link(2) link(2) NAME link, linkfollow - link to a file C SYNOPSIS #include <unistd.h> int link (const char *path1, const char *path2); int linkfollow (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. linkfollow is identical to link unless path1 refers to a symbolic link. If path1 is a symbolic link, link will make a link to the symbolic link; linkfollow will make a link to the object that the symbolic link refers to, and will fail if the symbolic link does not refer to any object. link will fail and no link will be created if one or more of the following are true: EACCES Search permission is denied on a component of one of the path prefixes. EACCES Write permission is denied on the directory in which the link is to be created. EACCES Write permission is denied on the file named by path1. EEXIST The link named by path2 exists. EFAULT path1 or path2 points outside the allocated address space of the process. EINTR A signal was caught during the link system call. ELOOP Too many symbolic links were encountered in translating path1 or path2. EMLINK The maximum number of links to a file would be exceeded. EMULTIHOP Components of path1 or path2 require hopping to multiple remote machines and file system type does not allow it. ETIMEDOUT A component of path1 or path2 is located on a remote file system which is not available [see intro(2)]. ENAMETOOLONG The length of the path1 or path2 argument exceeds {PATH_MAX}, or the length of a path1 or path2 component exceeds {NAME_MAX} while _POSIX_NO_TRUNC is in effect. 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 ENOLINK path1 or path2 points to a remote machine and the link to that machine is no longer active.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. 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 symlink(2), unlink(2), realpath(3). DIAGNOSTICS Upon successful completion, a value of 0 is returned. Otherwise, a value of -1 is returned and errno is set to indicate the error. Page 2