PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding Linux  manual  page  for  details  of
       Linux behavior), or the interface may not be implemented on Linux.

NAME

       search.h — search tables

SYNOPSIS

       #include <search.h>

DESCRIPTION

       The  <search.h> header shall define the ENTRY type for structure entry which shall include
       the following members:

           char    *key
           void    *data

       and shall define ACTION and VISIT as enumeration data types through  type  definitions  as
       follows:

           enum { FIND, ENTER } ACTION;
           enum { preorder, postorder, endorder, leaf } VISIT;

       The <search.h> header shall define the size_t type as described in <sys/types.h>.

       The  following  shall be declared as functions and may also be defined as macros. Function
       prototypes shall be provided.

           int    hcreate(size_t);
           void   hdestroy(void);
           ENTRY *hsearch(ENTRY, ACTION);
           void   insque(void *, void *);
           void  *lfind(const void *, const void *, size_t *,
                     size_t, int (*)(const void *, const void *));
           void  *lsearch(const void *, void *, size_t *,
                     size_t, int (*)(const void *, const void *));
           void   remque(void *);
           void  *tdelete(const void *restrict, void **restrict,
                     int(*)(const void *, const void *));
           void  *tfind(const void *, void *const *,
                     int(*)(const void *, const void *));
           void  *tsearch(const void *, void **,
                     int(*)(const void *, const void *));
           void   twalk(const void *,
                     void (*)(const void *, VISIT, int ));

       The following sections are informative.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       <sys_types.h>

       The System Interfaces volume of POSIX.1‐2017, hcreate(), insque(), lsearch(), tdelete()

COPYRIGHT

       Portions of this text are reprinted and  reproduced  in  electronic  form  from  IEEE  Std
       1003.1-2017,  Standard  for  Information Technology -- Portable Operating System Interface
       (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C)  2018  by
       the  Institute  of  Electrical  and Electronics Engineers, Inc and The Open Group.  In the
       event of any discrepancy between this version and the original IEEE  and  The  Open  Group
       Standard,  the  original  IEEE  and  The  Open Group Standard is the referee document. The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are most  likely  to  have
       been  introduced  during  the conversion of the source files to man page format. To report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .