Content-type: text/html Man page of getesdvent


Section: C Library Functions (3)
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getesdvent, getesdvnam, setdvagent, enddvagent, putesdvnam, copyesdvent - Manipulate device assignment database entry (Enhanced Security)  


Security Library (

NOTE: In order to quickstart a program, the program must be linked as follows:

-lsecurity -ldb -laud -lm

See the shared library discussion in the Programmer's Guide for more information about using the quickstarting feature.  


#include <sys/types.h>
#include <sys/security.h>
#include <prot.h>

struct esdev_asg *getesdvent(void);

struct esdev_asg *getesdvnam(
       char *name);

void setdvagent(void);

void enddvagent(void);

int putesdvnam(
       char *name,

       struct esdev_asg *dv);

struct esdev_asg *copyesdvent(
       struct esdev_asg *dv);


A cross-reference to the terminal control database. Contains a device assignment structure.  


The getesdvent(), getesdvnam(), and copyesdvent() functions each return a pointer to an object with the following structure containing the separated-out fields of an entry in the device assignment database. Each database entry is returned as a esdev_asg structure, declared in the prot.h header file as follows: /* Device Assignment Database entry */

struct esdev_field {
    char        *fd_name;       /* external name */
    char        **fd_devs;      /* device list */
    mask_t      *fd_type;       /* tape, printer, terminal */
    mand_ir_t   *fd_max_sl;     /* maximum sensitivity level */
    mand_ir_t   *fd_min_sl ;    /* minimum sensitivity level */
    mand_ir_t   *fd_cur_sl ;    /* currently assigned s.l. */
    ilb_ir_t    *fd_cur_il ;    /* currently assigned info l. */
    mask_t      *fd_assign;     /* single-, multilevel, etc. */
    char        **fd_users ;    /* list of users */ };

struct esdev_flag {
    unsigned int
        fg_name : 1,
        fg_devs : 1,
        fg_type : 1,
        fg_max_sl : 1,
        fg_min_sl : 1,
        fg_cur_sl : 1,
        fg_cur_il : 1,
        fg_assign : 1,
        fg_users  : 1; };

struct esdev_asg {
   size_t                  fieldlen;
   struct esdev_field      *ufld;
   struct esdev_flag       *uflg;
   struct esdev_field      *sfld;
   struct esdev_flag       *sflg; };

Each entry contains a name, which is a cross-reference to the terminal control database, and a list of devices, each of which is a pathname that corresponds to that device. The list is a table of character string pointers, whose last entry is a null pointer.

The fd_type fields are bit masks that can be manipulated with the ADDBIT(), RMBIT(), and ISBITSET() macros. The fd_users field is a pointer to a null-terminated table of character string pointers referring to user allowed access.

When the getesdvent() function is first called, it returns a pointer to the first device assignment entry. Thereafter, it returns a pointer to the next entry, so successive calls can be used to search the database. The getesdvnam() function searches from the beginning of the database until an entry with device name matching name is found, and returns a pointer to that entry. If an end-of-file or an error is encountered on reading, these functions return a null pointer.

The copyesdvent() function copies dv, and the fields to which it refers, to a newly allocated data area. Because the getesdvent(), getesdvnam(), and putesdvent() functions reuse a static structure when accessing the database, the values of any entry must be saved if the database routines are used again. The esdev_asg structure returned by copyesdvent() can be freed using the free() function.

A call to the setdvagent() function has the effect of setting the device assignment database back to the first entry, to allow repeated searches of the database. The enddvagent() function frees all memory and closes all files used to support the database routines.

The putesdvnam() function rewrites or adds an entry to the database. If there is an entry whose fd_name field matches the name argument, that entry is replaced with the contents of the dv structure. Otherwise, that entry is added to the database.  


Programs using the database routines must be compiled with -lsecurity.  


Structures returned by the database routines contain pointers to character strings and lists rather than being self-contained. The copyesdvent() function must be used rather than doing a structure assignment to save a returned structure.

The value returned by the getesdvent() and getesdvnam() functions refers to a structure that is overwritten by calls to these functions. To retrieve an entry, modify it, and replace it in the database, you must copy the entry using the copyesdvent() function and supply the modified buffer to the putesdvent() function.  


The getesdvent() and getesdvnam() functions return a pointer to a static structure on success, or a null pointer on failure. This static structure is overwritten by the getesdvent(), getesdvnam(), and putesdvnam() functions. The putesdvnam() function returns a value of 1 on success, or a value of 0 (zero) on failure. The copyesdvent() function returns a pointer to the newly allocated structure on success, or a null pointer if there was a memory allocation error.  


File containing device assignment entries.  


Functions: auth_for_terminal_es(3)

Files: authcap(4), devassign(4)

Security delim off




This document was created by man2html, using the manual pages.
Time: 02:42:13 GMT, October 02, 2010