setreuid(2) [hpux man page]

setreuid(2)							System Calls Manual						       setreuid(2)

NAME

       setreuid - set real and effective user IDs

SYNOPSIS

DESCRIPTION

       The function sets the real and effective user IDs of the current process to the values specified by the ruid and euid arguments. If ruid or
       euid is -1, the corresponding effective or real user ID of the current process is left unchanged.

       A process with appropriate privileges can set either ID to any value. An unprivileged process can only set the effective  user  ID  if  the
       euid argument is equal to either the real, effective, or saved user ID of the process.

       It  is  unspecified  whether  a	process  without appropriate privileges is permitted to change the real user ID to match the current real,
       effective or saved user ID of the process.

RETURN VALUE

       Upon successful completion, 0 is returned. Otherwise, -1 is returned and is set to indicate the error.

ERRORS

       The function will fail if:

	      [EINVAL]		       The value of the ruid or euid argument is invalid or out-of-range.

	      [EPERM]		       The current process does not have appropriate privileges, and either an attempt	was  made  to  change  the
				       effective user ID to a value other than the real user ID or the saved set-user-ID or an attempt was made to
				       change the real user ID to a value not permitted by the implementation.

SEE ALSO

       getuid(2), setuid(2), <unistd.h>.

CHANGE HISTORY

       First released in Issue 4, Version 2.

																       setreuid(2)

SETREUID(2)						      BSD System Calls Manual						       SETREUID(2)

NAME

     setreuid -- set real and effective user ID's

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <unistd.h>

     int
     setreuid(uid_t ruid, uid_t euid);

DESCRIPTION

     The real and effective user IDs of the current process are set according to the arguments.  If ruid or euid is -1, the current uid is filled
     in by the system.	Unprivileged users may change the real user ID to the effective user ID and vice-versa; only the super-user may make other
     changes.

     If the real user ID is changed (i.e. ruid is not -1) or the effective user ID is changed to something other than the real user ID, then the
     saved user ID will be set to the effective user ID.

     The setreuid() system call has been used to swap the real and effective user IDs in set-user-ID programs to temporarily relinquish the set-
     user-ID value.  This purpose is now better served by the use of the seteuid(2) system call.

     When setting the real and effective user IDs to the same value, the standard setuid() system call is preferred.

RETURN VALUES

     The setreuid() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indi-
     cate the error.

ERRORS

     [EPERM]		The current process is not the super-user and a change other than changing the effective user-id to the real user-id was
			specified.

SEE ALSO

     getuid(2), issetugid(2), seteuid(2), setuid(2)

HISTORY

     The setreuid() system call appeared in 4.2BSD.

BSD
								 February 8, 2001							       BSD