1erl_global(3)                 C Library Functions                erl_global(3)
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NAME

6       erl_global - Access globally registered names.
7

DESCRIPTION

9       This  module provides support for registering, looking up, and unregis‐
10       tering names in the global  module.  For  more  information,  see  ker‐
11       nel:global.
12
13       Notice  that  the  functions  below  perform  an RPC using an open file
14       descriptor provided by the caller. This file  descriptor  must  not  be
15       used for other traffic during the global operation, as the function can
16       then receive unexpected data and fail.
17

EXPORTS

19       char **erl_global_names(fd,count)
20
21              Types:
22
23                 int fd;
24                 int *count;
25
26              Retrieves a list of all known global names.
27
28                * fd is an open descriptor to an Erlang connection.
29
30                * count is the address of an integer, or NULL. If count is not
31                  NULL,  it  is  set  by  the  function to the number of names
32                  found.
33
34              On success, the function returns an array of strings, each  con‐
35              taining  a  single registered name, and sets count to the number
36              of names found.  The  array  is  terminated  by  a  single  NULL
37              pointer.  On failure, the function returns NULL and count is not
38              modified.
39
40          Note:
41              It is the caller's responsibility to free the array  afterwards.
42              It has been allocated by the function with a single call to mal‐
43              loc(), so a single free() is all that is necessary.
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45
46       int erl_global_register(fd,name,pid)
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48              Types:
49
50                 int fd;
51                 const char *name;
52                 ETERM *pid;
53
54              Registers a name in global.
55
56                * fd is an open descriptor to an Erlang connection.
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58                * name is the name to register in global.
59
60                * pid is the pid that is to  be  associated  with  name.  This
61                  value is returned by global when processes request the loca‐
62                  tion of name.
63
64              Returns 0 on success, otherwise -1.
65
66       int erl_global_unregister(fd,name)
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68              Types:
69
70                 int fd;
71                 const char *name;
72
73              Unregisters a name from global.
74
75                * fd is an open descriptor to an Erlang connection.
76
77                * name is the name to unregister from global.
78
79              Returns 0 on success, otherwise -1.
80
81       ETERM *erl_global_whereis(fd,name,node)
82
83              Types:
84
85                 int fd;
86                 const char *name;
87                 char *node;
88
89              Looks up a name in global.
90
91                * fd is an open descriptor to an Erlang connection.
92
93                * name is the name that is to be looked up in global.
94
95              If node is not NULL, it is a pointer to a buffer where the func‐
96              tion  can fill in the name of the node where name is found. node
97              can be passed directly to erl_connect() if necessary.
98
99              On success, the function returns an Erlang  pid  containing  the
100              address  of  the  specified name, and the node is initialized to
101              the node name where name is found. On failure, NULL is  returned
102              and node is not modified.
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106Ericsson AB                 erl_interface 3.10.2.2               erl_global(3)