reply_create. The nlookup parameter indicates by how much the lookup count should be decreased.

Inodes with a non-zero lookup count may receive request from the kernel even after calls to unlink, rmdir or (when overwriting an existing file) rename. Filesystems must handle such requests properly and it is recommended to defer removal of the inode until the lookup count reaches zero. Calls to unlink, remdir or rename will be followed closely by forget unless the file or directory is open, in which case the kernel issues forget only after the release or releasedir calls.

Note that if a file system will be exported over NFS the inodes lifetime must extend even beyond forget. See the generation field in struct fuse_entry_param above.

On unmount the lookup count for all inodes implicitly drops to zero. It is not guaranteed that the file system will receive corresponding forget messages for the affected inodes.

Valid replies: fuse_reply_none

Parameters
reqrequest handle
inothe inode number
nlookupthe number of lookups to forget
void(* fuse_lowlevel_ops::forget_multi)(fuse_req_t req, size_t count, struct fuse_forget_data *forgets)

Forget about multiple inodes

See description of the forget function for more information.

Introduced in version 2.9

Valid replies: fuse_reply_none

Parameters
reqrequest handle
void(* fuse_lowlevel_ops::fsync)(fuse_req_t req, fuse_ino_t ino, int datasync, struct fuse_file_info *fi)

Synchronize file contents

If the datasync parameter is non-zero, then only the user data should be flushed, not the meta data.

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
datasyncflag indicating if only data should be flushed
fifile information
void(* fuse_lowlevel_ops::fsyncdir)(fuse_req_t req, fuse_ino_t ino, int datasync, struct fuse_file_info *fi)

Synchronize directory contents

If the datasync parameter is non-zero, then only the directory contents should be flushed, not the meta data.

fi->fh will contain the value set by the opendir method, or will be undefined if the opendir method didn't set any value.

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
datasyncflag indicating if only data should be flushed
fifile information
void(* fuse_lowlevel_ops::getattr)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)

Get file attributes

Valid replies: fuse_reply_attr fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifor future use, currently always NULL
void(* fuse_lowlevel_ops::getlk)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi, struct flock *lock)

Test for a POSIX file lock

Introduced in version 2.6

Valid replies: fuse_reply_lock fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
lockthe region/type to test
void(* fuse_lowlevel_ops::getxattr)(fuse_req_t req, fuse_ino_t ino, const char *name, size_t size)

Get an extended attribute

If size is zero, the size of the value should be sent with fuse_reply_xattr.

If the size is non-zero, and the value fits in the buffer, the value should be sent with fuse_reply_buf.

If the size is too small for the value, the ERANGE error should be sent.

Valid replies: fuse_reply_buf fuse_reply_data fuse_reply_xattr fuse_reply_err

Parameters
reqrequest handle
inothe inode number
nameof the extended attribute
sizemaximum size of the value to send
void(* fuse_lowlevel_ops::init)(void *userdata, struct fuse_conn_info *conn)

Initialize filesystem

Called before any other filesystem method

There's no reply to this function

Parameters
userdatathe user data passed to fuse_lowlevel_new()
void(* fuse_lowlevel_ops::ioctl)(fuse_req_t req, fuse_ino_t ino, int cmd, void *arg, struct fuse_file_info *fi, unsigned flags, const void *in_buf, size_t in_bufsz, size_t out_bufsz)

Ioctl

Note: For unrestricted ioctls (not allowed for FUSE servers), data in and out areas can be discovered by giving iovs and setting FUSE_IOCTL_RETRY in . For restricted ioctls, kernel prepares in/out data area according to the information encoded in cmd.

Introduced in version 2.8

Valid replies: fuse_reply_ioctl_retry fuse_reply_ioctl fuse_reply_ioctl_iov fuse_reply_err

Parameters
reqrequest handle
inothe inode number
cmdioctl command
argioctl argument
fifile information
flagsfor FUSE_IOCTL_* flags
in_bufdata fetched from the caller
in_bufsznumber of fetched bytes
out_bufszmaximum size of output data
void(* fuse_lowlevel_ops::link)(fuse_req_t req, fuse_ino_t ino, fuse_ino_t newparent, const char *newname)

Create a hard link

Valid replies: fuse_reply_entry fuse_reply_err

Parameters
reqrequest handle
inothe old inode number
newparentinode number of the new parent directory
newnamenew name to create
void(* fuse_lowlevel_ops::listxattr)(fuse_req_t req, fuse_ino_t ino, size_t size)

List extended attribute names

If size is zero, the total size of the attribute list should be sent with fuse_reply_xattr.

