diff options
Diffstat (limited to 'src/lib/libc/stdlib/tsearch.3')
| -rw-r--r-- | src/lib/libc/stdlib/tsearch.3 | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/src/lib/libc/stdlib/tsearch.3 b/src/lib/libc/stdlib/tsearch.3 new file mode 100644 index 0000000000..15d7b84a3a --- /dev/null +++ b/src/lib/libc/stdlib/tsearch.3 | |||
| @@ -0,0 +1,116 @@ | |||
| 1 | .\" $OpenBSD: tsearch.3,v 1.12 2003/06/17 21:56:24 millert Exp $ | ||
| 2 | .\" | ||
| 3 | .\" Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com> | ||
| 4 | .\" | ||
| 5 | .\" Permission to use, copy, modify, and distribute this software for any | ||
| 6 | .\" purpose with or without fee is hereby granted, provided that the above | ||
| 7 | .\" copyright notice and this permission notice appear in all copies. | ||
| 8 | .\" | ||
| 9 | .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | ||
| 10 | .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | ||
| 11 | .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | ||
| 12 | .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | ||
| 13 | .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | ||
| 14 | .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | ||
| 15 | .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | ||
| 16 | .\" | ||
| 17 | .Dd June 15, 1997 | ||
| 18 | .Dt TSEARCH 3 | ||
| 19 | .Os | ||
| 20 | .Sh NAME | ||
| 21 | .Nm tsearch , | ||
| 22 | .Nm tfind , | ||
| 23 | .Nm tdelete , | ||
| 24 | .Nm twalk | ||
| 25 | .Nd manipulate binary search trees | ||
| 26 | .Sh SYNOPSIS | ||
| 27 | .Fd #include <search.h> | ||
| 28 | .Ft void * | ||
| 29 | .Fn tdelete "const void *key" "void **rootp" "int (*compar) (const void *, const void *)" | ||
| 30 | .Ft void * | ||
| 31 | .Fn tfind "const void *key" "void * const *rootp" "int (*compar) (const void *, const void *)" | ||
| 32 | .Ft void * | ||
| 33 | .Fn tsearch "const void *key" "void **rootp" "int (*compar) (const void *, const void *)" | ||
| 34 | .Ft void | ||
| 35 | .Fn twalk "const void *root" "void (*action) (const void *, VISIT, int)" | ||
| 36 | .Sh DESCRIPTION | ||
| 37 | The | ||
| 38 | .Fn tdelete , | ||
| 39 | .Fn tfind , | ||
| 40 | .Fn tsearch , | ||
| 41 | and | ||
| 42 | .Fn twalk | ||
| 43 | functions manage binary search trees based on algorithms T and D | ||
| 44 | from Knuth (6.2.2). | ||
| 45 | The comparison function passed in by | ||
| 46 | the user has the same style of return values as | ||
| 47 | .Xr strcmp 3 . | ||
| 48 | .Pp | ||
| 49 | .Fn tfind | ||
| 50 | searches for the datum matched by the argument | ||
| 51 | .Fa key | ||
| 52 | in the binary tree rooted at | ||
| 53 | .Fa rootp , | ||
| 54 | returning a pointer to the datum if it is found and | ||
| 55 | .Dv NULL | ||
| 56 | if it is not. | ||
| 57 | .Pp | ||
| 58 | .Fn tsearch | ||
| 59 | is identical to | ||
| 60 | .Fn tfind | ||
| 61 | except that if no match is found, | ||
| 62 | .Fa key | ||
| 63 | is inserted into the tree and a pointer to it is returned. | ||
| 64 | If | ||
| 65 | .Fa rootp | ||
| 66 | points to a null value a new binary search tree is created. | ||
| 67 | .Pp | ||
| 68 | .Fn tdelete | ||
| 69 | deletes a node from the specified binary search tree and returns | ||
| 70 | a pointer to the parent of the node to be deleted. | ||
| 71 | It takes the same arguments as | ||
| 72 | .Fn tfind | ||
| 73 | and | ||
| 74 | .Fn tsearch . | ||
| 75 | If the node to be deleted is the root of the binary search tree, | ||
| 76 | .Fa rootp | ||
| 77 | will be adjusted. | ||
| 78 | .Pp | ||
| 79 | .Fn twalk | ||
| 80 | walks the binary search tree rooted in | ||
| 81 | .Fa root | ||
| 82 | and calls the function | ||
| 83 | .Fa action | ||
| 84 | on each node. | ||
| 85 | .Fa action | ||
| 86 | is called with three arguments: a pointer to the current node, | ||
| 87 | a value from the enum | ||
| 88 | .Sy "typedef enum { preorder, postorder, endorder, leaf } VISIT;" | ||
| 89 | specifying the traversal type, and a node level (where level | ||
| 90 | zero is the root of the tree). | ||
| 91 | .Sh RETURN VALUES | ||
| 92 | The | ||
| 93 | .Fn tsearch | ||
| 94 | function returns | ||
| 95 | .Dv NULL | ||
| 96 | if allocation of a new node fails (usually | ||
| 97 | due to a lack of free memory). | ||
| 98 | .Pp | ||
| 99 | .Fn tfind , | ||
| 100 | .Fn tsearch , | ||
| 101 | and | ||
| 102 | .Fn tdelete | ||
| 103 | return | ||
| 104 | .Dv NULL | ||
| 105 | if | ||
| 106 | .Fa rootp | ||
| 107 | is | ||
| 108 | .Dv NULL | ||
| 109 | or the datum cannot be found. | ||
| 110 | .Pp | ||
| 111 | The | ||
| 112 | .Fn twalk | ||
| 113 | function returns no value. | ||
| 114 | .Sh SEE ALSO | ||
| 115 | .Xr bsearch 3 , | ||
| 116 | .Xr lsearch 3 | ||