link(2) SYSTEM CALLS link(2)
NAME
link - link to a file
SYNOPSIS
#include <unistd.h>
int link(const char *path1, const char *path2);
DESCRIPTION
path1 points to a path name naming an existing file. path2
points to a path name naming the new directory entry to be
created. link creates a new link (directory entry) for the
existing file and increments its link count by one.
Upon successful completion, link marks for update the
st_ctime field of the file. Also, the st_ctime and st_mtime
fields of the directory that contains the new entry are
marked for update.
link will fail and no link will be created if one or more of
the following are true:
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.
EEXIST The link named by path2 exists.
EFAULT path points outside the allocated
address space of the process.
EINTR A signal was caught during the link sys-
tem call.
ELOOP Too many symbolic links were encountered
in translating path.
EMLINK The maximum number of links to a file
would be exceeded.
EMULTIHOP Components of path require hopping to
multiple remote machines and file system
type does not allow it.
ENAMETOOLONG The length of the path1 or path2 argu-
ment exceeds {PATH_MAX}, or the length
of a path1 or path2 component exceeds
{NAME_MAX} while _POSIX_NO_TRUNC is in
effect.
1
link(2) SYSTEM CALLS link(2)
ENOTDIR A component of either path prefix is not
a directory.
ENOENT path1 or path2 is a null path name.
ENOENT A component of either path prefix does
not exist.
ENOENT The file named by path1 does not exist.
ENOLINK path points to a remote machine and the
link to that machine is no longer
active.
ENOSPC the directory that would contain the
link cannot be extended.
EPERM The file named by path1 is a directory
and the effective user ID is not super-
user.
EROFS The requested link requires writing in a
directory on a read-only file system.
EXDEV The link named by path2 and the file
named by path1 are on different logical
devices (file systems).
SEE ALSO
unlink(2).
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Oth-
erwise, a value of -1 is returned and errno is set to indi-
cate the error.
2