Section (3) initgroups


Linux manual pages Section 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);
 
[Note] Note
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 4.16 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/.


  Copyright 1993 David Metcalfe (davidprism.demon.co.uk)

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References consulted:
    Linux libc source code
    Lewine_zsingle_quotesz_s _POSIX Programmer_zsingle_quotesz_s Guide_ (O_zsingle_quotesz_Reilly & Associates, 1991)
    386BSD man pages
Modified 1993-07-24 by Rik Faith <faithcs.unc.edu>
Modified 2004-10-10 by aeb