| 1 | /* Declarations for System V style searching functions. |
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| 2 | Copyright (C) 1995-1999, 2000 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, write to the Free |
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| 17 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
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| 18 | 02111-1307 USA. */ |
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| 19 | |
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| 20 | #ifndef _SEARCH_H |
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| 21 | #define _SEARCH_H 1 |
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| 22 | |
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| 23 | #include <features.h> |
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| 24 | |
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| 25 | #define __need_size_t |
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| 26 | #include <stddef.h> |
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| 27 | |
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| 28 | __BEGIN_DECLS |
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| 29 | |
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| 30 | #if defined __USE_SVID || defined __USE_XOPEN_EXTENDED |
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| 31 | /* Prototype structure for a linked-list data structure. |
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| 32 | This is the type used by the `insque' and `remque' functions. */ |
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| 33 | |
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| 34 | # ifdef __USE_GNU |
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| 35 | struct qelem |
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| 36 | { |
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| 37 | struct qelem *q_forw; |
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| 38 | struct qelem *q_back; |
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| 39 | char q_data[1]; |
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| 40 | }; |
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| 41 | # endif |
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| 42 | |
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| 43 | |
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| 44 | /* Insert ELEM into a doubly-linked list, after PREV. */ |
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| 45 | extern void insque (void *__elem, void *__prev) __THROW; |
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| 46 | |
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| 47 | /* Unlink ELEM from the doubly-linked list that it is in. */ |
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| 48 | extern void remque (void *__elem) __THROW; |
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| 49 | #endif |
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| 50 | |
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| 51 | |
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| 52 | /* For use with hsearch(3). */ |
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| 53 | #ifndef __COMPAR_FN_T |
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| 54 | # define __COMPAR_FN_T |
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| 55 | typedef int (*__compar_fn_t) (__const void *, __const void *); |
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| 56 | |
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| 57 | # ifdef __USE_GNU |
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| 58 | typedef __compar_fn_t comparison_fn_t; |
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| 59 | # endif |
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| 60 | #endif |
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| 61 | |
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| 62 | /* Action which shall be performed in the call the hsearch. */ |
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| 63 | typedef enum |
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| 64 | { |
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| 65 | FIND, |
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| 66 | ENTER |
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| 67 | } |
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| 68 | ACTION; |
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| 69 | |
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| 70 | typedef struct entry |
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| 71 | { |
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| 72 | char *key; |
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| 73 | void *data; |
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| 74 | } |
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| 75 | ENTRY; |
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| 76 | |
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| 77 | /* Opaque type for internal use. */ |
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| 78 | struct _ENTRY; |
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| 79 | |
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| 80 | /* Family of hash table handling functions. The functions also |
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| 81 | have reentrant counterparts ending with _r. The non-reentrant |
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| 82 | functions all work on a signle internal hashing table. */ |
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| 83 | |
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| 84 | /* Search for entry matching ITEM.key in internal hash table. If |
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| 85 | ACTION is `FIND' return found entry or signal error by returning |
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| 86 | NULL. If ACTION is `ENTER' replace existing data (if any) with |
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| 87 | ITEM.data. */ |
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| 88 | extern ENTRY *hsearch (ENTRY __item, ACTION __action) __THROW; |
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| 89 | |
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| 90 | /* Create a new hashing table which will at most contain NEL elements. */ |
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| 91 | extern int hcreate (size_t __nel) __THROW; |
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| 92 | |
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| 93 | /* Destroy current internal hashing table. */ |
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| 94 | extern void hdestroy (void) __THROW; |
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| 95 | |
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| 96 | #ifdef __USE_GNU |
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| 97 | /* Data type for reentrant functions. */ |
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| 98 | struct hsearch_data |
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| 99 | { |
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| 100 | struct _ENTRY *table; |
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| 101 | unsigned int size; |
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| 102 | unsigned int filled; |
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| 103 | }; |
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| 104 | |
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| 105 | /* Reentrant versions which can handle multiple hashing tables at the |
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| 106 | same time. */ |
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| 107 | extern int hsearch_r (ENTRY __item, ACTION __action, ENTRY **__retval, |
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| 108 | struct hsearch_data *__htab) __THROW; |
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| 109 | extern int hcreate_r (size_t __nel, struct hsearch_data *__htab) __THROW; |
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| 110 | extern void hdestroy_r (struct hsearch_data *__htab) __THROW; |
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| 111 | #endif |
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| 112 | |
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| 113 | |
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| 114 | /* The tsearch routines are very interesting. They make many |
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| 115 | assumptions about the compiler. It assumes that the first field |
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| 116 | in node must be the "key" field, which points to the datum. |
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| 117 | Everything depends on that. */ |
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| 118 | /* For tsearch */ |
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| 119 | typedef enum |
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| 120 | { |
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| 121 | preorder, |
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| 122 | postorder, |
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| 123 | endorder, |
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| 124 | leaf |
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| 125 | } |
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| 126 | VISIT; |
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| 127 | |
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| 128 | /* Search for an entry matching the given KEY in the tree pointed to |
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| 129 | by *ROOTP and insert a new element if not found. */ |
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| 130 | extern void *tsearch (__const void *__key, void **__rootp, |
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| 131 | __compar_fn_t __compar); |
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| 132 | |
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| 133 | /* Search for an entry matching the given KEY in the tree pointed to |
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| 134 | by *ROOTP. If no matching entry is available return NULL. */ |
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| 135 | extern void *tfind (__const void *__key, void *__const *__rootp, |
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| 136 | __compar_fn_t __compar); |
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| 137 | |
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| 138 | /* Remove the element matching KEY from the tree pointed to by *ROOTP. */ |
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| 139 | extern void *tdelete (__const void *__restrict __key, |
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| 140 | void **__restrict __rootp, |
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| 141 | __compar_fn_t __compar); |
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| 142 | |
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| 143 | #ifndef __ACTION_FN_T |
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| 144 | # define __ACTION_FN_T |
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| 145 | typedef void (*__action_fn_t) (__const void *__nodep, VISIT __value, |
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| 146 | int __level); |
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| 147 | #endif |
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| 148 | |
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| 149 | /* Walk through the whole tree and call the ACTION callback for every node |
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| 150 | or leaf. */ |
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| 151 | extern void twalk (__const void *__root, __action_fn_t __action); |
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| 152 | |
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| 153 | #ifdef __USE_GNU |
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| 154 | /* Callback type for function to free a tree node. If the keys are atomic |
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| 155 | data this function should do nothing. */ |
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| 156 | typedef void (*__free_fn_t) (void *__nodep); |
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| 157 | |
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| 158 | /* Destroy the whole tree, call FREEFCT for each node or leaf. */ |
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| 159 | extern void tdestroy (void *__root, __free_fn_t __freefct); |
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| 160 | #endif |
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| 161 | |
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| 162 | |
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| 163 | /* Perform linear search for KEY by comparing by COMPAR in an array |
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| 164 | [BASE,BASE+NMEMB*SIZE). */ |
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| 165 | extern void *lfind (__const void *__key, __const void *__base, |
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| 166 | size_t *__nmemb, size_t __size, __compar_fn_t __compar); |
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| 167 | |
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| 168 | /* Perform linear search for KEY by comparing by COMPAR function in |
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| 169 | array [BASE,BASE+NMEMB*SIZE) and insert entry if not found. */ |
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| 170 | extern void *lsearch (__const void *__key, void *__base, |
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| 171 | size_t *__nmemb, size_t __size, __compar_fn_t __compar); |
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| 172 | |
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| 173 | __END_DECLS |
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| 174 | |
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| 175 | #endif /* search.h */ |
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