ei_global(3erl) C Library Functions ei_global(3erl)
NAME
ei_global - Access globally registered names.
DESCRIPTION
This module provides support for registering, looking up, and unregis-
tering names in the global module. For more information, see ker-
nel:global.
Notice that the functions below perform an RPC using an open file de-
scriptor provided by the caller. This file descriptor must not be used
for other traffic during the global operation, as the function can then
receive unexpected data and fail.
EXPORTS
char **ei_global_names(ec,fd,count)
Types:
ei_cnode *ec;
int fd;
int *count;
Retrieves a list of all known global names.
* ec is the ei_cnode representing the current cnode.
* fd is an open descriptor to an Erlang connection.
* count is the address of an integer, or NULL. If count is not
NULL, it is set by the function to the number of names
found.
On success, the function returns an array of strings, each con-
taining 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 mal-
loc(), so a single free() is all that is necessary.
int ei_global_register(fd,name,pid)
Types:
int fd;
const char *name;
erlang_pid *pid;
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 is to be associated with name. This
value is returned by global when processes request the loca-
tion of name.
Returns 0 on success, otherwise -1.
int ei_global_unregister(ec,fd,name)
Types:
ei_cnode *ec;
int fd;
const char *name;
Unregisters a name from global.
* ec is the ei_cnode representing the current cnode.
* fd is an open descriptor to an Erlang connection.
* name is the name to unregister from global.
Returns 0 on success, otherwise -1.
int ei_global_whereis(ec,fd,name,pid,node)
Types:
ei_cnode *ec;
int fd;
const char *name;
erlang_pid *pid;
char *node;
Looks up a name in global.
* ec is the ei_cnode representing the current cnode.
* fd is an open descriptor to an Erlang connection.
* name is the name that is to be looked up in global.
The pid parameter is a pointer to a erlang_pid that the function
will update with the pid associated with the global name, if
successful.
If node is not NULL, it is a pointer to a buffer where the func-
tion can fill in the name of the node where name is found. node
can be passed directly to ei_connect() if necessary.
On success, the function returns 0, updates the erlang_pid
pointed to by the pid parameter, and the node parameter is ini-
tialized to the node name where name is found. On failure, a
negative number is returned.
Ericsson AB erl_interface 4.0 ei_global(3erl)