initgroups(3)

1initgroups(3)              Library Functions Manual              initgroups(3)
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NAME

6       initgroups - initialize the supplementary group access list
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LIBRARY

9       Standard C library (libc, -lc)
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SYNOPSIS

12       #include <sys/types.h>
13       #include <grp.h>
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15       int initgroups(const char *user, gid_t group);
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17   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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19       initgroups():
20           Since glibc 2.19:
21               _DEFAULT_SOURCE
22           glibc 2.19 and earlier:
23               _BSD_SOURCE
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DESCRIPTION

26       The  initgroups() function initializes the group access list by reading
27       the group database /etc/group and using all groups of which user  is  a
28       member.  The additional group group is also added to the list.
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30       The user argument must be non-NULL.
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RETURN VALUE

33       The  initgroups()  function  returns 0 on success.  On error, -1 is re‐
34       turned, and errno is set to indicate the error.
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ERRORS

37       ENOMEM Insufficient memory to allocate group information structure.
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39       EPERM  The calling process has insufficient privilege.  See the  under‐
40              lying system call setgroups(2).
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FILES

43       /etc/group
44              group database file
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ATTRIBUTES

47       For  an  explanation  of  the  terms  used  in  this  section,  see at‐
48       tributes(7).
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50       ┌─────────────────────────────────────┬───────────────┬────────────────┐
51       │Interface                            │ Attribute     │ Value          │
52       ├─────────────────────────────────────┼───────────────┼────────────────┤
53       │initgroups()                         │ Thread safety │ MT-Safe locale │
54       └─────────────────────────────────────┴───────────────┴────────────────┘
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STANDARDS

57       None.
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HISTORY

60       SVr4, 4.3BSD.
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