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-rw-r--r--lib/stdlib/doc/src/dets.xml31
-rw-r--r--lib/stdlib/doc/src/erl_parse.xml120
-rw-r--r--lib/stdlib/doc/src/erl_scan.xml185
-rw-r--r--lib/stdlib/doc/src/ets.xml41
-rw-r--r--lib/stdlib/doc/src/supervisor.xml5
5 files changed, 145 insertions, 237 deletions
diff --git a/lib/stdlib/doc/src/dets.xml b/lib/stdlib/doc/src/dets.xml
index a0d3f95b6a..48400733d1 100644
--- a/lib/stdlib/doc/src/dets.xml
+++ b/lib/stdlib/doc/src/dets.xml
@@ -399,15 +399,40 @@
kept in RAM.</p>
</item>
<item>
- <p><c>{safe_fixed,</c> SafeFixed<c>}</c>. If the table
- is fixed, SafeFixed is a tuple <c>{FixedAtTime, [{Pid,RefCount}]}</c>. <c>FixedAtTime</c> is the time when
+ <p><c>{safe_fixed_monotonic_time, SafeFixed}</c>. If the table
+ is fixed, <c>SafeFixed</c> is a tuple <c>{FixedAtTime, [{Pid,RefCount}]}</c>.
+ <c>FixedAtTime</c> is the time when
the table was first fixed, and <c>Pid</c> is the pid of
the process that fixes the table <c>RefCount</c> times.
There may be any number of processes in the list. If the
table is not fixed, SafeFixed is the atom <c>false</c>.</p>
+ <p><c>FixedAtTime</c> will correspond to the result
+ returned by
+ <seealso marker="erts:erlang#monotonic_time/0">erlang:monotonic_time/0</seealso>
+ at the time of fixation. The usage of <c>safe_fixed_monotonic_time</c> is
+ <seealso marker="erts:time_correction#Time_Warp_Safe_Code">time warp
+ safe</seealso>.</p>
</item>
<item>
- <p><c>{version, integer()</c>, the version of the format of
+ <p>
+ <c>{safe_fixed, SafeFixed}</c>. The same as
+ <c>{safe_fixed_monotonic_time, SafeFixed}</c> with the exception
+ of the format and value of <c>FixedAtTime</c>.
+ </p>
+ <p>
+ <c>FixedAtTime</c> will correspond to the result returned by
+ <seealso marker="erts:erlang#timestamp/0">erlang:timestamp/0</seealso>
+ at the time of fixation. Note that when the system is using
+ single or multi
+ <seealso marker="erts:time_correction#Time_Warp_Modes">time warp
+ modes</seealso> this might produce strange results. This
+ since the usage of <c>safe_fixed</c> is not
+ <seealso marker="erts:time_correction#Time_Warp_Safe_Code">time warp
+ safe</seealso>. Time warp safe code need to use
+ <c>safe_fixed_monotonic_time</c> instead.</p>
+ </item>
+ <item>
+ <p><c>{version, integer()}</c>, the version of the format of
the table.</p>
</item>
</list>
diff --git a/lib/stdlib/doc/src/erl_parse.xml b/lib/stdlib/doc/src/erl_parse.xml
index 0938b5dec3..13be488c33 100644
--- a/lib/stdlib/doc/src/erl_parse.xml
+++ b/lib/stdlib/doc/src/erl_parse.xml
@@ -4,7 +4,7 @@
<erlref>
<header>
<copyright>
- <year>1996</year><year>2015</year>
+ <year>1996</year><year>2016</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -44,21 +44,33 @@
</description>
<datatypes>
<datatype>
- <name name="abstract_clause"></name>
- <desc><p>Parse tree for Erlang clause.</p>
+ <name>abstract_clause()</name>
+ <desc><p><marker id="type-abstract_clause"/>
+ Abstract form of an Erlang clause.</p>
</desc>
</datatype>
<datatype>
- <name name="abstract_expr"></name>
- <desc><p>Parse tree for Erlang expression.</p>
+ <name>abstract_expr()</name>
+ <desc><p><marker id="type-abstract_expr"/>
+ Abstract form of an Erlang expression.</p>
</desc>
</datatype>
<datatype>
- <name name="abstract_form"></name>
- <desc><p>Parse tree for Erlang form.</p>
+ <name>abstract_form()</name>
+ <desc><p><marker id="type-abstract_form"/>
