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       Judy1  functions - C library for creating and accessing a dynamic array
       of bits, using any value of a word as an index


       int    Judy1Set(       PPvoid_t PPJ1Array, Word_t   Index,  PJError_t PJError);
       int    Judy1Unset(     PPvoid_t PPJ1Array, Word_t   Index,  PJError_t PJError);
       int    Judy1Test(      Pcvoid_t  PJ1Array, Word_t   Index,  PJError_t PJError);
       Word_t Judy1Count(     Pcvoid_t  PJ1Array, Word_t   Index1, Word_t    Index2, PJError_t PJError);
       int    Judy1ByCount(   Pcvoid_t  PJ1Array, Word_t   Nth,    Word_t * PIndex,  PJError_t PJError);
       Word_t Judy1FreeArray( PPvoid_t PPJ1Array, PJError_t PJError);
       Word_t Judy1MemUsed(   Pcvoid_t  PJ1Array);
       int    Judy1First(     Pcvoid_t  PJ1Array, Word_t * PIndex, PJError_t PJError);
       int    Judy1Next(      Pcvoid_t  PJ1Array, Word_t * PIndex, PJError_t PJError);
       int    Judy1Last(      Pcvoid_t  PJ1Array, Word_t * PIndex, PJError_t PJError);
       int    Judy1Prev(      Pcvoid_t  PJ1Array, Word_t * PIndex, PJError_t PJError);
       int    Judy1FirstEmpty(Pcvoid_t  PJ1Array, Word_t * PIndex, PJError_t PJError);
       int    Judy1NextEmpty( Pcvoid_t  PJ1Array, Word_t * PIndex, PJError_t PJError);
       int    Judy1LastEmpty( Pcvoid_t  PJ1Array, Word_t * PIndex, PJError_t PJError);
       int    Judy1PrevEmpty( Pcvoid_t  PJ1Array, Word_t * PIndex, PJError_t PJError);


       A macro equivalent exists for each function call.   Because  the  macro
       forms  are sometimes faster and have a simpler error handling interface
       than the equivalent functions, they are the preferred  way  of  calling
       the  Judy1 functions.  See Judy1(3) for more information.  The function
       call definitions are included here for completeness.

       One of the difficulties in using  the  Judy1  function  calls  lies  in
       determining  whether  to  pass  a  pointer or the address of a pointer.
       Since the functions that modify the Judy1 array must  also  modify  the
       pointer  to  the  Judy1 array, you must pass the address of the pointer
       rather than the pointer itself.   This  often  leads  to  hard-to-debug
       programmatic  errors.   In  practice,  the macros allow the compiler to
       catch programming errors when pointers instead of addresses of pointers
       are passed.

       The  Judy1  function  calls  have  an additional parameter beyond those
       specified in the macro calls.  This parameter is either a pointer to an
       error  structure, or NULL (in which case the detailed error information
       is not returned).

       In the following descriptions, the functions are described in terms  of
       how  the  macros use them (only in the case of #define JUDYERROR_NOTEST
       1).  This is the suggested use of the macros  after  your  program  has
       been fully debugged.  When the JUDYERROR_NOTEST macro is not specified,
       an error structure is declared to store error information returned from
       the Judy1 functions when an error occurs.

       Notice the placement of the & in the different functions.

        Judy1Set(&PJ1Array, Index, &JError)

                      #define J1S(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1Set(&PJ1Array, Index, PJE0)

        Judy1Unset(&PJ1Array, Index, &JError)

                      #define J1U(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1Unset(&PJ1Array, Index, PJE0)

        Judy1Test(PJ1Array, Index, &JError)

                      #define J1T(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1Test(PJ1Array, Index, PJE0)

        Judy1Count(PJ1Array, Index1, Index2, &JError)

                      #define J1C(Rc_word, PJ1Array, Index1, Index2) \
                         Rc_word = Judy1Count(PJ1Array, Index1, Index2, PJE0)

                      A  return  value of 0 can be an error, valid as a count,
                      or it can indicate a special case for a  fully-populated
                      array   (32-bit   machines  only).   If  necessary,  the
                      following code can be used to disambiguate this return:

                      JError_t JError;

                      Rc_word = Judy1Count(PJ1Array, Index1, Index2, &JError);
                      if (Rc_word == 0)
                          if (JU_ERRNO(&JError) == JU_ERRNO_NONE)
                              printf("Judy1 array population == 0\n");
                          if (JU_ERRNO(&JError) == JU_ERRNO_FULL)
                              printf("Judy1 array population == 2^32\n");
                          if (JU_ERRNO(&JError) == JU_ERRNO_NULLPPARRAY)
                              goto NullArray;
                          if (JU_ERRNO(&JError) >  JU_ERRNO_NFMAX)
                              goto Null_or_CorruptArray;

        Judy1ByCount(PJ1Array, Nth, &Index, &JError)

                      #define J1BC(Rc_int, PJ1Array, Nth, Index) \
                         Rc_int = Judy1ByCount(PJ1Array, Nth, &Index, PJE0)

        Judy1FreeArray(&PJ1Array, &JError)

                      #define J1FA(Rc_word, PJ1Array) \
                         Rc_word = Judy1FreeArray(&PJ1Array, PJE0)


                      #define J1MU(Rc_word, PJ1Array) \
                         Rc_word = Judy1MemUsed(PJ1Array)

        Judy1First(PJ1Array, &Index, &JError)

                      #define J1F(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1First(PJ1Array, &Index, PJE0)

        Judy1Next(PJ1Array, &Index, &JError)

                      #define J1N(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1Next(PJ1Array, &Index, PJE0)

        Judy1Last(PJ1Array, &Index, &JError)

                      #define J1L(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1Last(PJ1Array, &Index, PJE0)

        Judy1Prev(PJ1Array, &Index, &JError)

                      #define J1P(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1Prev(PJ1Array, &Index, PJE0)

        Judy1FirstEmpty(PJ1Array, &Index, &JError)

                      #define J1FE(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1FirstEmpty(PJ1Array, &Index, PJE0)

        Judy1NextEmpty(PJ1Array, &Index, &JError)

                      #define J1NE(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1NextEmpty(PJ1Array, &Index, PJE0)

        Judy1LastEmpty(PJ1Array, &Index, &JError)

                      #define J1LE(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1LastEmpty(PJ1Array, &Index, PJE0)

        Judy1PrevEmpty(PJ1Array, &Index, &JError)

                      #define J1PE(Rc_int, PJ1Array, Index) \
                         Rc_int = Judy1PrevEmpty(PJ1Array, &Index, PJE0)

       Definitions for all of the Judy functions, the types Pvoid_t, Pcvoid_t,
       PPvoid_t,   Word_t,   JError_t,  and  PJError_t,  the  constants  NULL,
       JU_ERRNO_*, JERR, and PJE0, are provided  in  the  Judy.h  header  file
       (/usr/include/Judy.h).   Note:   Callers  should define Judy1 arrays as
       type Pvoid_t, which can be passed  by  value  to  functions  that  take
       Pcvoid_t (constant Pvoid_t), and also by address to functions that take


       Judy was invented by Doug Baskins and implemented by Hewlett-Packard.


       Judy(3), JudyL(3), JudySL(3), JudyHS(3),
       the Judy website,, for more information and
       Application Notes.