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LDAP_FIRST_ATTRIBUTE(3)    Library Functions Manual    LDAP_FIRST_ATTRIBUTE(3)

NAME
       ldap_first_attribute, ldap_next_attribute - step through LDAP entry
       attributes

LIBRARY
       OpenLDAP LDAP (libldap, -lldap)

SYNOPSIS
       #include <ldap.h>

       char *ldap_first_attribute(
            LDAP *ld, LDAPMessage *entry, BerElement **berptr )

       char *ldap_next_attribute(
            LDAP *ld, LDAPMessage *entry, BerElement *ber )

       int ldap_get_attribute_ber(
            LDAP *ld, LDAPMessage *entry, BerElement *ber,
            BerValue *attr, BerVarray *vals )

DESCRIPTION
       The ldap_first_attribute(), ldap_next_attribute() and
       ldap_get_attribute_ber() routines are used to step through the
       attributes in an LDAP entry.  ldap_first_attribute() takes an entry as
       returned by ldap_first_entry(3) or ldap_next_entry(3) and returns a
       pointer to character string containing the first attribute description
       in the entry.  ldap_next_attribute() returns the next attribute
       description in the entry.

       It also returns, in berptr, a pointer to a BerElement it has allocated
       to keep track of its current position.  This pointer should be passed
       to subsequent calls to ldap_next_attribute() and is used to effectively
       step through the entry's attributes.  The caller is solely responsible
       for freeing the BerElement pointed to by berptr when it is no longer
       needed by calling ber_free(3).  When calling ber_free(3) in this
       instance, be sure the second argument is 0.

       The attribute names returned are suitable for inclusion in a call to
       ldap_get_values(3) to retrieve the attribute's values.

       The ldap_get_attribute_ber() routine allows one to iterate over all
       attributes in-place, without allocating memory to hold text for the
       attribute name or its values, if requested. The use case is similar to
       ldap_next_attribute() except that the attribute name is returned into
       attr and, if vals is non-NULL, the list of values is stored there. Both
       point into the LDAP message and remain valid only while the entry is
       valid.  The caller is still responsible for freeing vals with
       ldap_memfree(3), if used.

ERRORS
       If an error occurs, NULL is returned and the ld_errno field in the ld
       parameter is set to indicate the error.  See ldap_error(3) for a
       description of possible error codes.

NOTES
       The ldap_first_attribute() and ldap_next_attribute() return dynamically
       allocated memory that must be freed by the caller via ldap_memfree(3).
       For ldap_get_attribute_ber(), only the actual vals pointer needs to be
       freed with ldap_memfree(3), other data is accounted for as part of ber.

SEE ALSO
       ldap(3), ldap_first_entry(3), ldap_get_values(3), ldap_error(3)

ACKNOWLEDGEMENTS
       OpenLDAP Software is developed and maintained by The OpenLDAP Project
       <http://www.openldap.org/>.  OpenLDAP Software is derived from the
       University of Michigan LDAP 3.3 Release.

OpenLDAP 2.6.10                   2025/05/22           LDAP_FIRST_ATTRIBUTE(3)