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cfg_subsys_state

Section: C Library Functions (3)
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NAME

cfg_subsys_state - Determine the state of the named subsystem  

LIBRARY

Configuration Management Library (libcfg.a)  

SYNOPSIS

#include <cfg.h> cfg_status_t cfg_subsys_state(
        cfg_handle_t *handle,
        caddr_t subsys,
        unsigned int *state);  

PARAMETERS

Structure identifying the means of communication between your application and the configuration management server. For local requests, pass NULL in this parameter. For remote requests, pass the value you receive when you call the cfg_connect() routine. Specifies the name of the subsystem for which you are requesting state information. Returns a collection of bit flags representing the state of the subsystem. The bit flags are defined in the <sys/sysconfig.h> header file. The following flags are currently defined: CFG_STATE_CONFIGURED, CFG_STATE_DYNAMIC, and CFG_STATE_LOADED.  

DESCRIPTION

Use the cfg_subsys_state() routine to determine the state of a particular subsystem. Subsystems can be loaded, loaded and configured, or unloaded. (Subsystems must be loaded to be configured.) In addition, a subsystem can be either static (the CFG_STATE_DYNAMIC bit flag is not set) or dynamic (the CFG_STATE_DYNAMIC bit flag is set). Static subsystems are linked into the kernel at build time and the only way to add or remove them from the kernel is to rebuild the kernel. Dynamic subsystems are loadable, meaning that they can be added and removed from the kernel while the system is running.

The value returned in the state parameter is an integer representation of a binary value. The bits in the value designate the state of the subsystem. For example, the least significant bit designates whether or not the subsystem is loaded. If this bit is set, the subsystem is loaded. If the next higher order bit is set, the subsystem is configured. You can determine the state of a subsystem by using the value returned in the state parameter in a bitwise AND operation. The <sys/sysconfig.h> header file defines constants for this purpose. See the EXAMPLES section for more information about using these constants.  

EXAMPLES

The following example illustrates the use of the cfg_subsys_state() library routine:

cfg_status_t retval; cfg_handle_t handle; unsigned int state;

retval = cfg_subsys_state(&handle, "presto", &state);

if (retval != CFG_SUCCESS)
   print_error(retval); else {


     /*   Determine whether or not the subsystem is loaded           */
     /*   and configured.  Display a message describing the          */
     /*   subsystem state.                                           */


     if (state & CFG_STATE_LOADED) {
        if (state & CFG_STATE_CONFIGURED)
           printf("The subsystem is loaded and configured.\n");
        else
           printf("The subsystem is loaded but not configured.\n");
     else
        printf("The subsystem is unloaded.\n");
     } }

In this example, the cfg_subsys_state() routine returns a value representing the state of the presto subsystem. The application determines whether the call to the routine was successful and, if it was, displays a message describing the state of the subsystem.  

RETURN VALUES

Upon successful completion, cfg_subsys_state() returns CFG_SUCCESS. Other return values indicate that an error has occurred. For information about handling return values from routines in the configuration management library, see libcfg(3).  

RELATED INFORMATION

Commands: cfgmgr(8), sysconfig(8)

Routines: cfg_subsys_list(3), libcfg(3) delim off


 

Index

NAME
LIBRARY
SYNOPSIS
PARAMETERS
DESCRIPTION
EXAMPLES
RETURN VALUES
RELATED INFORMATION

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Time: 02:41:59 GMT, October 02, 2010