Name
getgrent, setgrent, endgrent — get group file
entry
Synopsis
struct group *getgrent( |
void); |
|
DESCRIPTION
The getgrent() function
returns a pointer to a structure containing the broken-out
fields of a record in the group database (e.g., the local
group file /etc/group, NIS, and
LDAP). The first time it is called it returns the first
entry; thereafter, it returns successive entries.
The setgrent() function
rewinds to the beginning of the group database, to allow
repeated scans.
The endgrent() function is
used to close the group database after all processing has
been performed.
The group
structure is defined in <grp.h> as follows:
| struct |
group { |
| |
char |
* |
gr_name; |
/* group name */ |
| |
char |
* |
gr_passwd; |
/* group password */ |
| |
gid_t |
|
gr_gid; |
/* group ID */ |
| |
char |
** |
gr_mem; |
/* group members */ |
| }; |
RETURN VALUE
The getgrent() function
returns a pointer to a group structure, or NULL if
there are no more entries or an error occurs.
Upon error, errno may be set.
If one wants to check errno
after the call, it should be set to zero before the call.
ERRORS
- EINTR
-
A signal was caught.
- EIO
-
I/O error.
- EMFILE
-
The calling process already has too many open
files.
- ENFILE
-
Too many open files in the system.
- ENOMEM
-
Insufficient memory to allocate group information
structure.
- ERANGE
-
Insufficient buffer space supplied.
FILES
/etc/group-
local group database file
CONFORMING TO
SVr4, 4.3BSD, POSIX.1-2001.
SEE ALSO
fgetgrent(3), getgrent_r(3), getgrgid(3), getgrnam(3), putgrent(3)
Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
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entire resulting derived work is distributed under the terms of a
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Since the Linux kernel and libraries are constantly changing, this
manual page may be incorrect or out-of-date. The author(s) assume no
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the use of the information contained herein. The author(s) may not
have taken the same level of care in the production of this manual,
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Formatted or processed versions of this manual, if unaccompanied by
the source, must acknowledge the copyright and authors of this work.
References consulted:
Linux libc source code
Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
386BSD man pages
Modified Sat Jul 24 19:29:54 1993 by Rik Faith (faith@cs.unc.edu)
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