If the size is non-zero, and the null character separated attribute list fits in the buffer, the list should be sent with fuse_reply_buf.

If the size is too small for the list, the ERANGE error should be sent.

Valid replies: fuse_reply_buf fuse_reply_data fuse_reply_xattr fuse_reply_err

Parameters
reqrequest handle
inothe inode number
sizemaximum size of the list to send
void(* fuse_lowlevel_ops::lookup)(fuse_req_t req, fuse_ino_t parent, const char *name)

Look up a directory entry by name and get its attributes.

Valid replies: fuse_reply_entry fuse_reply_err

Parameters
reqrequest handle
parentinode number of the parent directory
namethe name to look up
void(* fuse_lowlevel_ops::mkdir)(fuse_req_t req, fuse_ino_t parent, const char *name, mode_t mode)

Create a directory

Valid replies: fuse_reply_entry fuse_reply_err

Parameters
reqrequest handle
parentinode number of the parent directory
nameto create
modewith which to create the new file
void(* fuse_lowlevel_ops::mknod)(fuse_req_t req, fuse_ino_t parent, const char *name, mode_t mode, dev_t rdev)

Create file node

Create a regular file, character device, block device, fifo or socket node.

Valid replies: fuse_reply_entry fuse_reply_err

Parameters
reqrequest handle
parentinode number of the parent directory
nameto create
modefile type and mode with which to create the new file
rdevthe device number (only valid if created file is a device)
void(* fuse_lowlevel_ops::open)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)

Open a file

Open flags (with the exception of O_CREAT, O_EXCL, O_NOCTTY and O_TRUNC) are available in fi->flags.

Filesystem may store an arbitrary file handle (pointer, index, etc) in fi->fh, and use this in other all other file operations (read, write, flush, release, fsync).

Filesystem may also implement stateless file I/O and not store anything in fi->fh.

There are also some flags (direct_io, keep_cache) which the filesystem may set in fi, to change the way the file is opened. See fuse_file_info structure in <fuse_common.h> for more details.

Valid replies: fuse_reply_open fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
void(* fuse_lowlevel_ops::opendir)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)

Open a directory

Filesystem may store an arbitrary file handle (pointer, index, etc) in fi->fh, and use this in other all other directory stream operations (readdir, releasedir, fsyncdir).

Filesystem may also implement stateless directory I/O and not store anything in fi->fh, though that makes it impossible to implement standard conforming directory stream operations in case the contents of the directory can change between opendir and releasedir.

Valid replies: fuse_reply_open fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
void(* fuse_lowlevel_ops::poll)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi, struct fuse_pollhandle *ph)

Poll for IO readiness

Introduced in version 2.8

Note: If ph is non-NULL, the client should notify when IO readiness events occur by calling fuse_lowelevel_notify_poll() with the specified ph.

Regardless of the number of times poll with a non-NULL ph is received, single notification is enough to clear all. Notifying more times incurs overhead but doesn't harm correctness.

The callee is responsible for destroying ph with fuse_pollhandle_destroy() when no longer in use.

Valid replies: fuse_reply_poll fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
phpoll handle to be used for notification
void(* fuse_lowlevel_ops::read)(fuse_req_t req, fuse_ino_t ino, size_t size, off_t off, struct fuse_file_info *fi)

Read data

Read should send exactly the number of bytes requested except on EOF or error, otherwise the rest of the data will be substituted with zeroes. An exception to this is when the file has been opened in 'direct_io' mode, in which case the return value of the read system call will reflect the return value of this operation.

fi->fh will contain the value set by the open method, or will be undefined if the open method didn't set any value.

