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Full Discussion: How to avoid dangling pointers?
Top Forums Programming How to avoid dangling pointers? Post 302880518 by techmonk on Friday 20th of December 2013 06:41:43 AM
Old 12-20-2013
How to avoid dangling pointers?
To get rid of dangling pointers, after freeing the pointer, can we assign NULL. Is this be an acceptable solution. Since
Code:
free(NULL)

won't do any operation.

Code:
main(){
 void *ptr = malloc(10);
 free(ptr); 
 ptr = NULL;
 free(ptr);
}

 

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LEARN ABOUT CENTOS

slapo-memberof

SLAPO-MEMBEROF(5)						File Formats Manual						 SLAPO-MEMBEROF(5)

NAME

       slapo-memberof - Reverse Group Membership overlay to slapd

SYNOPSIS

       /etc/openldap/slapd.conf

DESCRIPTION

       The  memberof  overlay  to slapd(8) allows automatic reverse group membership maintenance.  Any time a group entry is modified, its members
       are modified as appropriate in order to keep a DN-valued "is member of" attribute updated with the DN of the group.

CONFIGURATION

       The config directives that are specific to the memberof overlay must be prefixed by memberof-, to avoid potential conflicts with directives
       specific to the underlying database or to other stacked overlays.

       overlay memberof
	      This directive adds the memberof overlay to the current database; see slapd.conf(5) for details.

       The following slapd.conf configuration options are defined for the memberof overlay.

       memberof-group-oc <group-oc>
	      The value <group-oc> is the name of the objectClass that triggers the reverse group membership update.  It defaults to groupOfNames.

       memberof-member-ad <member-ad>
	      The  value  <member-ad> is the name of the attribute that contains the names of the members in the group objects; it must be DN-val-
	      ued.  It defaults to member.

       memberof-memberof-ad <memberof-ad>
	      The value <memberof-ad> is the name of the attribute that contains the names of the groups an entry is member of; it must be DN-val-
	      ued.  Its contents are automatically updated by the overlay.  It defaults to memberOf.

       memberof-dn <dn>
	      The  value  <dn> contains the DN that is used as modifiersName for internal modifications performed to update the reverse group mem-
	      bership.	It defaults to the rootdn of the underlying database.

       memberof-dangling {ignore, drop, error}
	      This option determines the behavior of the overlay when, during a modification, it encounters dangling references.  The  default	is
	      ignore,  which  may leave dangling references.  Other options are drop, which discards those modifications that would result in dan-
	      gling references, and error, which causes modifications that would result in dangling references to fail.

       memberof-dangling-error <error-code>
	      If memberof-dangling is set to error, this configuration parameter can be used to modify the response code returned in case of  vio-
	      lation.  It defaults to "constraint violation", but other implementations are known to return "no such object" instead.

       memberof-refint {true|FALSE}
	      This  option  determines	whether the overlay will try to preserve referential integrity or not.	If set to TRUE, when an entry con-
	      taining values of the "is member of" attribute is modified, the corresponding groups are modified as well.

       The memberof overlay may be used with any backend that provides full read-write functionality, but it is mainly intended for use with local
       storage backends. The maintenance operations it performs are internal to the server on which the overlay is configured and are never repli-
       cated. Replica servers should be configured with their own instances of the memberOf overlay if it is desired to  maintain  these  memberOf
       attributes on the replicas.

FILES

       /etc/openldap/slapd.conf
	      default slapd configuration file

SEE ALSO

       slapd.conf(5), slapd-config(5), slapd(8).  The slapo-memberof(5) overlay supports dynamic configuration via back-config.

ACKNOWLEDGEMENTS

       This module was written in 2005 by Pierangelo Masarati for SysNet s.n.c.

OpenLDAP 2.4.39 						    2014/01/26							 SLAPO-MEMBEROF(5)
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