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43 .Nd generic hash table functions for the kernel
49 .Fn hashinit "int count" "struct malloc_type *type" "u_long *hashmask"
51 .Fn hashinit_ext "int count" "size_t size" "struct malloc_type *type" "u_long *hashmask"
53 .Fn hashdestroy "void *hashtbl" "struct malloc_type *type" "u_long hashmask"
55 .Fn phashinit "int count" "struct malloc_type *type" "u_long *nentries"
57 .Fn phashinit_ext "int count" "size_t size" "struct malloc_type *type" "u_long *nentries"
59 The kernel hash functions are used for creating a generic hash table.
63 function returns a pointer to a hash table which is sized a
65 greater or equal to the element
68 The masking value is stored in
73 function returns a pointer to a prime number sized hash table.
76 requested is used to dictate an upper-bound for the size of the
78 The final size of the hash table is stored by the function in
83 argument to both of the above functions is used for keeping track
84 of memory allocated for the hash table.
87 manual page for more information on memory statistics.
93 functions are extended versions of
99 of the structure as an additional argument and will zero the array instead
100 of assuming that it is an array of
105 function frees the space occupied by the hash table pointed to by argument
109 determines the malloc arena to use when freeing space.
112 should be the bit mask returned by the call to
114 that allocated the hash table.
117 must be used with one of the following values.
124 This manual page was written by
125 .An Hiten Pandya Aq Mt hmp@backplane.com .
131 to free a hash table allocated by
133 usually has grave consequences.