Manual Pages for UNIX Darwin command on man xdr_u

Manual Pages for UNIX Darwin command on man xdr_u_short

XDR(3) BSD Library Functions Manual XDR(3)

NAME

xxddrr, xxddrraarrrraayy, xxddrrbbooooll, xxddrrbbyytteess, xxddrrcchhaarr, xxddrrddeessttrrooyy, xxddrrddoouubbllee, xxddrreennuumm, xxddrrffllooaatt, xxddrrffrreeee, xxddrrggeettppooss, xxddrrhhyyppeerr, xxddrriinnlliinnee, xxddrriinntt, xxddrrlloonngg, xxddrrlloonngglloonnggtt, xxddrrmmeemmccrreeaattee, xxddrrooppaaqquuee, xxddrrppooiinntteerr, xxddrrrreeccccrreeaattee, xxddrrrreecceennddooffrreeccoorrdd, xxddrrrreecceeooff, xxddrrrreeccsskkiipprreeccoorrdd, xxddrrrreeffeerreennccee, xxddrrsseettppooss, xxddrrsshhoorrtt, xxddrrssttddiiooccrreeaattee, xxddrrssttrriinngg, xxddrruucchhaarr, xxddrruuhhyyppeerr, xxddrruuiinntt, xxddrruulloonngg, xxddrruulloonngglloonnggtt, xxddrruusshhoorrtt, xxddrruunniioonn, xxddrrvveeccttoorr, xxddrrvvooiidd,

xxddrrwwrraappssttrriinngg - library routines for external data representation

LLIIBBRRAARRYY

Standard C Library (libc, -lc)

SYNOPSIS

##iinncclluuddee <>

See DESCRIPTION for function declarations.

DESCRIPTION

These routines allow C programmers to describe arbitrary data structures

in a machine-independent fashion. Data for remote procedure calls are

transmitted using these routines. int xxddrraarrrraayy(XDR *xdrs, char **arrp, uint *sizep, uint maxsize, uint elsize, xdrproct elproc)

A filter primitive that translates between variable-length arrays

and their corresponding external representations. The arrp argu-

ment is the address of the pointer to the array, while sizep is the address of the element count of the array; this element count cannot exceed maxsize. The elsize argument is the ssiizzeeooff each of the array's elements, and elproc is an XDR filter that translates

between the array elements' C form, and their external represen-

tation. This routine returns one if it succeeds, zero otherwise. int xxddrrbbooooll(XDR *xdrs, boolt *bp) A filter primitive that translates between booleans (C integers) and their external representations. When encoding data, this filter produces values of either one or zero. This routine returns one if it succeeds, zero otherwise. int xxddrrbbyytteess(XDR *xdrs, char **sp, uint *sizep, uint maxsize) A filter primitive that translates between counted byte strings and their external representations. The sp argument is the address of the string pointer. The length of the string is located at address sizep; strings cannot be longer than maxsize. This routine returns one if it succeeds, zero otherwise. int xxddrrcchhaarr(XDR *xdrs, char *cp) A filter primitive that translates between C characters and their

external representations. This routine returns one if it suc-

ceeds, zero otherwise. Note: encoded characters are not packed,

and occupy 4 bytes each. For arrays of characters, it is worth-

while to consider xxddrrbbyytteess(), xxddrrooppaaqquuee() or xxddrrssttrriinngg(). void xxddrrddeessttrrooyy(XDR *xdrs) A macro that invokes the destroy routine associated with the XDR stream, xdrs. Destruction usually involves freeing private data structures associated with the stream. Using xdrs after invoking xxddrrddeessttrrooyy() is undefined. int xxddrrddoouubbllee(XDR *xdrs, double *dp) A filter primitive that translates between C double precision numbers and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrreennuumm(XDR *xdrs, enumt *ep) A filter primitive that translates between C enums (actually integers) and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrrffllooaatt(XDR *xdrs, float *fp) A filter primitive that translates between C floats and their

external representations. This routine returns one if it suc-

ceeds, zero otherwise. void xxddrrffrreeee(xdrproct proc, char *objp) Generic freeing routine. The first argument is the XDR routine for the object being freed. The second argument is a pointer to the object itself. Note: the pointer passed to this routine is not freed, but what it points to is freed (recursively). uint xxddrrggeettppooss(XDR *xdrs)

