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.\"     @(#)setregid.2	6.4 (Berkeley) 3/10/91
.\"
.\" Modified Sat Jul 24 09:08:49 1993 by Rik Faith (faith@cs.unc.edu)
.\" Portions extracted from linux/kernel/sys.c:
.\"             Copyright (C) 1991, 1992  Linus Torvalds
.\"             May be distributed under the GNU General Public License
.\" Changes: Fri Jul 29 10:56:01 BST 1994 by Wilf. <G.Wilford@ee.surrey.ac.uk>
.\"          Tue Aug  2 14:56:48 BST 1994 by Wilf due to changes in kernel.
.\" Translated into Spanish Mon Jan 26 1998 by
.\"	Gerardo Aburruzaga García <gerardo.aburruzaga@uca.es>
.\"
.TH SETREGID 2 "26 enero 1998" "Linux 1.1.38" "Manual del Programador de Linux"
.SH NOMBRE
setregid, setegid \- establecen el GID efectivo o real
.SH SINOPSIS
.B #include <unistd.h>
.sp
.BI "int setregid(gid_t " rgid ", gid_t " egid );
.br
.BI "int setegid(gid_t " egid );
.SH DESCRIPCIÓN
.B setregid
establece los GIDs real y efectivo del proceso en curso.
Los usuarios no privilegiados pueden cambiar el GID real al GID
efectivo y viceversa.

Antes de Linux 1.1.38, lo del ID salvado, cuando se usaba con
.B setregid 
o
.B setegid
no funcionaba.
A partir del 1.1.38, es posible también establecer el GID efectivo a
partir del GID salvado.

Sólo el súper-usuario puede hacer otros cambios.

Un valor de \-1 para el GID efectivo o para el real, fuerza al sistema
a dejar ese ID intacto.

Actualmente (libc-4.x.x),
.BI setegid( egid )       
es funcionalmente equivalente a
.BI setregid(  -1  , " egid" ).

Si el GID real se cambia o el GID efectivo se pone a un valor distinto
del GID real anterior, el GID salvado tomará el valor del nuevo GID
efectivo. 
.SH "VALOR DEVUELTO"
En caso de éxito se devuelve cero. En caso de error, se devuelve \-1 y
se pone en
.I errno
un valor adecuado.
.SH ERRORES
.TP
.B EPERM
El proceso en curso no es del súper-usuario y se ha especificado un
cambio distinto a

(i) cambiar el GID efectivo con el real, o

(ii) poner uno al valor del otro, o

(iii) poner el GID efectivo al valor del GID salvado.


.SH "CONFORME A"
BSD 4.3 (la función
.B setregid
apareció por primera vez en 4.2BSD).
.SH "VÉASE TAMBIÉN"
.BR getgid (2),
.BR setgid (2)