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 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.

       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.


SEE ALSO

       symlink(2), unlink(2), rename(2), open(2), stat(2), ln(1)

Linux 2.0.30                      1997-12-10                           link(2)