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ldap_first_attribute(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ERRORS | NOTES | SEE ALSO | ACKNOWLEDGEMENTS | COLOPHON 

LDAP_FIRST_ATTRIBUTE(3)  Library Functions Manual LDAP_FIRST_ATTRIBUTE(3)

NAME         top

       ldap_first_attribute, ldap_next_attribute - step through LDAP
       entry attributes

LIBRARY         top

       OpenLDAP LDAP (libldap, -lldap)

SYNOPSIS         top

       #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         top

       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         top

       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         top

       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         top

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

ACKNOWLEDGEMENTS         top

       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.

COLOPHON         top

       This page is part of the OpenLDAP (an open source implementation
       of the Lightweight Directory Access Protocol) project.
       Information about the project can be found at 
       ⟨http://www.openldap.org/⟩.  If you have a bug report for this
       manual page, see ⟨http://www.openldap.org/its/⟩.  This page was
       obtained from the project's upstream Git repository
       ⟨https://git.openldap.org/openldap/openldap.git⟩ on 2025-08-11.
       (At that time, the date of the most recent commit that was found
       in the repository was 2025-08-05.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there is
       a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

OpenLDAP LDVERSION             RELEASEDATE        LDAP_FIRST_ATTRIBUTE(3)

Pages that refer to this page: ldap(3),  ldap_first_entry(3),  ldap_get_values(3),  ldap_sync(3)

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