SETGID(3)                  POSIX Programmer's Manual                 SETGID(3)



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NNAAMMEE
       setgid -- set-group-ID

SSYYNNOOPPSSIISS
       #include <unistd.h>

       int setgid(gid_t _g_i_d);

DDEESSCCRRIIPPTTIIOONN
       If the process has appropriate privileges, _s_e_t_g_i_d() shall set the real
       group ID, effective group ID, and the saved set-group-ID of the calling
       process to _g_i_d.

       If the process does not have appropriate privileges, but _g_i_d is equal
       to the real group ID or the saved set-group-ID, _s_e_t_g_i_d() shall set the
       effective group ID to _g_i_d; the real group ID and saved set-group-ID
       shall remain unchanged.

       The _s_e_t_g_i_d() function shall not affect the supplementary group list in
       any way.

       Any supplementary group IDs of the calling process shall remain
       unchanged.

RREETTUURRNN VVAALLUUEE
       Upon successful completion, 0 is returned. Otherwise, -1 shall be
       returned and _e_r_r_n_o set to indicate the error.

EERRRROORRSS
       The _s_e_t_g_i_d() function shall fail if:

       EEIINNVVAALL The value of the _g_i_d argument is invalid and is not supported by
              the implementation.

       EEPPEERRMM  The process does not have appropriate privileges and _g_i_d does
              not match the real group ID or the saved set-group-ID.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

EEXXAAMMPPLLEESS
       None.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       None.

RRAATTIIOONNAALLEE
       Refer to the RATIONALE section in _s_e_t_u_i_d().

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _e_x_e_c, _g_e_t_e_g_i_d(), _g_e_t_e_u_i_d(), _g_e_t_g_i_d(), _g_e_t_u_i_d(), _s_e_t_e_g_i_d(), _s_e_t_e_u_i_d(),
       _s_e_t_r_e_g_i_d(), _s_e_t_r_e_u_i_d(), _s_e_t_u_i_d()

       The Base Definitions volume of POSIX.1-2017, <<ssyyss__ttyyppeess..hh>>, <<uunniissttdd..hh>>

CCOOPPYYRRIIGGHHTT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  In the event of any discrepancy between this version and the
       original IEEE and The Open Group Standard, the original IEEE and The
       Open Group Standard is the referee document. The original Standard can
       be obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017                            SETGID(3)
