hoverwf@126.com writes:

   when i disable the code which get the attribute value of entry,

in other word, both the for loop. this problem seems disappeared,

Yes. Add ldap_memfree(a); to your inner loop, like 'man ldap_first_attribute' says:

NOTES The ldap_first_attribute() and ldap_next_attribute() return dynamically allocated memory that must be freed by the caller via ldap_memfree(3).

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