xdr_create(3N)xdr_create(3N)NAME
xdr_create, xdr_destroy, xdrmem_create, xdrrec_create, xdrstdio_create
- library routines for external data representation stream creation
SYNOPSISDESCRIPTION
XDR library routines allow C programmers to describe arbitrary data
structures in a machine-independent fashion. Protocols such as remote
procedure calls (RPC) use these routines to describe the format of the
data.
These routines deal with the creation of XDR streams. XDR streams have
to be created before any data can be translated into XDR format.
Routines
See rpc(3N) for the definition of the and data structures. Any buffers
passed to the XDR routines must be properly aligned. It is suggested
either that malloc(3C) be used to allocate these buffers or that the
programmer insure that the buffer address is divisible evenly by four.
A macro that invokes the destroy routine associated with the
XDR stream, xdrs. Private data structures associated with the
stream are freed. Using xdrs after invoking is undefined.
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 less than size bytes
long. The parameter op determines the direction of the XDR
stream. The value of op can be either or In the case where the
value of size exceeds resets size to
This routine initializes the read-oriented XDR
stream object pointed to by xdrs. The stream's data is written
to a buffer of size sendsz; a value of indicates the system
should use a suitable default. The stream's data is read from a
buffer of size recvsz; it too can be set to a suitable default
by passing a value. When a stream's output buffer is full,
writeit is called. Similarly, when a stream's input buffer is
empty, readit is called. The behavior of these two routines is
similar to the system calls and (see read(2) and write(2),
respectively), except that an appropriate handle (read_handle or
write_handle) is passed to the former routines as the first
parameter instead of a file descriptor. 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.
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 parameter op determines the direction
of the XDR stream. The value of op can be either or
Warning: the destroy routine associated with such XDR streams
calls on the file stream, but never (see fclose(3S)).
Failure of the function can be detected by first initializing the x_ops
field in the structure to NULL before calling the function. After the
return from the function, if the x_ops field is still NULL, the call
has failed. If the x_ops field contains some other value, assume the
call has succeeded. Failures cannot be detected for the and functions.
MULTITHREAD USAGE
Thread Safe: Yes
Cancel Safe: Yes
Fork Safe: No
Async-cancel Safe: No
Async-signal Safe: No
These functions can be called safely in a multithreaded environment.
They may be cancellation points in that they call functions that are
cancel points.
In a multithreaded environment, these functions are not safe to be
called by a child process after and before These functions should not
be called by a multithreaded application that supports asynchronous
cancellation or asynchronous signals.
SEE ALSOread(2), write(2), fclose(3S), malloc(3C), rpc(3N), xdr_admin(3N),
xdr_complex(3N), xdr_simple(3N).
xdr_create(3N)
