JudySL_funcs(3X)JudySL_funcs(3X)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 char * Index, PJError_t PJError);
int JudySLDel( PPvoid_t PPJSLArray, const char * Index, PJError_t PJError);
PPvoid_t JudySLGet( Pcvoid_t PJSLArray, const char * Index, PJError_t PJError);
Word_t JudySLFreeArray(PPvoid_t PPJSLArray, PJError_t PJError);
PPvoid_t JudySLFirst( Pcvoid_t PJSLArray, char * Index, PJError_t PJError);
PPvoid_t JudySLNext( Pcvoid_t PJSLArray, char * Index, PJError_t PJError);
PPvoid_t JudySLLast( Pcvoid_t PJSLArray, char * Index, PJError_t PJError);
PPvoid_t JudySLPrev( Pcvoid_t PJSLArray, char * Index, PJError_t PJError);
DESCRIPTION
A macro equivalent exists for each function call. Because the macro
forms are faster and have a simpler error handling interface than the
equivalent functions, they are the preferred way of calling the JudySL
functions. See JudySL(3X) 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 pro‐
grammatic 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.
#define JSLI(PValue, PJSLArray, Index) \
PValue = JudyLIns(&PJSLArray, Index, PJE0)
#define JSLD(Rc_int, PJSLArray, Index) \
Rc_int = JudySLDel(&PJSLArray, Index, PJE0)
#define JSLG(PValue, PJSLArray, Index) \
PValue = JudySLIns(PJSLArray, Index, PJE0)
#define JSLFA(Rc_word, PJSLArray) \
Rc_word = JudySLFreeArray(&PJSLArray, PJE0)
#define JSLF(PValue, PJSLArray, Index) \
PValue = JudySLFirst(PJSLArray, Index, PJE0)
#define JSLN(PValue, PJSLArray, Index) \
PValue = JudySLNext(PJSLArray, Index, PJE0)
#define JSLL(PValue, PJSLArray, Index) \
PValue = JudySLLast(PJSLArray, Index, PJE0)
#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 val‐
ues 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 and implemented by Hewlett-Packard.
SEE ALSOJudy(3X), Judy1(3X), Judy1_funcs(3X), JudyL(3X), JudyL_funcs(3X),
JudySL(3X),
malloc(3),
the Judy website, http://www.hp.com/go/judy/, for more information and
Application Notes.
JudySL_funcs(3X)
