initgroups

INITGROUPS(3)              Linux Programmer's Manual             INITGROUPS(3)



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 appropriately.

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 5.07 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/.



GNU                               2017-09-15                     INITGROUPS(3)