From 9197f6ea9af095eebbbf42e4ceca5ef762467276 Mon Sep 17 00:00:00 2001
From: Sverker Eriksson
Date: Wed, 20 Feb 2019 16:04:58 +0100
Subject: erts: Add enif_set_pid_undefined & enif_is_pid_undefined
---
erts/doc/src/erl_nif.xml | 42 +++++++++++++++++++++++++++++++++++++-----
1 file changed, 37 insertions(+), 5 deletions(-)
(limited to 'erts/doc')
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml
index d58ebd3171..ac873d0c8c 100644
--- a/erts/doc/src/erl_nif.xml
+++ b/erts/doc/src/erl_nif.xml
@@ -783,14 +783,16 @@ typedef struct {
A process identifier (pid). In contrast to pid terms (instances of
ERL_NIF_TERM), ErlNifPids are self-contained and not
bound to any environment.
- ErlNifPid is an opaque type.
+ ErlNifPid is an opaque type. It can be copied, moved
+ in memory, forgotten, and so on.
ErlNifPort
-
A port identifier. In contrast to port ID terms (instances of
ERL_NIF_TERM), ErlNifPorts are self-contained and not
bound to any environment.
- ErlNifPort is an opaque type.
+ ErlNifPort is an opaque type. It can be copied, moved
+ in memory, forgotten, and so on.
ErlNifResourceType
-
@@ -1392,6 +1394,9 @@ enif_free_iovec(iovec);]]>
initializes the pid variable *pid from it and returns
true. Otherwise returns false. No check is done to see
if the process is alive.
+
enif_get_local_pid will return false if argument
+ term is the atom
+ undefined.
@@ -1870,6 +1875,17 @@ enif_inspect_iovec(env, max_elements, term, &tail, &iovec);
+
+ int
+ enif_is_pid_undefined(const ErlNifPid* pid)
+ Determine if pid is undefined.
+
+ Returns true if pid has been set as undefined by
+ enif_set_pid_undefined
+ .
+
+
+
int
enif_is_port(ErlNifEnv* env, ERL_NIF_TERM term)
@@ -2259,7 +2275,8 @@ enif_inspect_iovec(env, max_elements, term, &tail, &iovec);
Make a pid term.
- Makes a pid term from *pid.
+ Makes a pid term or the atom
+ undefined from *pid.
@@ -2625,7 +2642,9 @@ enif_map_iterator_destroy(env, &iter);
Argument caller_env is the environment of the calling process
or callback. Must only be NULL if calling from a custom thread.
Returns 0 on success, < 0 if no down callback is
- provided, and > 0 if the process is no longer alive.
+ provided, and > 0 if the process is no longer alive or if
+ target_pid is
+ undefined.
This function is only thread-safe when the emulator with SMP support
is used. It can only be used in a non-SMP emulator from a NIF-calling
thread.
@@ -3080,7 +3099,9 @@ enif_map_iterator_destroy(env, &iter);
enif_select_write
introduced in erts-11.0 (OTP-22.0).
- Argument pid may be NULL to indicate the calling process.
+ Argument pid may be NULL to indicate the calling
+ process. It must not be set as
+ undefined.
Argument obj is a resource object obtained from
enif_alloc_resource.
The purpose of the resource objects is as a container of the event object
@@ -3270,6 +3291,17 @@ if (retval & ERL_NIF_SELECT_STOP_CALLED) {
+
+ void
+ enif_set_pid_undefined(ErlNifPid* pid)
+ Set pid as undefined.
+
+ Sets an ErlNifPid
+ variable as undefined. See
+ enif_is_pid_undefined.
+
+
+
unsigned
enif_sizeof_resource(void* obj)
--
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