.\"	$NetBSD: do_setresuid.9,v 1.6 2017/05/19 14:35:01 abhinav Exp $
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.\" by David Laight.
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.Dd September 28, 2003
.Dt DO_SETRESUID 9
.Os
.Sh NAME
.Nm do_setresuid ,
.Nm do_setresgid
.Nd set process uid and gid
.Sh SYNOPSIS
.In sys/ucred.h
.Ft int
.Fn do_setresuid "struct lwp *lwp" "uid_t ruid" "uid_t euid" "uid_t svuid" "u_int flags"
.Ft int
.Fn do_setresgid "struct lwp *lwp" "uid_t ruid" "uid_t euid" "uid_t svuid" "u_int flags"
.Sh DESCRIPTION
The
.Nm do_setresuid
and
.Nm do_setresgid
functions are used to implement the various system calls that allow a
process to change its real, effective, and saved uid and gid values.
.Pp
The
.Nm do_setresuid
function sets the specified processes real user ID to
.Ar ruid ,
its effective user ID to
.Ar euid ,
and its saved user ID to
.Ar svuid .
If any of the uid arguments are \-1 then that assignment is skipped.
.Pp
If
.Fn suser
is true, then any values may be assigned, otherwise the new uid
values must match one of the existing values and the caller must have
set the relevant bit in
.Ar flags .
.Pp
The
.Ar flags
argument specifies which of the existing uid values the new value must match.
It should be set to a logical OR of ID_{R,E,S}_EQ_{R,E,S}, where ID_E_EQ_R
means that it is valid to set the effective ID to the current value of the
real ID.
.Pp
The
.Nm do_setresgid
function sets the group IDs but otherwise behaves in the same manner as
.Nm .
The processes group list is neither examined nor effected.
.Sh CODE REFERENCES
These functions are implemented in:
.Pa sys/kern/kern_prot.c .
.Sh SEE ALSO
.Xr setregid 2 ,
.Xr setreuid 2 ,
.Xr setuid 2
.Sh HISTORY
Implemented for
.Nx 2.0
to replace ad-hoc code in each system call routine and in the
various compat modules.