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-rw-r--r--erts/doc/src/erl_nif.xml43
1 files changed, 38 insertions, 5 deletions
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml
index b31052287d..b0a632d2d6 100644
--- a/erts/doc/src/erl_nif.xml
+++ b/erts/doc/src/erl_nif.xml
@@ -675,6 +675,18 @@ typedef struct {
<p>When receiving data from untrusted sources, use option
<c>ERL_NIF_BIN2TERM_SAFE</c>.</p>
</item>
+ <tag><marker id="ErlNifMonitor"/><c>ErlNifMonitor</c></tag>
+ <item>
+ <p>This is an opaque data type that identifies a monitor.</p>
+ <p>The nif writer is to provide the memory for storing the
+ monitor when calling <seealso marker="#enif_monitor_process">
+ <c>enif_monitor_process</c></seealso>. The
+ address of the data is not stored by the runtime system, so
+ <c>ErlNifMonitor</c> can be used as any other data, it
+ can be copied, moved in memory, forgotten, and so on.
+ To compare two monitors, <seealso marker="#enif_compare_monitors">
+ <c>enif_compare_monitors</c></seealso> must be used.</p>
+ </item>
<tag><marker id="ErlNifPid"/><c>ErlNifPid</c></tag>
<item>
<p>A process identifier (pid). In contrast to pid terms (instances of
@@ -910,6 +922,21 @@ typedef enum {
</func>
<func>
+ <name><ret>int</ret><nametext>enif_compare_monitors(const ErlNifMonitor
+ *monitor1, const ErlNifMonitor *monitor2)</nametext></name>
+ <fsummary>Compare two monitors.</fsummary>
+ <desc>
+ <marker id="enif_compare_monitors"></marker>
+ <p>Compares two <seealso marker="#ErlNifMonitor"><c>ErlNifMonitor</c></seealso>s.
+ Can also be used to imply some artificial order on monitors,
+ for whatever reason.</p>
+ <p>Returns <c>0</c> if <c>monitor1</c> and <c>monitor2</c> are equal,
+ &lt; <c>0</c> if <c>monitor1</c> &lt; <c>monitor2</c>, and
+ &gt; <c>0</c> if <c>monitor1</c> &gt; <c>monitor2</c>.</p>
+ </desc>
+ </func>
+
+ <func>
<name><ret>void</ret>
<nametext>enif_cond_broadcast(ErlNifCond *cnd)</nametext></name>
<fsummary></fsummary>
@@ -1042,7 +1069,7 @@ typedef enum {
<fsummary>Cancel a process monitor.</fsummary>
<desc>
<marker id="enif_demonitor_process"></marker>
- <p>Cancels a monitor created earlier with <seealso marker="enif_monitor_process">
+ <p>Cancels a monitor created earlier with <seealso marker="#enif_monitor_process">
<c>enif_monitor_process</c></seealso>. Argument <c>obj</c> is a pointer
to the resource holding the monitor and <c>*mon</c> identifies the monitor.</p>
<p>Returns <c>0</c> if the monitor was successfully identified and removed.
@@ -1050,6 +1077,7 @@ typedef enum {
it was either</p>
<list type="bulleted">
<item>never created for this resource</item>
+ <item>already cancelled</item>
<item>already triggered</item>
<item>just about to be triggered by a concurrent thread</item>
</list>
@@ -2182,14 +2210,19 @@ enif_map_iterator_destroy(env, &amp;iter);</code>
<marker id="enif_monitor_process"></marker>
<p>Starts monitoring a process from a resource. When a process is
monitored, a process exit results in a call to the provided
- <seealso marker="ErlNifResourceDown">
+ <seealso marker="#ErlNifResourceDown">
<c>down</c></seealso> callback associated with the resource type.</p>
<p>Argument <c>obj</c> is pointer to the resource to hold the monitor and
<c>*target_pid</c> identifies the local process to be monitored.</p>
<p>If <c>mon</c> is not <c>NULL</c>, a successful call stores the
- identity of the monitor in the struct pointed to by <c>mon</c>.
- This identifier is used to refer to the monitor for later removal or
- compare. A monitor is automatically removed when it triggers or when
+ identity of the monitor in the
+ <seealso marker="#ErlNifMonitor"><c>ErlNifMonitor</c></seealso>
+ struct pointed to by <c>mon</c>. This identifier is used to refer to the
+ monitor for later removal with
+ <seealso marker="#enif_demonitor_process"><c>enif_demonitor_process</c></seealso>
+ or compare with
+ <seealso marker="#enif_compare_monitors"><c>enif_compare_monitors</c></seealso>.
+ A monitor is automatically removed when it triggers or when
the resource is deallocated.</p>
<p>Returns <c>0</c> on success, &lt; 0 if no <c>down</c> callback is
provided, and &gt; 0 if the process is no longer alive.</p>