.Dt SYMLINK 2
.Os BSD 4.2
.Sh NAME
-.Nm symlink
+.Nm symlink ,
+.Nm symlinkat
.Nd make symbolic link to a file
.Sh SYNOPSIS
.Fd #include <unistd.h>
.Ft int
-.Fn symlink "const char *name1" "const char *name2"
+.Fo symlink
+.Fa "const char *path1"
+.Fa "const char *path2"
+.Fc
+.Ft int
+.Fn symlinkat "const char *name1" "int fd" "const char *name2"
.Sh DESCRIPTION
A symbolic link
-.Fa name2
+.Fa path2
is created to
-.Fa name1
-.Pf ( Fa name2
+.Fa path1
+.Pf ( Fa path2
is the name of the
file created,
-.Fa name1
+.Fa path1
is the string
used in creating the symbolic link).
Either name may be an arbitrary path name; the files need not
be on the same file system.
+.Pp
+The
+.Fn symlinkat
+system call is equivalent to
+.Fn symlink
+except in the case where
+.Fa name2
+specifies a relative path.
+In this case the symbolic link is created relative to the directory
+associated with the file descriptor
+.Fa fd
+instead of the current working directory.
+If
+.Fn symlinkat
+is passed the special value
+.Dv AT_FDCWD
+in the
+.Fa fd
+parameter, the current working directory is used and the behavior is
+identical to a call to
+.Fn symlink .
.Sh RETURN VALUES
Upon successful completion, a zero value is returned.
If an error occurs, the error code is stored in
.Sh ERRORS
The symbolic link succeeds unless:
.Bl -tag -width Er
-.It Bq Er ENOTDIR
-A component of the
-.Fa name2
-prefix is not a directory.
-.It Bq Er ENAMETOOLONG
-A component of a pathname exceeded
-.Dv {NAME_MAX}
-characters, or an entire path name exceeded
-.Dv {PATH_MAX}
-characters.
-.It Bq Er ENOENT
-The named file does not exist.
+.\" ===========
+.It Bq Er EACCES
+Write permission is denied in the directory
+where the symbolic link is being created.
+.\" ===========
.It Bq Er EACCES
A component of the
-.Fa name2
+.Fa path2
path prefix denies search permission.
-.It Bq Er ELOOP
-Too many symbolic links were encountered in translating the pathname.
+.\" ===========
+.It Bq Er EDQUOT
+The directory in which the entry for the new symbolic link
+is being placed cannot be extended because the
+user's quota of disk blocks on the file system
+containing the directory has been exhausted.
+.\" ===========
+.It Bq Er EDQUOT
+The new symbolic link cannot be created because the user's
+quota of disk blocks on the file system that will
+contain the symbolic link has been exhausted.
+.\" ===========
+.It Bq Er EDQUOT
+The user's quota of inodes on the file system on
+which the symbolic link is being created has been exhausted.
+.\" ===========
.It Bq Er EEXIST
-.Fa Name2
+.Fa Path2
already exists.
+.\" ===========
+.It Bq Er EFAULT
+.Fa Path1
+or
+.Fa path2
+points outside the process's allocated address space.
+.\" ===========
+.It Bq Er EIO
+An I/O error occurs while making the directory entry
+or allocating the inode.
+.\" ===========
.It Bq Er EIO
-An I/O error occurred while making the directory entry for
-.Fa name2 ,
+An I/O error occurs while making the directory entry for
+.Fa path2 ,
or allocating the inode for
-.Fa name2 ,
+.Fa path2 ,
or writing out the link contents of
-.Fa name2 .
-.It Bq Er EROFS
-The file
-.Fa name2
-would reside on a read-only file system.
+.Fa path2 .
+.\" ===========
+.It Bq Er ELOOP
+Too many symbolic links are encountered in translating the pathname.
+This is taken to be indicative of a looping symbolic link.
+.\" ===========
+.It Bq Er ENAMETOOLONG
+A component of a pathname exceeds
+.Dv {NAME_MAX}
+characters, or an entire path name exceeds
+.Dv {PATH_MAX}
+characters.
+.\" ===========
+.It Bq Er ENOENT
+A component of
+.Fa path2
+does not name an existing file or
+.Fa path2
+is an empty string.
+.\" ===========
.It Bq Er ENOSPC
The directory in which the entry for the new symbolic link is being placed
cannot be extended because there is no space left on the file
system containing the directory.
+.\" ===========
.It Bq Er ENOSPC
The new symbolic link cannot be created because there
there is no space left on the file
system that will contain the symbolic link.
+.\" ===========
.It Bq Er ENOSPC
There are no free inodes on the file system on which the
symbolic link is being created.
-.It Bq Er EDQUOT
-The directory in which the entry for the new symbolic link
-is being placed cannot be extended because the
-user's quota of disk blocks on the file system
-containing the directory has been exhausted.
-.It Bq Er EDQUOT
-The new symbolic link cannot be created because the user's
-quota of disk blocks on the file system that will
-contain the symbolic link has been exhausted.
-.It Bq Er EDQUOT
-The user's quota of inodes on the file system on
-which the symbolic link is being created has been exhausted.
-.It Bq Er EIO
-An I/O error occurred while making the directory entry or allocating the inode.
-.It Bq Er EFAULT
-.Fa Name1
-or
+.\" ===========
+.It Bq Er ENOTDIR
+A component of the
+.Fa path2
+prefix is not a directory.
+.\" ===========
+.It Bq Er EROFS
+The file
+.Fa path2
+would reside on a read-only file system.
+.El
+.Pp
+In addition to the errors returned by the
+.Fn symlink ,
+the
+.Fn symlinkat
+may fail if:
+.Bl -tag -width Er
+.It Bq Er EBADF
+The
.Fa name2
-points outside the process's allocated address space.
+argument does not specify an absolute path and the
+.Fa fd
+argument is neither
+.Dv AT_FDCWD
+nor a valid file descriptor open for searching.
+.It Bq Er ENOTDIR
+The
+.Fa name2
+argument is not an absolute path and
+.Fa fd
+is neither
+.Dv AT_FDCWD
+nor a file descriptor associated with a directory.
.El
.Sh SEE ALSO
.Xr ln 1 ,
.Xr link 2 ,
-.Xr unlink 2
-.Xr symlink 7 ,
+.Xr unlink 2 ,
+.Xr symlink 7
+.Sh STANDARDS
+The
+.Fn symlinkat
+system call is expected to conform to POSIX.1-2008 .
.Sh HISTORY
The
.Fn symlink
function call appeared in
.Bx 4.2 .
+The
+.Fn symlinkat
+system call appeared in OS X 10.10
projects / apple / xnu.git / blobdiff