A macro that invokes the get-position routine associated with the

XDR stream, xdrs. The routine returns an unsigned integer, which

indicates the position of the XDR byte stream. A desirable fea-

ture of XDR streams is that simple arithmetic works with this number, although the XDR stream instances need not guarantee this. int xxddrrhhyyppeerr(XDR *xdrs, quadt *llp)

A filter primitive that translates between ANSI C long long inte-

gers and their external representations. This routine returns one if it succeeds, zero otherwise. long * xxddrriinnlliinnee(XDR *xdrs, int len)

A macro that invokes the in-line routine associated with the XDR

stream, xdrs. The routine returns a pointer to a contiguous piece of the stream's buffer; len is the byte length of the desired buffer. Note: pointer is cast to long *. Warning: xxddrriinnlliinnee() may return NULL (0) if it cannot allocate a contiguous piece of a buffer. Therefore the behavior may vary among stream instances; it exists for the sake of efficiency. int xxddrriinntt(XDR *xdrs, int *ip) A filter primitive that translates between C integers and their

external representations. This routine returns one if it suc-

ceeds, zero otherwise. int xxddrrlloonngg(XDR *xdrs, long *lp) A filter primitive that translates between C long integers and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrrlloonngglloonnggtt(XDR *xdrs, quadt *llp)

A filter primitive that translates between ANSI C long long inte-

gers and their external representations. This routine returns one if it succeeds, zero otherwise. void xxddrrmmeemmccrreeaattee(XDR *xdrs, char *addr, uint size, enum xdrop op) This routine initializes the XDR stream object pointed to by xdrs. The stream's data is written to, or read from, a chunk of memory at location addr whose length is no more than size bytes long. The op argument determines the direction of the XDR stream (either XDRENCODE, XDRDECODE, or XDRFREE). int xxddrrooppaaqquuee(XDR *xdrs, char *cp, uint cnt) A filter primitive that translates between fixed size opaque data and its external representation. The cp argument is the address of the opaque object, and cnt is its size in bytes. This routine returns one if it succeeds, zero otherwise. int xxddrrppooiinntteerr(XDR *xdrs, char **objpp, uint objsize, xdrproct xdrobj) Like xxddrrrreeffeerreennccee() except that it serializes NULL pointers,

whereas xxddrrrreeffeerreennccee() does not. Thus, xxddrrppooiinntteerr() can repre-

sent recursive data structures, such as binary trees or linked lists. void xxddrrrreeccccrreeaattee(XDR *xdrs, uint sendsize, uint recvsize, char *handle, int (*readit)(), int (*writeit)()) This routine initializes the XDR stream object pointed to by xdrs. The stream's data is written to a buffer of size sendsize; a value of zero indicates the system should use a suitable default. The stream's data is read from a buffer of size recvsize; it too can be set to a suitable default by passing a zero value. When a stream's output buffer is full, wwrriitteeiitt() is called. Similarly, when a stream's input buffer is empty,

rreeaaddiitt() is called. The behavior of these two routines is simi-

lar to the system calls read(2) and write(2), except that handle is passed to the former routines as the first argument. Note: the XDR stream's op field must be set by the caller. Warning: this XDR stream implements an intermediate record stream. Therefore there are additional bytes in the stream to provide record boundary information. int xxddrrrreecceennddooffrreeccoorrdd(XDR *xdrs, int sendnow) This routine can be invoked only on streams created by xxddrrrreeccccrreeaattee(). The data in the output buffer is marked as a completed record, and the output buffer is optionally written out

if sendnow is non-zero. This routine returns one if it succeeds,

zero otherwise. int xxddrrrreecceeooff(XDR *xdrs) This routine can be invoked only on streams created by xxddrrrreeccccrreeaattee(). After consuming the rest of the current record in the stream, this routine returns one if the stream has no more input, zero otherwise. int xxddrrrreeccsskkiipprreeccoorrdd(XDR *xdrs) This routine can be invoked only on streams created by xxddrrrreeccccrreeaattee(). It tells the XDR implementation that the rest

of the current record in the stream's input buffer should be dis-

carded. This routine returns one if it succeeds, zero otherwise. int xxddrrrreeffeerreennccee(XDR *xdrs, char **pp, uint size, xdrproct proc) A primitive that provides pointer chasing within structures. The pp argument is the address of the pointer; size is the ssiizzeeooff the structure that *pp points to; and proc is an XDR procedure that

