Computer Science
LINK(2) Linux Programmer's Manual LINK(2)
NAME
link - make a new name for a file
SYNOPSIS
#include <unistd.h>
int link(const char *oldpath, const char *newpath);
DESCRIPTION
link creates a new link (also known as a hard link) to an
existing file.
If newpath exists it will not be overwritten.
This new name may be used exactly as the old one for any
operation; both names refer to the same file (and so have
the same permissions and ownership) and it is impossible
to tell which name was the `original'.
RETURN VALUE
On success, zero is returned. On error, -1 is returned,
and errno is set appropriately.
ERRORS
EXDEV oldpath and newpath are not on the same filesys-
tem.
EPERM The filesystem containing oldpath and newpath does
not support the creation of hard links.
EFAULT oldpath or newpath points outside your accessible
address space.
EACCES Write access to the directory containing newpath
is not allowed for the process's effective uid, or
one of the directories in oldpath or newpath did
not allow search (execute) permission.
ENAMETOOLONG
oldpath or newpath was too long.
ENOENT A directory component in oldpath or newpath does
not exist or is a dangling symbolic link.
ENOTDIR A component used as a directory in oldpath or new-
path is not, in fact, a directory.
ENOMEM Insufficient kernel memory was available.
EROFS The file is on a read-only filesystem.
EEXIST newpath already exists.
EMLINK The file referred to by oldpath already has the
maximum number of links to it.
ELOOP Too many symbolic links were encountered in
resolving oldpath or newpath.
ENOSPC The device containing the file has no room for the
new directory entry.
EPERM oldpath is a directory.
EIO An I/O error occurred.
NOTES
Hard links, as created by link, cannot span filesystems.
Use symlink if this is required.
CONFORMING TO
SVr4, SVID, POSIX, BSD 4.3, X/OPEN. SVr4 documents addi-
tional ENOLINK and EMULTIHOP error conditions; POSIX.1
does not document ELOOP. X/OPEN does not document EFAULT,
ENOMEM or EIO.
BUGS
On NFS file systems, the return code may be wrong in case
the NFS server performs the link creation and dies before
it can say so. Use stat(2) to find out if the link got
created.
SEE ALSO
symlink(2), unlink(2), rename(2), open(2), stat(2), ln(1)
Linux 2.0.30 10 December 1997 1
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