xref: /minix3/lib/libc/stdlib/bsearch.3 (revision 2fe8fb192fe7e8720e3e7a77f928da545e872a6a)
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34*2fe8fb19SBen Gras.\"     from: @(#)bsearch.3	8.3 (Berkeley) 4/19/94
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36*2fe8fb19SBen Gras.Dd April 19, 1994
37*2fe8fb19SBen Gras.Dt BSEARCH 3
38*2fe8fb19SBen Gras.Os
39*2fe8fb19SBen Gras.Sh NAME
40*2fe8fb19SBen Gras.Nm bsearch
41*2fe8fb19SBen Gras.Nd binary search of a sorted table
42*2fe8fb19SBen Gras.Sh LIBRARY
43*2fe8fb19SBen Gras.Lb libc
44*2fe8fb19SBen Gras.Sh SYNOPSIS
45*2fe8fb19SBen Gras.In stdlib.h
46*2fe8fb19SBen Gras.Ft void *
47*2fe8fb19SBen Gras.Fn bsearch "const void *key" "const void *base" "size_t nmemb" "size_t size" "int (*compar) (const void *, const void *)"
48*2fe8fb19SBen Gras.Sh DESCRIPTION
49*2fe8fb19SBen GrasThe
50*2fe8fb19SBen Gras.Fn bsearch
51*2fe8fb19SBen Grasfunction searches an array of
52*2fe8fb19SBen Gras.Fa nmemb
53*2fe8fb19SBen Grasobjects, the initial member of which is
54*2fe8fb19SBen Graspointed to by
55*2fe8fb19SBen Gras.Fa base ,
56*2fe8fb19SBen Grasfor a member that matches the object pointed to by
57*2fe8fb19SBen Gras.Fa key .
58*2fe8fb19SBen GrasThe size of each member of the array is specified by
59*2fe8fb19SBen Gras.Fa size .
60*2fe8fb19SBen Gras.Pp
61*2fe8fb19SBen GrasThe contents of the array should be in ascending sorted order according
62*2fe8fb19SBen Grasto the comparison function referenced by
63*2fe8fb19SBen Gras.Fa compar .
64*2fe8fb19SBen GrasThe
65*2fe8fb19SBen Gras.Fa compar
66*2fe8fb19SBen Grasroutine
67*2fe8fb19SBen Grasis expected to have
68*2fe8fb19SBen Grastwo arguments which point to the
69*2fe8fb19SBen Gras.Fa key
70*2fe8fb19SBen Grasobject and to an array member, in that order, and should return an integer
71*2fe8fb19SBen Grasless than, equal to, or greater than zero if the
72*2fe8fb19SBen Gras.Fa key
73*2fe8fb19SBen Grasobject is found, respectively, to be less than, to match, or be
74*2fe8fb19SBen Grasgreater than the array member.
75*2fe8fb19SBen Gras.Sh RETURN VALUES
76*2fe8fb19SBen GrasThe
77*2fe8fb19SBen Gras.Fn bsearch
78*2fe8fb19SBen Grasfunction returns a pointer to a matching member of the array, or a null
79*2fe8fb19SBen Graspointer if no match is found.
80*2fe8fb19SBen GrasIf two members compare as equal, which member is matched is unspecified.
81*2fe8fb19SBen Gras.Sh SEE ALSO
82*2fe8fb19SBen Gras.Xr db 3 ,
83*2fe8fb19SBen Gras.Xr lsearch 3 ,
84*2fe8fb19SBen Gras.Xr qsort 3 ,
85*2fe8fb19SBen Gras.Xr tsearch 3
86*2fe8fb19SBen Gras.Sh STANDARDS
87*2fe8fb19SBen GrasThe
88*2fe8fb19SBen Gras.Fn bsearch
89*2fe8fb19SBen Grasfunction conforms to
90*2fe8fb19SBen Gras.St -ansiC .
91