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SYMLINK(2)                 Linux Programmer's ManualSYMLINK(2)NAME       symlink, symlinkat - make a new name for a fileSYNOPSIS       #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 (seefeature_test_macros(7)):       symlink():           _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200112L               || /* Glibc versions <= 2.19: */ _BSD_SOURCE       symlinkat():           Since glibc 2.10:               _POSIX_C_SOURCE >= 200809L           Before glibc 2.10:               _ATFILE_SOURCEDESCRIPTION       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 directory.       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 ig-       nored  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.   symlinkat()       The  symlinkat()  system  call operates in exactly the same way as sym-       link(), 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.RETURN VALUE       On  success,  zero is returned.  On error, -1 is returned, and errno is       set appropriately.ERRORS       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 alsopath_resolution(7).)       EDQUOT The user's quota of resources on the  filesystem  has  been  ex-              hausted.   The resources could be inodes or disk blocks, depend-              ing 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.       ENAMETOOLONG              target or linkpath was too long.       ENOENT A directory component in linkpath does not exist or  is  a  dan-              gling symbolic link, or target or linkpath is an empty string.       ENOMEM Insufficient kernel memory was available.       ENOSPC The device containing the file has no room for the new directory              entry.       ENOTDIR              A component used as a directory in linkpath is not, in  fact,  a              directory.       EPERM  The filesystem containing linkpath does not support the creation              of symbolic links.       EROFS  linkpath is on a read-only filesystem.       The following additional errors can occur for symlinkat():       EBADF  newdirfd is not a valid file descriptor.       ENOENT linkpath is a relative pathname and newdirfd refers to a  direc-              tory that has been deleted.       ENOTDIR              linkpath is relative and newdirfd is a file descriptor referring              to a file other than a directory.VERSIONS       symlinkat() was added to Linux in kernel 2.6.16;  library  support  was       added to glibc in version 2.4.CONFORMING TO       symlink(): SVr4, 4.3BSD, POSIX.1-2001, POSIX.1-2008.       symlinkat(): POSIX.1-2008.NOTES       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, uselink(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  rela-       tive  pathname,  glibc constructs a pathname based on the symbolic link       in /proc/self/fd that corresponds to the newdirfd argument.SEE ALSOln(1),namei(1),lchown(2),link(2),lstat(2),open(2),readlink(2),rename(2),unlink(2),path_resolution(7),symlink(7)COLOPHON       This  page  is  part of release 5.05 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       https://www.kernel.org/doc/man-pages/.Linux                             2017-09-15SYMLINK(2)