123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105 |
- .\" Copyright (c) 1983, 1991, 1993
- .\" The Regents of the University of California. All rights reserved.
- .\"
- .\" Redistribution and use in source and binary forms, with or without
- .\" modification, are permitted provided that the following conditions
- .\" are met:
- .\" 1. Redistributions of source code must retain the above copyright
- .\" notice, this list of conditions and the following disclaimer.
- .\" 2. Redistributions in binary form must reproduce the above copyright
- .\" notice, this list of conditions and the following disclaimer in the
- .\" documentation and/or other materials provided with the distribution.
- .\" 3. Neither the name of the University nor the names of its contributors
- .\" may be used to endorse or promote products derived from this software
- .\" without specific prior written permission.
- .\"
- .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- .\" SUCH DAMAGE.
- .\"
- .Dd January 21, 2011
- .Dt GETGROUPS 2
- .Os
- .Sh NAME
- .Nm getgroups
- .Nd get group access list
- .Sh LIBRARY
- .Lb libc
- .Sh SYNOPSIS
- .In unistd.h
- .Ft int
- .Fn getgroups "int gidsetlen" "gid_t *gidset"
- .Sh DESCRIPTION
- The
- .Fn getgroups
- system call
- gets the current group access list of the user process
- and stores it in the array
- .Fa gidset .
- The
- .Fa gidsetlen
- argument
- indicates the number of entries that may be placed in
- .Fa gidset .
- The
- .Fn getgroups
- system call
- returns the actual number of groups returned in
- .Fa gidset .
- At least one and as many as {NGROUPS_MAX}+1 values may be returned.
- If
- .Fa gidsetlen
- is zero,
- .Fn getgroups
- returns the number of supplementary group IDs associated with
- the calling process without modifying the array pointed to by
- .Fa gidset .
- .Pp
- The value of
- .Dv {NGROUPS_MAX}
- should be obtained using
- .Xr sysconf 3
- to avoid hard-coding it into the executable.
- .Sh RETURN VALUES
- A successful call returns the number of groups in the group set.
- A value of -1 indicates that an error occurred, and the error
- code is stored in the global variable
- .Va errno .
- .Sh ERRORS
- The possible errors for
- .Fn getgroups
- are:
- .Bl -tag -width Er
- .It Bq Er EINVAL
- The argument
- .Fa gidsetlen
- is smaller than the number of groups in the group set.
- .It Bq Er EFAULT
- The argument
- .Fa gidset
- specifies
- an invalid address.
- .El
- .Sh SEE ALSO
- .Xr setgroups 2 ,
- .Xr initgroups 3 ,
- .Xr sysconf 3
- .Sh STANDARDS
- The
- .Fn getgroups
- system call conforms to
- .St -p1003.1-2008 .
- .Sh HISTORY
- The
- .Fn getgroups
- system call appeared in
- .Bx 4.2 .
|