+++ /dev/null
-.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" 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,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" References consulted:
-.\" Linux libc source code
-.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
-.\" 386BSD man pages
-.\"
-.\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu)
-.\" Modified 2003-11-15 by aeb
-.\"
-.TH GETGRNAM 3 2014-08-19 "" "Linux Programmer's Manual"
-.SH NAME
-getgrnam, getgrnam_r, getgrgid, getgrgid_r \- get group file entry
-.SH SYNOPSIS
-.nf
-.B #include <sys/types.h>
-.B #include <grp.h>
-.sp
-.BI "struct group *getgrnam(const char *" name );
-.sp
-.BI "struct group *getgrgid(gid_t " gid );
-.sp
-.BI "int getgrnam_r(const char *" name ", struct group *" grp ,
-.br
-.BI " char *" buf ", size_t " buflen ", struct group **" result );
-.sp
-.BI "int getgrgid_r(gid_t " gid ", struct group *" grp ,
-.br
-.BI " char *" buf ", size_t " buflen ", struct group **" result );
-.fi
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.ad l
-.in
-.sp
-.BR getgrnam_r (),
-.BR getgrgid_r ():
-.RS 4
-_POSIX_C_SOURCE\ >=\ 1 || _XOPEN_SOURCE || _BSD_SOURCE ||
-_SVID_SOURCE || _POSIX_SOURCE
-.RE
-.ad b
-.SH DESCRIPTION
-The
-.BR getgrnam ()
-function returns a pointer to a structure containing
-the broken-out fields of the record in the group database
-(e.g., the local group file
-.IR /etc/group ,
-NIS, and LDAP)
-that matches the group name
-.IR name .
-.PP
-The
-.BR getgrgid ()
-function returns a pointer to a structure containing
-the broken-out fields of the record in the group database
-that matches the group ID
-.IR gid .
-.PP
-The \fIgroup\fP structure is defined in \fI<grp.h>\fP as follows:
-.sp
-.in +4n
-.nf
-struct group {
- char *gr_name; /* group name */
- char *gr_passwd; /* group password */
- gid_t gr_gid; /* group ID */
- char **gr_mem; /* NULL-terminated array of pointers
- to names of group members */
-};
-.fi
-.in
-.PP
-For more information about the fields of this structure, see
-.BR group (5).
-.PP
-The
-.BR getgrnam_r ()
-and
-.BR getgrgid_r ()
-functions obtain the same information as
-.BR getgrnam ()
-and
-.BR getgrgid (),
-but store the retrieved
-.I group
-structure
-in the space pointed to by
-.IR grp .
-The string fields pointed to by the members of the
-.I group
-structure are stored in the buffer
-.I buf
-of size
-.IR buflen .
-A pointer to the result (in case of success) or NULL (in case no entry
-was found or an error occurred) is stored in
-.IR *result .
-.PP
-The call
-
- sysconf(_SC_GETGR_R_SIZE_MAX)
-
-returns either \-1, without changing
-.IR errno ,
-or an initial suggested size for
-.IR buf .
-(If this size is too small,
-the call fails with
-.BR ERANGE ,
-in which case the caller can retry with a larger buffer.)
-.SH RETURN VALUE
-The
-.BR getgrnam ()
-and
-.BR getgrgid ()
-functions return a pointer to a
-.I group
-structure, or NULL if the matching entry
-is not found or an error occurs.
-If an error occurs,
-.I errno
-is set appropriately.
-If one wants to check
-.I errno
-after the call, it should be set to zero before the call.
-.LP
-The return value may point to a static area, and may be overwritten
-by subsequent calls to
-.BR getgrent (3),
-.BR getgrgid (),
-or
-.BR getgrnam ().
-(Do not pass the returned pointer to
-.BR free (3).)
-.LP
-On success,
-.BR getgrnam_r ()
-and
-.BR getgrgid_r ()
-return zero, and set
-.IR *result
-to
-.IR grp .
-If no matching group record was found,
-these functions return 0 and store NULL in
-.IR *result .
-In case of error, an error number is returned, and NULL is stored in
-.IR *result .
-.SH ERRORS
-.TP
-.BR 0 " or " ENOENT " or " ESRCH " or " EBADF " or " EPERM " or ... "
-The given
-.I name
-or
-.I gid
-was not found.
-.TP
-.B EINTR
-A signal was caught.
-.TP
-.B EIO
-I/O error.
-.TP
-.B EMFILE
-The maximum number
-.RB ( OPEN_MAX )
-of files was open already in the calling process.
-.TP
-.B ENFILE
-The maximum number of files was open already in the system.
-.TP
-.B ENOMEM
-.\" not in POSIX
-Insufficient memory to allocate
-.I group
-structure.
-.\" to allocate the group structure, or to allocate buffers
-.TP
-.B ERANGE
-Insufficient buffer space supplied.
-.SH FILES
-.TP
-.I /etc/group
-local group database file
-.SH ATTRIBUTES
-.SS Multithreading (see pthreads(7))
-The
-.BR getgrnam ()
-and
-.BR getgrgid ()
-functions are not thread-safe.
-.LP
-The
-.BR getgrnam_r ()
-and
-.BR getgrgid_r ()
-functions are thread-safe.
-.SH CONFORMING TO
-SVr4, 4.3BSD, POSIX.1-2001.
-.SH NOTES
-The formulation given above under "RETURN VALUE" is from POSIX.1-2001.
-It does not call "not found" an error, hence does not specify what value
-.I errno
-might have in this situation.
-But that makes it impossible to recognize
-errors.
-One might argue that according to POSIX
-.I errno
-should be left unchanged if an entry is not found.
-Experiments on various
-UNIX-like systems shows that lots of different values occur in this
-situation: 0, ENOENT, EBADF, ESRCH, EWOULDBLOCK, EPERM, and probably others.
-.\" more precisely:
-.\" AIX 5.1 - gives ESRCH
-.\" OSF1 4.0g - gives EWOULDBLOCK
-.\" libc, glibc up to version 2.6, Irix 6.5 - give ENOENT
-.\" glibc since version 2.7 - give 0
-.\" FreeBSD 4.8, OpenBSD 3.2, NetBSD 1.6 - give EPERM
-.\" SunOS 5.8 - gives EBADF
-.\" Tru64 5.1b, HP-UX-11i, SunOS 5.7 - give 0
-.SH SEE ALSO
-.BR endgrent (3),
-.BR fgetgrent (3),
-.BR getgrent (3),
-.BR getpwnam (3),
-.BR setgrent (3),
-.BR group (5)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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