SYMLINK(2)                  Linux Programmer's Manual                 SYMLINK(2)

       symlink, symlinkat - make a new name for a file

       #include <unistd.h>

       int symlink(const char *target, const char *linkpath);

       #include <fcntl.h>           /* Definition of AT_* constants */
       #include <unistd.h>

       int symlinkat(const char *target, int newdirfd, const char *linkpath);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

           _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200112L
               || /* Glibc <= 2.19: */ _BSD_SOURCE

           Since glibc 2.10:
               _POSIX_C_SOURCE >= 200809L
           Before glibc 2.10:

       symlink() creates a symbolic link named linkpath which contains the
       string target.

       Symbolic links are interpreted at run time as if the contents of the link
       had been substituted into the path being followed to find a file or

       Symbolic links may contain ..  path components, which (if used at the
       start of the link) refer to the parent directories of that in which the
       link resides.

       A symbolic link (also known as a soft link) may point to an existing file
       or to a nonexistent one; the latter case is known as a dangling link.

       The permissions of a symbolic link are irrelevant; the ownership is
       ignored when following the link, but is checked when removal or renaming
       of the link is requested and the link is in a directory with the sticky
       bit (S_ISVTX) set.

       If linkpath exists, it will not be overwritten.

       The symlinkat() system call operates in exactly the same way as
       symlink(), except for the differences described here.

       If the pathname given in linkpath is relative, then it is interpreted
       relative to the directory referred to by the file descriptor newdirfd
       (rather than relative to the current working directory of the calling
       process, as is done by symlink() for a relative pathname).

       If linkpath is relative and newdirfd is the special value AT_FDCWD, then
       linkpath is interpreted relative to the current working directory of the
       calling process (like symlink()).

       If linkpath is absolute, then newdirfd is ignored.

       See openat(2) for an explanation of the need for symlinkat().

       On success, zero is returned.  On error, -1 is returned, and errno is set
       to indicate the error.

       EACCES Write access to the directory containing linkpath is denied, or
              one of the directories in the path prefix of linkpath did not
              allow search permission.  (See also path_resolution(7).)

       EBADF  (symlinkat()) linkpath is relative but newdirfd is neither
              AT_FDCWD nor a valid file descriptor.

       EDQUOT The user's quota of resources on the filesystem has been
              exhausted.  The resources could be inodes or disk blocks,
              depending on the filesystem implementation.

       EEXIST linkpath already exists.

       EFAULT target or linkpath points outside your accessible address space.

       EIO    An I/O error occurred.

       ELOOP  Too many symbolic links were encountered in resolving linkpath.

              target or linkpath was too long.

       ENOENT A directory component in linkpath does not exist or is a dangling
              symbolic link, or target or linkpath is an empty string.

       ENOENT (symlinkat()) linkpath is a relative pathname and newdirfd refers
              to a directory that has been deleted.

       ENOMEM Insufficient kernel memory was available.

       ENOSPC The device containing the file has no room for the new directory

              A component used as a directory in linkpath is not, in fact, a

              (symlinkat()) linkpath is relative and newdirfd is a file
              descriptor referring to a file other than a directory.

       EPERM  The filesystem containing linkpath does not support the creation
              of symbolic links.

       EROFS  linkpath is on a read-only filesystem.

       symlinkat() was added to Linux in kernel 2.6.16; library support was
       added to glibc in version 2.4.

       symlink(): SVr4, 4.3BSD, POSIX.1-2001, POSIX.1-2008.

       symlinkat(): POSIX.1-2008.

       No checking of target is done.

       Deleting the name referred to by a symbolic link will actually delete the
       file (unless it also has other hard links).  If this behavior is not
       desired, use link(2).

   Glibc notes
       On older kernels where symlinkat() is unavailable, the glibc wrapper
       function falls back to the use of symlink().  When linkpath is a relative
       pathname, glibc constructs a pathname based on the symbolic link in
       /proc/self/fd that corresponds to the newdirfd argument.

       ln(1), namei(1), lchown(2), link(2), lstat(2), open(2), readlink(2),
       rename(2), unlink(2), path_resolution(7), symlink(7)

       This page is part of release 5.13 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at

Linux                              2021-08-27                         SYMLINK(2)