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FCHOWN(3P)                 POSIX Programmer's Manual                FCHOWN(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
       fchown -- change owner and group of a file
SYNOPSIS
       #include <unistd.h>
       int fchown(int fildes, uid_t owner, gid_t group);
DESCRIPTION
       The fchown() function shall be equivalent to chown()  except  that  the
       file  whose  owner  and  group  are  changed  is  specified by the file
       descriptor fildes.
RETURN VALUE
       Upon successful completion, fchown()  shall  return  0.  Otherwise,  it
       shall return -1 and set errno to indicate the error.
ERRORS
       The fchown() function shall fail if:
       EBADF  The fildes argument is not an open file descriptor.
       EPERM  The  effective  user  ID does not match the owner of the file or
              the  process  does   not   have   appropriate   privileges   and
              _POSIX_CHOWN_RESTRICTED   indicates   that   such  privilege  is
              required.
       EROFS  The file referred to by fildes resides on a read-only file  sys-
              tem.
       The fchown() function may fail if:
       EINVAL The  owner or group ID is not a value supported by the implemen-
              tation.  The fildes argument refers to a pipe or  socket  or  an
              fattach()-ed  STREAM  and the implementation disallows execution
              of fchown() on a pipe.
       EIO    A physical I/O error has occurred.
       EINTR  The fchown() function was interrupted  by  a  signal  which  was
              caught.
       The following sections are informative.
EXAMPLES
   Changing the Current Owner of a File
       The  following  example  shows  how to change the owner of a file named
       /home/cnd/mod1 to ``jones'' and the group to ``cnd''.
       The numeric value for the user ID is obtained by extracting the user ID
       from  the user database entry associated with ``jones''. Similarly, the
       numeric value for the group ID is obtained by extracting the  group  ID
       from  the  group  database  entry associated with ``cnd''. This example
       assumes the calling program has appropriate privileges.
           #include <sys/types.h>
           #include <unistd.h>
           #include <fcntl.h>
           #include <pwd.h>
           #include <grp.h>
           struct passwd *pwd;
           struct group  *grp;
           int            fildes;
           ...
           fildes = open("/home/cnd/mod1", O_RDWR);
           pwd = getpwnam("jones");
           grp = getgrnam("cnd");
           fchown(fildes, pwd->pw_uid, grp->gr_gid);
APPLICATION USAGE
       None.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       chown()
       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                           FCHOWN(3P)