DC_PLUG_NEW(2) distcache DC_PLUG_NEW(2)NAME
DC_PLUG_new, DC_PLUG_free, DC_PLUG_to_select, DC_PLUG_io - basic
DC_PLUG functions
SYNOPSIS
#include <distcache/dc_plug.h>
DC_PLUG *DC_PLUG_new(NAL_CONNECTION *conn, unsigned int flags);
int DC_PLUG_free(DC_PLUG *plug);
void DC_PLUG_to_select(DC_PLUG *plug, NAL_SELECTOR *sel);
int DC_PLUG_io(DC_PLUG *plug, NAL_SELECTOR *sel);
DESCRIPTIONDC_PLUG_new() allocates and initialises a DC_PLUG structure encapsulat‐
ing the specified connection. The flags parameter is zero or a bitmask
combining one or more of the following flags;
#define DC_PLUG_FLAG_TO_SERVER (unsigned int)0x0001
#define DC_PLUG_FLAG_NOFREE_CONN (unsigned int)0x0002
If the DC_PLUG_FLAG_TO_SERVER flag is specified, the plug object will
expect to be sending ``request'' messages and receiving ``response''
messages, otherwise will default to the opposite sense.
DC_PLUG_free() frees the DC_PLUG structure and, unless it had been cre‐
ated with the DC_PLUG_FLAG_NOFREE_CONN flag, will also destroy the con‐
nection object it encapsulates.
DC_PLUG_to_select() is used to add a plug object to the sel selector so
that it can be tested for network events it is waiting on. This will
automatically handle selection of flags depending on the plug object's
state. Ie. it will select for writability on its underlying connection
only if there is data waiting to be sent, and likewise will select for
readability only if it is ready to receive any data that may have
arrived.
DC_PLUG_io() is used to allow network I/O to be performed on a plug
object's underlying connection depending on the results of the last
select operation on sel.
RETURN VALUESDC_PLUG_new() returns the new plug object on success, otherwise NULL
for failure.
DC_PLUG_free() should never fail and should only return non-zero
results.
DC_PLUG_to_select() has no return value.
DC_PLUG_io() return zero on an error, otherwise non-zero.
None of the DC_PLUG functions sets (or clears) errno because it is
implemented on top of the libnal library which in turn is an abstrac‐
tion layer for the system's networking interfaces. As such, any errno
codes set by failure in system libraries will not be overwritten by
these functions.
SEE ALSODC_PLUG_read(2) - Provides documentation for other DC_PLUG functions
also.
distcache(8) - Overview of the distcache architecture.
http://www.distcache.org/ - Distcache home page.
AUTHOR
This toolkit was designed and implemented by Geoff Thorpe for Crypto‐
graphic Appliances Incorporated. Since the project was released into
open source, it has a home page and a project environment where devel‐
opment, mailing lists, and releases are organised. For problems with
the software or this man page please check for new releases at the
project web-site below, mail the users mailing list described there, or
contact the author at geoff@geoffthorpe.net.
Home Page: http://www.distcache.org
1.4.5 2004.03.23 DC_PLUG_NEW(2)
