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LCHOWN(3P)                 POSIX Programmer's Manual                LCHOWN(3P)
PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
NAME
       lchown -- change the owner and group of a symbolic link
SYNOPSIS
       #include <unistd.h>
       int lchown(const char *path, uid_t owner, gid_t group);
DESCRIPTION
       The lchown() function shall be equivalent to  chown(),  except  in  the
       case  where  the  named file is a symbolic link. In this case, lchown()
       shall change the ownership of the  symbolic  link  file  itself,  while
       chown()  changes  the  ownership  of the file or directory to which the
       symbolic link refers.
RETURN VALUE
       Upon successful completion, lchown()  shall  return  0.  Otherwise,  it
       shall return -1 and set errno to indicate an error.
ERRORS
       The lchown() function shall fail if:
       EACCES Search permission is denied on a component of the path prefix of
              path.
       EINVAL The owner or group ID is not a value supported by the  implemen-
              tation.
       ELOOP  A loop exists in symbolic links encountered during resolution of
              the path argument.
       ENAMETOOLONG
              The  length  of  a  component  of  a  pathname  is  longer  than
              {NAME_MAX}.
       ENOENT A component of path does not name an existing file or path is an
              empty string.
       ENOTDIR
              A component of the path prefix names an existing  file  that  is
              neither  a  directory nor a symbolic link to a directory, or the
              path argument contains at least one  non-<slash>  character  and
              ends  with  one or more trailing <slash> characters and the last
              pathname component names an existing  file  that  is  neither  a
              directory nor a symbolic link to a directory.
       EPERM  The  effective  user ID does not match the owner of the file and
              the process does not have appropriate privileges.
       EROFS  The file resides on a read-only file system.
       The lchown() function may fail if:
       EIO    An I/O error occurred while reading or writing to the file  sys-
              tem.
       EINTR  A signal was caught during execution of the function.
       ELOOP  More  than  {SYMLOOP_MAX} symbolic links were encountered during
              resolution of the path argument.
       ENAMETOOLONG
              The length of a pathname exceeds {PATH_MAX}, or pathname resolu-
              tion  of  a symbolic link produced an intermediate result with a
              length that exceeds {PATH_MAX}.
       The following sections are informative.
EXAMPLES
   Changing the Current Owner of a File
       The following example shows how to change the ownership of the symbolic
       link  named /modules/pass1 to the user ID associated with ``jones'' and
       the group ID associated with ``cnd''.
       The numeric value for the user ID is obtained by using  the  getpwnam()
       function.  The  numeric value for the group ID is obtained by using the
       getgrnam() function.
           #include <sys/types.h>
           #include <unistd.h>
           #include <pwd.h>
           #include <grp.h>
           struct passwd *pwd;
           struct group  *grp;
           char          *path = "/modules/pass1";
           ...
           pwd = getpwnam("jones");
           grp = getgrnam("cnd");
           lchown(path, pwd->pw_uid, grp->gr_gid);
APPLICATION USAGE
       On implementations which support symbolic links  as  directory  entries
       rather than files, lchown() may fail.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       chown(), symlink()
       The Base Definitions volume of POSIX.1-2008, <unistd.h>
COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
       cal  and  Electronics  Engineers,  Inc  and  The  Open Group.  (This is
       POSIX.1-2008 with the 2013 Technical Corrigendum  1  applied.)  In  the
       event of any discrepancy between this version and the original IEEE and
       The Open Group Standard, the original IEEE and The Open Group  Standard
       is  the  referee document. The original Standard can be obtained online
       at http://www.unix.org/online.html .
       Any typographical or formatting errors that appear  in  this  page  are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors,  see  https://www.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                           LCHOWN(3P)