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JudySL_funcs(3)       DragonFly Library Functions Manual       JudySL_funcs(3)


NAME

       JudySL functions - C library for creating and accessing a dynamic
       array, using a null-terminated string as an index (associative array)


SYNOPSIS

       PPvoid_t JudySLIns(      PPvoid_t PPJSLArray, const uint8_t * Index, PJError_t PJError);
       int      JudySLDel(      PPvoid_t PPJSLArray, const uint8_t * Index, PJError_t PJError);
       PPvoid_t JudySLGet(      Pcvoid_t  PJSLArray, const uint8_t * Index, PJError_t PJError);
       Word_t   JudySLFreeArray(PPvoid_t PPJSLArray, PJError_t PJError);
       PPvoid_t JudySLFirst(    Pcvoid_t  PJSLArray,       uint8_t * Index, PJError_t PJError);
       PPvoid_t JudySLNext(     Pcvoid_t  PJSLArray,       uint8_t * Index, PJError_t PJError);
       PPvoid_t JudySLLast(     Pcvoid_t  PJSLArray,       uint8_t * Index, PJError_t PJError);
       PPvoid_t JudySLPrev(     Pcvoid_t  PJSLArray,       uint8_t * Index, PJError_t PJError);


DESCRIPTION

       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 JudySL functions.  See JudySL(3) for more information.  The
       function call definitions are included here for completeness.

       One of the difficulties in using the JudySL function calls lies in
       determining whether to pass a pointer or the address of a pointer.
       Since the functions that modify the JudySL array must also modify the
       pointer to the JudySL 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 JudySL 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 JudySL functions when an error occurs.

       Notice the placement of the & in the different functions.

        JudySLIns(&PJSLArray, Index, &JError)

                      #define JSLI(PValue, PJSLArray, Index) \
                         PValue = JudyLIns(&PJSLArray, Index, PJE0)

        JudySLDel(&PJSLArray, Index, &JError)

                      #define JSLD(Rc_int, PJSLArray, Index) \
                         Rc_int = JudySLDel(&PJSLArray, Index, PJE0)

        JudySLGet(PJSLArray, Index, &JError)

                      #define JSLG(PValue, PJSLArray, Index) \
                         PValue = JudySLIns(PJSLArray, Index, PJE0)

        JudySLFreeArray(&PJSLArray, &JError)

                      #define JSLFA(Rc_word, PJSLArray) \
                         Rc_word = JudySLFreeArray(&PJSLArray, PJE0)

        JudySLFirst(PJSLArray, Index, &JError)

                      #define JSLF(PValue, PJSLArray, Index) \
                         PValue = JudySLFirst(PJSLArray, Index, PJE0)

        JudySLNext(PJSLArray, Index, &JError)

                      #define JSLN(PValue, PJSLArray, Index) \
                         PValue = JudySLNext(PJSLArray, Index, PJE0)

        JudySLLast(PJSLArray, Index, &JError)

                      #define JSLL(PValue, PJSLArray, Index) \
                         PValue = JudySLLast(PJSLArray, Index, PJE0)

        JudySLPrev(PJSLArray, Index, &JError)

                      #define JSLP(PValue, PJSLArray, Index) \
                         PValue = JudySLPrev(PJSLArray, Index, PJE0)

       Definitions for all the Judy functions, the types Pvoid_t, Pcvoid_t,
       PPvoid_t, Word_t , JError_t, and PJError_t, the constants NULL,
       JU_ERRNO_*, JERR, PPJERR, and PJE0 are provided in the Judy.h header
       file (/usr/include/Judy.h).  Note:  Callers should define JudySL 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
       PPvoid_t.

       The return type from most JudySL functions is PPvoid_t so that the
       values stored in the array can be pointers to other objects, which is a
       typical usage, or cast to a Word_t  * when a pointer to a value is
       required instead of a pointer to a pointer.


AUTHOR

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


SEE ALSO

       Judy(3), Judy1(3), JudyL(3), JudySL(3), JudyHS(3),
       malloc(),
       the Judy website, http://judy.sourceforge.net, for more information and
       Application Notes.

                                                               JudySL_funcs(3)

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