+ Abstract form of an Erlang form.</p>
</desc>
</datatype>
<datatype>
+ <name>abstract_type()</name>
+ <desc><p><marker id="type-abstract_type"/>
+ Abstract form of an Erlang type.</p>
+ </desc>
+ </datatype>
+ <datatype>
+ <name name="erl_parse_tree"></name>
+ </datatype>
+ <datatype>
<name name="error_description"></name>
</datatype>
<datatype>
@@ -180,7 +192,7 @@
<p>Converts the Erlang data structure <c><anno>Data</anno></c> into an
abstract form of type <c><anno>AbsTerm</anno></c>.</p>
<p>The <c><anno>Line</anno></c> option is the line that will
- be assigned to each node of the abstract form.</p>
+ be assigned to each node of <c><anno>AbsTerm</anno></c>.</p>
<p>The <c><anno>Encoding</anno></c> option is used for
selecting which integer lists will be considered
as strings. The default is to use the encoding returned by
@@ -196,47 +208,53 @@
<func>
<name name="map_anno" arity="2"/>
<fsummary>
- Map a function over the annotations of an abstract form
+ Map a function over the annotations of a <c>erl_parse</c> tree
</fsummary>
<desc>
- <p>Modifies the abstract form <anno>Abstr</anno> by applying
- <anno>Fun</anno> on every collection of annotations of the
- abstract form. The abstract form is traversed in a
- depth-first, left-to-right, fashion.
+ <p>Modifies the <c>erl_parse</c> tree <c><anno>Abstr</anno></c>
+ by applying <c><anno>Fun</anno></c> on each collection of
+ annotations of the nodes of the <c>erl_parse</c> tree. The
+ <c>erl_parse</c> tree is traversed in a depth-first,
+ left-to-right, fashion.
</p>
</desc>
</func>
<func>
<name name="fold_anno" arity="3"/>
<fsummary>
- Fold a function over the annotations of an abstract form
+ Fold a function over the annotations of a <c>erl_parse</c> tree
</fsummary>
<desc>
- <p>Updates an accumulator by applying <anno>Fun</anno> on
- every collection of annotations of the abstract form
- <anno>Abstr</anno>. The first call to <anno>Fun</anno> has
- <anno>AccIn</anno> as argument, and the returned accumulator
- <anno>AccOut</anno> is passed to the next call, and so on.
- The final value of the accumulator is returned. The abstract
- form is traversed in a depth-first, left-to-right, fashion.
+ <p>Updates an accumulator by applying <c><anno>Fun</anno></c> on
+ each collection of annotations of the <c>erl_parse</c> tree
+ <c><anno>Abstr</anno></c>. The first call to
+ <c><anno>Fun</anno></c> has <c><anno>AccIn</anno></c> as
+ argument, and the returned accumulator
+ <c><anno>AccOut</anno></c> is passed to the next call, and
+ so on. The final value of the accumulator is returned. The
+ <c>erl_parse</c> tree is traversed in a depth-first, left-to-right,
+ fashion.
</p>
</desc>
</func>
<func>
<name name="mapfold_anno" arity="3"/>
<fsummary>
- Map and fold a function over the annotations of an abstract form
+ Map and fold a function over the annotations of a
+ <c>erl_parse</c> tree
</fsummary>
<desc>
- <p>Modifies the abstract form <anno>Abstr</anno> by applying
- <anno>Fun</anno> on every collection of annotations of the
- abstract form, while at the same time updating an
- accumulator. The first call to <anno>Fun</anno> has
- <anno>AccIn</anno> as second argument, and the returned
- accumulator <anno>AccOut</anno> is passed to the next call,
- and so on. The modified abstract form as well as the the
- final value of the accumulator is returned. The abstract
- form is traversed in a depth-first, left-to-right, fashion.
