NAME

       initgroups - initialize the supplementary group access list

SYNOPSIS

       #include <sys/types.h>
       #include <grp.h>

       int initgroups(const char *user, gid_t group);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       initgroups():
           Since glibc 2.19:
               _DEFAULT_SOURCE
           Glibc 2.19 and earlier:
               _BSD_SOURCE

DESCRIPTION

       The  initgroups() function initializes the group access list by reading the group database
       /etc/group and using all groups of which user is a member.  The additional group group  is
       also added to the list.

       The user argument must be non-NULL.

RETURN VALUE

       The  initgroups()  function  returns 0 on success.  On error, -1 is returned, and errno is
       set to indicate the error.

ERRORS

       ENOMEM Insufficient memory to allocate group information structure.

       EPERM  The calling process has insufficient privilege.  See  the  underlying  system  call
              setgroups(2).

FILES

       /etc/group
              group database file

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌────────────────────────────────────────────────────────┬───────────────┬────────────────┐
       │Interface                                               │ Attribute     │ Value          │
       ├────────────────────────────────────────────────────────┼───────────────┼────────────────┤
       │initgroups()                                            │ Thread safety │ MT-Safe locale │
       └────────────────────────────────────────────────────────┴───────────────┴────────────────┘

CONFORMING TO

       SVr4, 4.3BSD.

SEE ALSO

       getgroups(2), setgroups(2), credentials(7)

COLOPHON

       This  page  is  part of release 5.13 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at https://www.kernel.org/doc/man-pages/.