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 filesystem.
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 " newpath 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 additional 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.