The
link();
function atomically creates the specified directory entry (hard link)
name2
with the attributes of the underlying object pointed at by
name1.
If the link is successful: the link count of the underlying object
is incremented;
name1
and
name2
share equal access and rights to the underlying object.
If
name1
is removed, the file
name2
is not deleted and the link count of the underlying object is decremented.
name1
must exist for the hard link to succeed and both
name1
and
name2
must be in the same file system.
As mandated by POSIX.1
name1
may not be a directory.
RETURN VALUES
Upon successful completion, a value of 0 is returned.
Otherwise, a value of \-1 is returned and
errno
is set to indicate the error.
ERRORS
link();
will fail and no link will be created if:
[ENOTDIR]
A component of either path prefix is not a directory.
[ENAMETOOLONG]
A component of a pathname exceeded
{NAME_MAX}
characters, or an entire path name exceeded
{PATH_MAX}
characters.
[ENOENT]
A component of either path prefix does not exist.
[EOPNOTSUPP]
The file system containing the file named by
name1
does not support links.
[EMLINK]
The link count of the file named by
name1
would exceed
LINK_MAX.
[EACCES]
A component of either path prefix denies search permission.
[EACCES]
The requested link requires writing in a directory with a mode
that denies write permission.
[ELOOP]
Too many symbolic links were encountered in translating one of the pathnames.
[ENOENT]
The file named by
name1
does not exist.
[EEXIST]
The link named by
name2
does exist.
[EPERM]
The file named by
name1
is a directory and the effective
user ID is not superuser,
or the file system containing the file does not permit the use of
link();
on a directory.
[EPERM]
The file named by
name1
is flagged immutable or append-only.
[EXDEV]
The link named by
name2
and the file named by
name1
are on different file systems.
[ENOSPC]
The directory in which the entry for the new link is being placed
cannot be extended because there is no space left on the file
system containing the directory.
[EDQUOT]
The directory in which the entry for the new link
is being placed cannot be extended because the
user's quota of disk blocks on the file system
containing the directory has been exhausted.
[EIO]
An I/O error occurred while reading from or writing to
the file system to make the directory entry.
[EROFS]
The requested link requires writing in a directory on a read-only file
system.
[EFAULT]
One of the pathnames specified
is outside the process's allocated address space.