+ <p>Modifies the <c>erl_parse</c> tree <c><anno>Abstr</anno></c>
+ by applying <c><anno>Fun</anno></c> on each collection of
+ annotations of the nodes of the <c>erl_parse</c> tree, while
+ at the same time updating an accumulator. The first call to
+ <c><anno>Fun</anno></c> has <c><anno>AccIn</anno></c> as
+ second argument, and the returned accumulator
+ <c><anno>AccOut</anno></c> is passed to the next call, and
+ so on. The modified <c>erl_parse</c> tree as well as the the
+ final value of the accumulator are returned. The
+ <c>erl_parse</c> tree is traversed in a depth-first,
+ left-to-right, fashion.
</p>
</desc>
</func>
@@ -246,12 +264,15 @@
Create new annotations
</fsummary>
<desc>
- <p>Creates an abstract form from a term which has the same
- structure as an abstract form, but <seealso
- marker="erl_anno#type-location">locations</seealso> where the
- abstract form has annotations. For each location, <seealso
- marker="erl_anno#new/1"><c>erl_anno:new/1</c></seealso> is
- called, and the annotations replace the location.
+ <p>Assumes that <c><anno>Term</anno></c> is a term with the same
+ structure as a <c>erl_parse</c> tree, but with <seealso
+ marker="erl_anno#type-location">locations</seealso> where a
+ <c>erl_parse</c> tree has collections of annotations.
+ Returns a <c>erl_parse</c> tree where each location <c>L</c>
+ has been replaced by the value returned by <seealso
+ marker="erl_anno#new/1"><c>erl_anno:new(L)</c></seealso>.
+ The term <c><anno>Term</anno></c> is traversed in a
+ depth-first, left-to-right, fashion.
</p>
</desc>
</func>
@@ -261,12 +282,14 @@
Return annotations as terms
</fsummary>
<desc>
- <p>Assumes that <anno>Term</anno> is a term with the same
- structure as an abstract form, but with terms, T say, on
- those places where an abstract form has annotations. Returns
- an abstract form where every term T has been replaced by the
- value returned by calling <c>erl_anno:from_term(T)</c>. The
- term <anno>Term</anno> is traversed in a depth-first,
+ <p>Assumes that <c><anno>Term</anno></c> is a term with the same
+ structure as a <c>erl_parse</c> tree, but with terms,
+ <c>T</c> say, where a <c>erl_parse</c> tree has collections
+ of annotations. Returns a <c>erl_parse</c> tree where each
+ term <c>T</c> has been replaced by the value returned by
+ <seealso marker="erl_anno#from_term/1">
+ <c>erl_anno:from_term(T)</c></seealso>. The term
+ <c><anno>Term</anno></c> is traversed in a depth-first,
left-to-right, fashion.
</p>
</desc>
@@ -277,10 +300,13 @@
Return the representation of annotations
</fsummary>
<desc>
- <p>Returns a term where every collection of annotations Anno of
- <anno>Abstr</anno> has been replaced by the term returned by
- calling <c>erl_anno:to_term(Anno)</c>. The abstract form is
- traversed in a depth-first, left-to-right, fashion.
+ <p>Returns a term where each collection of annotations
+ <c>Anno</c> of the nodes of the <c>erl_parse</c> tree
+ <c><anno>Abstr</anno></c> has been replaced by the term
+ returned by <seealso marker="erl_anno#to_term/1">
+ <c>erl_anno:to_term(Anno)</c></seealso>. The
+ <c>erl_parse</c> tree is traversed in a depth-first,
+ left-to-right, fashion.
