getfh
, lgetfh
,
getfhat
—
get file handle
Standard C Library (libc, -lc)
#include <sys/param.h>
#include <sys/mount.h>
int
getfh
(const
char *path, fhandle_t
*fhp);
int
lgetfh
(const
char *path, fhandle_t
*fhp);
int
getfhat
(int
fd, const char
*path, fhandle_t
*fhp, int
flag);
The getfh
() system call returns a file handle for the
specified file or directory in the file handle pointed to by
fhp.
The lgetfh
() system call is like
getfh
() except in the case where the named file is a
symbolic link, in which case lgetfh
() returns
information about the link, while getfh
() returns
information about the file the link references.
The getfhat
() system call is equivalent to
getfh
() and lgetfh
() except
when the path specifies a relative path. For
getfhat
() and relative path,
the status is retrieved from a file relative to the directory associated
with the file descriptor fd instead of the current
working directory.
The values for the flag are constructed by a
bitwise-inclusive OR of flags from this list, defined in
<fcntl.h>
:
AT_SYMLINK_NOFOLLOW
- If path names a symbolic link, the status of the
symbolic link is returned.
AT_RESOLVE_BENEATH
- Only walk paths below the directory specified by the
fd descriptor. See the description of the
O_RESOLVE_BENEATH
flag in the
open(2)
manual page.
If getfhat
() is passed the special value
AT_FDCWD
in the fd parameter,
the current working directory is used and the behavior is identical to a
call to getfth
() or lgetfh
()
respectively, depending on whether or not the
AT_SYMLINK_NOFOLLOW
bit is set in
flag.
When getfhat
() is called with an absolute
path, it ignores the fd
argument.
These system calls are restricted to the superuser.
Upon successful completion, the value 0 is returned; otherwise the
value -1 is returned and the global variable
errno is set to indicate the error.
The getfh
() and lgetfh
() system
calls fail if one or more of the following are true:
- [
EPERM
]
- The caller does not have appropriate privilege to perform the
operation.
- [
ENOTDIR
]
- A component of the path prefix of path is not a
directory.
- [
ENAMETOOLONG
]
- The length of a component of path exceeds 255
characters, or the length of path exceeds 1023
characters.
- [
ENOENT
]
- The file referred to by path does not exist.
- [
EACCES
]
- Search permission is denied for a component of the path prefix of
path.
- [
ELOOP
]
- Too many symbolic links were encountered in translating
path.
- [
EFAULT
]
- The fhp argument points to an invalid address.
- [
EFAULT
]
- The path argument points to an invalid address.
- [
EIO
]
- An I/O error occurred while reading from or writing to the file
system.
- [
EINTEGRITY
]
- Corrupted data was detected while reading from the file system.
- [
ESTALE
]
- The file handle fhp is no longer valid.
In addition to the errors returned by
getfh
(), and lgetfh
(), the
getfhat
() system call may fail if:
- [
EBADF
]
- The path argument does not specify an absolute path
and the fd argument, is neither
AT_FDCWD
nor a valid file descriptor open for
searching.
- [
EINVAL
]
- The value of the flag argument is not valid.
- [
ENOTDIR
]
- The path argument is not an absolute path and
fd is neither
AT_FDCWD
nor a
file descriptor associated with a directory.
The getfh
() system call first appeared in
4.4BSD.