erl_global
This module provides support for registering, looking up and unregistering names in the Erlang Global module. For more information, see the description of Global in the reference manual.
Note that the functions below perform an RPC using an open file descriptor provided by the caller. This file descriptor must not be used for other traffic during the global operation or the function may receive unexpected data and fail.
Functions
int fd;
int *count;
Retrieve a list of all known global names.
fd
is an open descriptor to an Erlang connection.
count
is the address of an integer, or NULL. If
count
is not NULL, it will be set by the function to
the number of names found.
On success, the function returns an array of strings, each
containing a single registered name, and sets count
to
the number of names found. The array is terminated
by a single NULL pointer. On failure, the function returns
NULL and count
is not modified.
Note!
It is the caller's responsibility to free the array
afterwards. It has been allocated by the function with a
single call to malloc()
, so a single free()
is
all that is necessary.
int fd;
const char *name;
ETERM *pid;
This function registers a name in Global.
fd
is an open descriptor to an Erlang connection.
name
is the name to register in Global.
pid
is the pid that should be associated with
name
. This is the value that Global will return when
processes request the location of name
.
The function returns 0 on success, or -1 on failure.
int fd;
const char *name;
This function unregisters a name from Global.
fd
is an open descriptor to an Erlang connection.
name
is the name to unregister from Global.
The function returns 0 on success, or -1 on failure.
int fd;
const char *name;
char *node;
fd
is an open descriptor to an Erlang connection.
name
is the name that is to be looked up in Global.
If node
is not NULL, it is a pointer to a buffer
where the function can fill in the name of the node where
name
is found. node
can be passed directly to
erl_connect()
if necessary.
On success, the function returns an Erlang Pid containing the address
of the given name, and node will be initialized to
the nodename where name
is found. On failure NULL will be
returned and node
will not be modified.