Valid replies: fuse_reply_buf fuse_reply_iov fuse_reply_data fuse_reply_err

Parameters
reqrequest handle
inothe inode number
sizenumber of bytes to read
offoffset to read from
fifile information
void(* fuse_lowlevel_ops::readdir)(fuse_req_t req, fuse_ino_t ino, size_t size, off_t off, struct fuse_file_info *fi)

Read directory

Send a buffer filled using fuse_add_direntry(), with size not exceeding the requested size. Send an empty buffer on end of stream.

fi->fh will contain the value set by the opendir method, or will be undefined if the opendir method didn't set any value.

Returning a directory entry from readdir() does not affect its lookup count.

Valid replies: fuse_reply_buf fuse_reply_data fuse_reply_err

Parameters
reqrequest handle
inothe inode number
sizemaximum number of bytes to send
offoffset to continue reading the directory stream
fifile information
void(* fuse_lowlevel_ops::readdirplus)(fuse_req_t req, fuse_ino_t ino, size_t size, off_t off, struct fuse_file_info *fi)

Read directory with attributes

Send a buffer filled using fuse_add_direntry_plus(), with size not exceeding the requested size. Send an empty buffer on end of stream.

fi->fh will contain the value set by the opendir method, or will be undefined if the opendir method didn't set any value.

In contrast to readdir() (which does not affect the lookup counts), the lookup count of every entry returned by readdirplus() is increased by one.

Introduced in version 3.0

Valid replies: fuse_reply_buf fuse_reply_data fuse_reply_err

Parameters
reqrequest handle
inothe inode number
sizemaximum number of bytes to send
offoffset to continue reading the directory stream
fifile information
void(* fuse_lowlevel_ops::readlink)(fuse_req_t req, fuse_ino_t ino)

Read symbolic link

Valid replies: fuse_reply_readlink fuse_reply_err

Parameters
reqrequest handle
inothe inode number
void(* fuse_lowlevel_ops::release)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)

Release an open file

Release is called when there are no more references to an open file: all file descriptors are closed and all memory mappings are unmapped.

For every open call there will be exactly one release call.

The filesystem may reply with an error, but error values are not returned to close() or munmap() which triggered the release.

fi->fh will contain the value set by the open method, or will be undefined if the open method didn't set any value. fi->flags will contain the same flags as for open.

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
void(* fuse_lowlevel_ops::releasedir)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi)

Release an open directory

For every opendir call there will be exactly one releasedir call.

fi->fh will contain the value set by the opendir method, or will be undefined if the opendir method didn't set any value.

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
void(* fuse_lowlevel_ops::removexattr)(fuse_req_t req, fuse_ino_t ino, const char *name)

Remove an extended attribute

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
nameof the extended attribute
void(* fuse_lowlevel_ops::rename)(fuse_req_t req, fuse_ino_t parent, const char *name, fuse_ino_t newparent, const char *newname)

Rename a file

If the target exists it should be atomically replaced. If the target's inode's lookup count is non-zero, the file system is expected to postpone any removal of the inode until the lookup count reaches zero (see description of the forget function).

Valid replies: fuse_reply_err

Parameters
reqrequest handle
parentinode number of the old parent directory
nameold name
newparentinode number of the new parent directory
newnamenew name
void(* fuse_lowlevel_ops::retrieve_reply)(fuse_req_t req, void *cookie, fuse_ino_t ino, off_t offset, struct fuse_bufvec *bufv)

Callback function for the retrieve request

Introduced in version 2.9

Valid replies: fuse_reply_none

Parameters
reqrequest handle
cookieuser data supplied to fuse_lowlevel_notify_retrieve()
inothe inode number supplied to fuse_lowlevel_notify_retrieve()
offsetthe offset supplied to fuse_lowlevel_notify_retrieve()
bufvthe buffer containing the returned data
void(* fuse_lowlevel_ops::rmdir)(fuse_req_t req, fuse_ino_t parent, const char *name)

Remove a directory

If the directory's inode's lookup count is non-zero, the file system is expected to postpone any removal of the inode until the lookup count reaches zero (see description of the forget function).

