ggeetteeuuiidd() -- System Call (libc)

Get effective user identifier
#iinncclluuddee <uunniissttdd.hh>
ggeetteeuuiidd()

Every process  has two different versions  of its _u_s_e_r _i_d,  called the _r_e_a_l
user id and  the _e_f_f_e_c_t_i_v_e user id.  The user  ids determine eligibility to
access  files or  employ system  privileges.  Normally,  these two  ids are
identical.  However,  for a _s_e_t  _u_s_e_r _i_d load  module (see eexxeecc),  the real
user id is  that of the user, whereas the  effective user id is that of the
load module  owner.  This distinction  allows system programs  to use files
which are protected from the user who invokes the program.

ggeetteeuuiidd() returns the effective user identifier

_E_x_a_m_p_l_e
For an example of this call, see the entry for ggeettppwweenntt().

_S_e_e _A_l_s_o
aacccceessss(),  eexxeecc,  ggeetteeggiidd(),  ggeettggiidd(),  ggeettuuiidd(), lliibbcc,  llooggiinn,  sseettuuiidd(),
uunniissttdd.hh
POSIX Standard, section 4.2.1
