setreuid(2) [osf1 man page]

setreuid(2)							System Calls Manual						       setreuid(2)

NAME

       setreuid - Sets real and effective user IDs

SYNOPSIS

       #include <unistd.h> setreuid(	  uid_t ruid,	   uid_t euid );

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       setreuid:  XPG4-UNIX

       Refer to the standards(5) reference page for more information about industry standards and associated tags.

PARAMETERS

       Specifies the new real user ID.	Specifies the new effective user ID.

DESCRIPTION

       The  setreuid()	function  sets the real and effective user IDs of the current process to the values specified by the ruid and euid parame-
       ters.  If ruid or euid is -1, the corresponding effective or real user ID of the current process is not changed.

       Users may change the effective user ID to the real user ID; only processes with superuser privilege may make other changes.  This  task	is
       normally done by the system's authentication program (for example, login), but is not done for system daemons.

RETURN VALUES

       Upon successful completion, a value of 0 (zero) is returned.  Otherwise, a value of -1 is returned and errno is set to indicate the error.

ERRORS

       The setreuid() function sets errno to the specified values for the following conditions: The value of the ruid or euid parameter is invalid
       or out of range.  The current process is not the superuser and a change other than changing the effective user ID to the real user  ID  was
       specified.

RELATED INFORMATION

       Functions: getuid(2), setgid(2), setregid(2), setruid(3)

       Standards: standards(5) delim off

																       setreuid(2)

setreuid(2)							System Calls Manual						       setreuid(2)

Name
       setreuid - set real and effective user ID's

Syntax
       setreuid(ruid, euid)
       intruid, euid;

Description
       The  real  and  effective  user	ID's 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.

Return Values
       Upon successful completion, a value of zero (0) is returned.  Otherwise, a value of -1 is returned and errno is set to indicate the error.

Environment
       BSD
       If the process is superuser, or and matches with the real user ID, the effective user ID, or the saved set-user-id (as described in ), then
       the real, effective, and the saved set-user-id are set to and respectively.

       POSIX
       SYSTEM-FIVE
       When  your  program  is	compiled  in the POSIX or SYSTEM-FIVE mode, if both arguments to are -1, the system call returns a value of -1 and
       errno is set to [EINVAL].

       The following semantics apply when using the function:

       If the process is the superuser, the real, effective, and saved set-user-id (as described in ) are set to and respectively.

       If the process is not the superuser, but the and matches with the real user ID, the effective user ID (only  in	the  SYSTEM-FIVE  and  BSD
       environments), or the saved set-user-id, then the effective ID is set to The  real user ID and the saved set-user-id are left unchanged.

Diagnostics
       [EPERM]	      The  current  process is not the superuser and the and specified does not match with the real user ID, the effective user ID
		      (only in SYSTEM-FIVE and BSD environment), or the saved set-user-id.

See Also
       getuid(2), setregid(2), setuid(3)

																       setreuid(2)