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GETFH(2) FreeBSD System Calls Manual GETFH(2)
NAME
getfh, lgetfh, getfhat - get file handle
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#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);
DESCRIPTION
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.
RETURN VALUES
[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.
SEE ALSO
fhopen(2), open(2), stat(2)
HISTORY
The getfh() system call first appeared in 4.4BSD. The lgetfh() system
call first appeared in FreeBSD 5.3. The getfhat() system call first
appeared in FreeBSD 12.1.
FreeBSD 14.0-RELEASE-p11 November 30, 2022 FreeBSD 14.0-RELEASE-p11