setgroups(2) [opendarwin man page]

SETGROUPS(2)						      BSD System Calls Manual						      SETGROUPS(2)

NAME

     setgroups -- set group access list

SYNOPSIS

     #include <sys/param.h>
     #include <unistd.h>

     int
     setgroups(int ngroups, const gid_t *gidset);

DESCRIPTION

     Setgroups() sets the group access list of the current user process according to the array gidset.	The parameter ngroups indicates the number
     of entries in the array and must be no more than {NGROUPS_MAX}.

     Only the super-user may set new groups.

RETURN VALUES

     A 0 value is returned on success, -1 on error, with an error code stored in errno.

ERRORS

     The setgroups() call will fail if:

     [EINVAL]		The value of ngroups is greater than {NGROUPS_MAX}.

     [EPERM]		The caller is not the super-user.

     [EFAULT]		The address specified for gidset is outside the process address space.

SEE ALSO

     getgroups(2), initgroups(3)

HISTORY

     The setgroups() function call appeared in 4.2BSD.

4.2 Berkeley Distribution					  April 16, 1994					 4.2 Berkeley Distribution

GETGROUPS(2)						      BSD System Calls Manual						      GETGROUPS(2)

NAME

     getgroups -- get group access list

SYNOPSIS

     #include <sys/param.h>
     #include <sys/types.h>
     #include <unistd.h>

     int
     getgroups(int gidsetlen, gid_t *gidset);

DESCRIPTION

     Getgroups() gets the current group access list of the current user process and stores it in the array gidset.  The parameter gidsetlen indi-
     cates the number of entries that may be placed in gidset.	Getgroups() returns the actual number of groups returned in gidset.  No more than
     {NGROUPS_MAX} will ever be returned.  If gidsetlen is 0, getgroups() returns the number of groups without modifying the gidset array.

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 errno.

ERRORS

     The possible errors for getgroups() are:

     [EINVAL]		The argument gidsetlen is smaller than the number of groups in the group set.

     [EFAULT]		The argument gidset specifies an invalid address.

SEE ALSO

     setgroups(2), initgroups(3)

HISTORY

     The getgroups() function call appeared in 4.2BSD.

4.2 Berkeley Distribution					  April 16, 1994					 4.2 Berkeley Distribution