diff options
Diffstat (limited to 'erts/doc/src/erl_nif.xml')
| -rw-r--r-- | erts/doc/src/erl_nif.xml | 67 |
1 files changed, 65 insertions, 2 deletions
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index 8cdfc80879..bd72bdb691 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -711,6 +711,21 @@ typedef struct { <code type="none"> typedef void ErlNifResourceDtor(ErlNifEnv* env, void* obj);</code> <p>The function prototype of a resource destructor function.</p> + <p>The <c>obj</c> argument is a pointer to the resource. The only + allowed use for the resource in the destructor is to access its + user data one final time. The destructor is guaranteed to be the + last callback before the resource is deallocated.</p> + </item> + <tag><marker id="ErlNifResourceDown"/><c>ErlNifResourceDown</c></tag> + <item> + <code type="none"> +typedef void ErlNifResourceDown(ErlNifEnv* env, void* obj, const ErlNifPid* pid, const ErlNifMonitor* mon);</code> + <p>The function prototype of a resource down function, + called on the behalf of <seealso marker="#enif_monitor_process"> + enif_monitor_process</seealso>. <c>obj</c> is the resource, <c>pid</c> + is the identity of the monitored process that is exiting, and <c>mon</c> + is the identity of the monitor. + </p> </item> <tag><marker id="ErlNifResourceStop"/><c>ErlNifResourceStop</c></tag> <item> @@ -1022,6 +1037,29 @@ typedef enum { </func> <func> + <name><ret>int</ret><nametext>enif_demonitor_process(ErlNifEnv* env, void* obj, + const ErlNifMonitor* mon)</nametext></name> + <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"> + <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. + Returns a non-zero value if the monitor could not be identified, which means + it was either</p> + <list type="bulleted"> + <item>never created for this resource</item> + <item>already triggered</item> + <item>just about to be triggered by a concurrent thread</item> + </list> + <p>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.</p> + </desc> + </func> + + <func> <name><ret>int</ret> <nametext>enif_equal_tids(ErlNifTid tid1, ErlNifTid tid2)</nametext> </name> @@ -2137,6 +2175,31 @@ enif_map_iterator_destroy(env, &iter);</code> </func> <func> + <name><ret>int</ret><nametext>enif_monitor_process(ErlNifEnv* env, void* obj, + const ErlNifPid* target_pid, ErlNifMonitor* mon)</nametext></name> + <fsummary>Monitor a process from a resource.</fsummary> + <desc> + <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"> + <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 + the resource is deallocated.</p> + <p>Returns <c>0</c> on success, < 0 if no <c>down</c> callback is + provided, and > 0 if the process is no longer alive.</p> + <p>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.</p> + </desc> + </func> + + <func> <name><ret>ErlNifTime</ret> <nametext>enif_monotonic_time(ErlNifTimeUnit time_unit)</nametext> </name> @@ -2268,8 +2331,8 @@ enif_map_iterator_destroy(env, &iter);</code> used together with <seealso marker="#enif_select"><c>enif_select</c></seealso>.</p> <p>Argument <c>init</c> is a pointer to an <seealso marker="#ErlNifResourceTypeInit"><c>ErlNifResourceTypeInit</c></seealso> - structure that contains the function pointers for the destructor and the stop callback - of the resource type.</p> + structure that contains the function pointers for destructor, down and stop callbacks + for the resource type.</p> </desc> </func> |