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28 .\" @(#)setreuid.2 8.2 (Berkeley) 4/16/94
29 .\" $FreeBSD: src/lib/libc/sys/setreuid.2,v 1.6.2.6 2001/12/14 18:34:01 ru Exp $
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37 .Nd set real and effective user ID's
43 .Fn setreuid "uid_t ruid" "uid_t euid"
45 The real and effective user IDs of the
46 current process are set according to the arguments.
51 is -1, the current uid is filled in by the system.
52 Unprivileged users may change the real user
53 ID to the effective user ID and vice-versa; only the super-user may
58 function has been used to swap the real and effective user IDs
59 in set-user-ID programs to temporarily relinquish the set-user-ID value.
60 This purpose is now better served by the use of the
65 When setting the real and effective user IDs to the same value,
68 function is preferred.
74 The current process is not the super-user and a change
75 other than changing the effective user-id to the real user-id
86 system call appeared in