Valid replies: fuse_reply_err

Parameters
reqrequest handle
parentinode number of the parent directory
nameto remove
void(* fuse_lowlevel_ops::setattr)(fuse_req_t req, fuse_ino_t ino, struct stat *attr, int to_set, struct fuse_file_info *fi)

Set file attributes

In the 'attr' argument only members indicated by the 'to_set' bitmask contain valid values. Other members contain undefined values.

If the setattr was invoked from the ftruncate() system call under Linux kernel versions 2.6.15 or later, the fi->fh will contain the value set by the open method or will be undefined if the open method didn't set any value. Otherwise (not ftruncate call, or kernel version earlier than 2.6.15) the fi parameter will be NULL.

Valid replies: fuse_reply_attr fuse_reply_err

Parameters
reqrequest handle
inothe inode number
attrthe attributes
to_setbit mask of attributes which should be set
fifile information, or NULL

Changed in version 2.5: file information filled in for ftruncate

void(* fuse_lowlevel_ops::setlk)(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi, struct flock *lock, int sleep)

Acquire, modify or release a POSIX file lock

For POSIX threads (NPTL) there's a 1-1 relation between pid and owner, but otherwise this is not always the case. For checking lock ownership, 'fi->owner' must be used. The l_pid field in 'struct flock' should only be used to fill in this field in getlk().

Note: if the locking methods are not implemented, the kernel will still allow file locking to work locally. Hence these are only interesting for network filesystems and similar.

Introduced in version 2.6

Valid replies: fuse_reply_err

Parameters
reqrequest handle
inothe inode number
fifile information
lockthe region/type to set
sleeplocking operation may sleep
void(* fuse_lowlevel_ops::setxattr)(fuse_req_t req, fuse_ino_t ino, const char *name, const char *value, size_t size, int flags)

Set an extended attribute

Valid replies: fuse_reply_err

void(* fuse_lowlevel_ops::statfs)(fuse_req_t req, fuse_ino_t ino)

Get file system statistics

Valid replies: fuse_reply_statfs fuse_reply_err

Parameters
reqrequest handle
inothe inode number, zero means "undefined"
void(* fuse_lowlevel_ops::symlink)(fuse_req_t req, const char *link, fuse_ino_t parent, const char *name)

Create a symbolic link

Valid replies: fuse_reply_entry fuse_reply_err

Parameters
reqrequest handle
linkthe contents of the symbolic link
parentinode number of the parent directory
nameto create
void(* fuse_lowlevel_ops::unlink)(fuse_req_t req, fuse_ino_t parent, const char *name)

Remove a file

If the file's inode's lookup count is non-zero, the file system is expected to postpone any removal of the inode until the lookup count reaches zero (see description of the forget function).

Valid replies: fuse_reply_err

Parameters
reqrequest handle
parentinode number of the parent directory
nameto remove
void(* fuse_lowlevel_ops::write)(fuse_req_t req, fuse_ino_t ino, const char *buf, size_t size, off_t off, struct fuse_file_info *fi)

Write data

Write should return exactly the number of bytes requested except on error. An exception to this is when the file has been opened in 'direct_io' mode, in which case the return value of the write system call will reflect the return value of this operation.

fi->fh will contain the value set by the open method, or will be undefined if the open method didn't set any value.

Valid replies: fuse_reply_write fuse_reply_err

Parameters
reqrequest handle
inothe inode number
bufdata to write
sizenumber of bytes to write
offoffset to write to
fifile information
void(* fuse_lowlevel_ops::write_buf)(fuse_req_t req, fuse_ino_t ino, struct fuse_bufvec *bufv, off_t off, struct fuse_file_info *fi)

Write data made available in a buffer

This is a more generic version of the ->write() method. If FUSE_CAP_SPLICE_READ is set in fuse_conn_info.want and the kernel supports splicing from the fuse device, then the data will be made available in pipe for supporting zero copy data transfer.

Introduced in version 2.9

Valid replies: fuse_reply_write fuse_reply_err

Parameters
reqrequest handle
inothe inode number
bufvbuffer containing the data
offoffset to write to
fifile information

The documentation for this struct was generated from the following file: