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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 pathname exceeds {PATH_MAX} or a pathname compo-
              nent 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 of path is not a directory.
       EOPNOTSUPP
              The path argument names a symbolic link and  the  implementation
              does not support setting the owner or group of a symbolic link.
       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
              Pathname resolution of a symbolic link produced an  intermediate
              result whose length 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
       IEEE Std 1003.1-2001, <unistd.h>
COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
       Electrical  and  Electronics  Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                           LCHOWN(3P)