filters the structure between its C form and its external repre-

sentation. This routine returns one if it succeeds, zero other-

wise. Warning: this routine does not understand NULL pointers. Use xxddrrppooiinntteerr() instead. int xxddrrsseettppooss(XDR *xdrs, uint pos) A macro that invokes the set position routine associated with the XDR stream xdrs. The pos argument is a position value obtained from xxddrrggeettppooss(). This routine returns one if the XDR stream could be repositioned, and zero otherwise. Warning: it is difficult to reposition some types of XDR streams, so this routine may fail with one type of stream and succeed with another. int xxddrrsshhoorrtt(XDR *xdrs, short *sp) A filter primitive that translates between C short integers and their external representations. This routine returns one if it succeeds, zero otherwise.

#ifdef STDIOH

/* XDR using stdio library */ void xxddrrssttddiiooccrreeaattee(XDR *xdrs, FILE *file, enum xdrop op)

#endif

This routine initializes the XDR stream object pointed to by

xdrs. The XDR stream data is written to, or read from, the Stan-

dard I/O stream file. The op argument determines the direction of the XDR stream (either XDRENCODE, XDRDECODE, or XDRFREE). Warning: the destroy routine associated with such XDR streams calls fflush(3) on the file stream, but never fclose(3). int xxddrrssttrriinngg(XDR *xdrs, char **sp, uint maxsize) A filter primitive that translates between C strings and their corresponding external representations. Strings cannot be longer than maxsize. Note: sp is the address of the string's pointer. This routine returns one if it succeeds, zero otherwise. int xxddrruucchhaarr(XDR *xdrs, unsigned char *ucp) A filter primitive that translates between unsigned C characters and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrruuhhyyppeerr(XDR *xdrs, uquadt *ullp) A filter primitive that translates between unsigned ANSI C long long integers and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrruuiinntt(XDR *xdrs, unsigned *up) A filter primitive that translates between C unsigned integers and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrruulloonngg(XDR *xdrs, unsigned long *ulp)

A filter primitive that translates between C unsigned long inte-

gers and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrruulloonngglloonnggtt(XDR *xdrs, uquadt *ullp) A filter primitive that translates between unsigned ANSI C long long integers and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrruusshhoorrtt(XDR *xdrs, unsigned short *usp)

A filter primitive that translates between C unsigned short inte-

gers and their external representations. This routine returns one if it succeeds, zero otherwise. int xxddrruunniioonn(XDR *xdrs, enumt *dscmp, char *unp, const struct xdrdiscrim *choices, xdrproct defaultarm) A filter primitive that translates between a discriminated C union and its corresponding external representation. It first translates the discriminant of the union located at dscmp. This discriminant is always an enumt. Next the union located at unp is translated. The choices argument is a pointer to an array of xdrdiscrim structures. Each structure contains an ordered pair of [value, proc]. If the union's discriminant is equal to the associated value, then the pprroocc() is called to translate the union. The end of the xdrdiscrim structure array is denoted by a routine of value NULL. If the discriminant is not found in the choices array, then the ddeeffaauullttaarrmm() procedure is called (if it is not NULL). Returns one if it succeeds, zero otherwise. int xxddrrvveeccttoorr(XDR *xdrs, char *arrp, uint size, uint elsize, xdrproct elproc)

A filter primitive that translates between fixed-length arrays

and their corresponding external representations. The arrp argu-

ment is the address of the pointer to the array, while size is the element count of the array. The elsize argument is the ssiizzeeooff each of the array's elements, and elproc is an XDR filter that translates between the array elements' C form, and their

external representation. This routine returns one if it suc-

ceeds, zero otherwise. int xxddrrvvooiidd(void)

This routine always returns one. It may be passed to RPC rou-

tines that require a function argument, where nothing is to be done. int xxddrrwwrraappssttrriinngg(XDR *xdrs, char **sp) A primitive that calls xxddrrssttrriinngg(xdrs, sp, MAXUN.UNSIGNED); where MAXUN.UNSIGNED is the maximum value of an unsigned integer. The xxddrrwwrraappssttrriinngg() function is handy because the RPC package passes a maximum of two XDR routines as arguments, and xxddrrssttrriinngg(), one of the most frequently used primitives, requires three. Returns one if it succeeds, zero otherwise.