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cfg_subsys_state(3)
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
  handle    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.

  subsys    Specifies the name of the subsystem for which you are requesting
	    state information.

  state	    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, "vfs", &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 vfs 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)

Index for Section 3

Alphabetical listing for C

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