Series 200, 300, 800 Only

NAME

privgrp − format of privileged values

SYNOPSIS

#include <sys/privgrp.h>

DESCRIPTION

Setprivgrp(2) sets a mask of privileges, and getprivgrp(2) returns an array of structures giving privileged group assignments on a per group−id basis.  Privgrp.h contains the constants and structures needed to deal with these system calls, and contains:

/*
 * Privileged group definitions --
 * the numeric values may vary between implementations.
 */
#define PRIV_RTPRIO     1
#define PRIV_MLOCK      2
#define PRIV_CHOWN      3
 /* Maximum number of privileged groups in system */
#define PRIV_MAXGRPS  32
 /*
 * Size of the privilege mask,
 * based on largest numbered privilege
 */
#define PRIV_MASKSIZ  1
 /*
 * Structure defining the privilege mask
 */
struct privgrp_map {
    int    priv_groupno;
    unsigned int priv_mask[PRIV_MASKSIZ];
};

PRIV_RTPRIO allows access to the rtprio(2) system call. 
PRIV_MLOCK allows access to the plock(2) system call. 
PRIV_CHOWN allows access to the chown(2) system calls. 

Privileges are described in a multi−word mask.  The value of the #define for each privilege is interpreted as a bit index (counting from 1).  Thus a group−id may have several different privileges associated with it by having different bits or’ed into the mask. 

The system is configured with a maximum number of groups with special privileges.  PRIV_MAXGRPS defines this maximum.  Of this maximum, one is reserved for global privileges (granted to all processes), and the remainder can be assigned to actual group−ids. 

PRIV_MASKSIZ defines the size of the multi−word mask used defining privileges associated with a group−id. 

Privileges are returned to the user from the getprivgrp(2) system call in an array of structures of type struct privgrp_map.  The structure associates a multi−word mask with a group−id. 

SEE ALSO

getprivgrp(2)

Hewlett-Packard Company  —  Version B.1,  May 11, 2021