PTREE_REGISTER_HANDLER(3PICLTREE)PTREE_REGISTER_HANDLER(3PICLTREE)NAMEptree_register_handler - register a handler for the event
SYNOPSIS
cc [ flag... ] file... -lpicltree [ library... ]
#include <picltree.h>
int ptree_register_handler(const char *ename,
void (*evt_handler)(const char *ename, const void *earg,
size_t size, void *cookie), void *cookie);
DESCRIPTION
The ptree_register_handler() function registers an event handler for a
PICL event. The argument ename specifies the name of the PICL event for
which to register the handler. The argument evt_handler specifies the
event handler function. The argument cookie is a pointer to caller-spe‐
cific data to be passed as an argument to the event handler when it is
invoked.
The event handler function must be defined as
void evt_handler(const char *ename, const void *earg, \
size_t size, void *cookie)
where, ename, earg, size, and cookie are the arguments passed to the
event handler when it is invoked. The argument ename is the PICL event
name for which the handler is invoked. The arguments earg and size
gives the pointer to the event argument buffer and its size, respec‐
tively. The argument cookie is the pointer to the caller specific data
registered with the handler. The arguments ename and earg point to buf‐
fers that are transient and shall not be modified by the event handler
or reused after the event handler finishes execution.
The PICL framework invokes the event handlers in the order in which
they were registered when dispatching an event. If the event handler
execution order is required to be the same as the plug-in dependency
order, then a plug-in should register its handlers from its init func‐
tion. The handlers that do not have any ordering dependencies on other
plug-in handlers can be registered at any time.
The registered handler may be called at any time after this function is
called.
RETURN VALUES
Upon successful completion, 0 is returned. On failure, a non-negative
integer is returned to indicate an error and the handler is not regis‐
tered.
ERRORS
PICL_INVALIDARG
Invalid argument
PICL_FAILURE
General system failure
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────┬─────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────┼─────────────────┤
│Interface Stability │ Evolving │
├────────────────────┼─────────────────┤
│MT-Level │ MT-Safe │
└────────────────────┴─────────────────┘
SEE ALSOptree_unregister_handler(3PICLTREE), attributes(5)
Aug 1, 2000PTREE_REGISTER_HANDLER(3PICLTREE)