</p>
</desc>
</func>
diff --git a/lib/stdlib/doc/src/erl_scan.xml b/lib/stdlib/doc/src/erl_scan.xml
index 342f491dd0..ee0d6b6033 100644
--- a/lib/stdlib/doc/src/erl_scan.xml
+++ b/lib/stdlib/doc/src/erl_scan.xml
@@ -40,39 +40,15 @@
</description>
<datatypes>
<datatype>
- <name name="attribute_info"></name>
- </datatype>
- <datatype>
- <name name="attributes"></name>
- </datatype>
- <datatype>
- <name name="attributes_data"></name>
- </datatype>
- <datatype>
<name name="category"></name>
</datatype>
<datatype>
- <name name="column"></name>
- </datatype>
- <datatype>
<name name="error_description"></name>
</datatype>
<datatype>
<name name="error_info"></name>
</datatype>
<datatype>
- <name name="info_line"></name>
- </datatype>
- <datatype>
- <name name="info_location"></name>
- </datatype>
- <datatype>
- <name name="line"></name>
- </datatype>
- <datatype>
- <name name="location"></name>
- </datatype>
- <datatype>
<name name="option"></name>
</datatype>
<datatype>
@@ -88,9 +64,6 @@
<name name="token"></name>
</datatype>
<datatype>
- <name name="token_info"></name>
- </datatype>
- <datatype>
<name name="tokens"></name>
</datatype>
<datatype>
@@ -122,25 +95,23 @@
<anno>StartLocation</anno>, [])</c>.</p>
<p><c><anno>StartLocation</anno></c> indicates the initial location
when scanning starts. If <c><anno>StartLocation</anno></c> is a line,
- <c>attributes()</c> as well as <c><anno>EndLocation</anno></c> and
+ <c>Anno</c> as well as <c><anno>EndLocation</anno></c> and
<c><anno>ErrorLocation</anno></c> will be lines. If
<c><anno>StartLocation</anno></c> is a pair of a line and a column
- <c>attributes()</c> takes the form of an opaque compound
+ <c>Anno</c> takes the form of an opaque compound
data type, and <c><anno>EndLocation</anno></c> and
<c><anno>ErrorLocation</anno></c>
will be pairs of a line and a column. The <em>token
- attributes</em> contain information about the column and the
+ annotations</em> contain information about the column and the
line where the token begins, as well as the text of the
token (if the <c>text</c> option is given), all of which can
- be accessed by calling <seealso
- marker="#token_info/1">token_info/1,2</seealso>, <seealso
- marker="#attributes_info/1">attributes_info/1,2</seealso>,
+ be accessed by calling
<seealso marker="#column/1">column/1</seealso>,
<seealso marker="#line/1">line/1</seealso>,
<seealso marker="#location/1">location/1</seealso>, and
<seealso marker="#text/1">text/1</seealso>.</p>
<p>A <em>token</em> is a tuple containing information about
- syntactic category, the token attributes, and the actual
+ syntactic category, the token annotations, and the actual
terminal symbol. For punctuation characters (e.g. <c>;</c>,
<c>|</c>) and reserved words, the category and the symbol
coincide, and the token is represented by a two-tuple.
@@ -172,7 +143,7 @@
<item><p>Short for <c>[return_comments, return_white_spaces]</c>.</p>
</item>
<tag><c>text</c></tag>
- <item><p>Include the token's text in the token attributes. The
+ <item><p>Include the token's text in the token annotation. The
text is the part of the input corresponding to the token.</p>
</item>
</taglist>
@@ -306,150 +277,6 @@
</desc>
</func>
<func>
- <name name="token_info" arity="1"/>
- <fsummary>Return information about a token</fsummary>
- <desc>
- <p>Returns a list containing information about the token
- <c><anno>Token</anno></c>. The order of the
- <c><anno>TokenInfoTuple</anno></c>s is not
- defined. See <seealso
- marker="#token_info/2">token_info/2</seealso> for
- information about specific
- <c><anno>TokenInfoTuple</anno></c>s.</p>
- <p>Note that if <c>token_info(Token, TokenItem)</c> returns
- <c>undefined</c> for some <c>TokenItem</c>, the
- item is not included in <c><anno>TokenInfo</anno></c>.</p>
- </desc>
- </func>
- <func>
- <name name="token_info" arity="2" clause_i="1"/>
- <name name="token_info" arity="2" clause_i="2"/>
- <fsummary>Return information about a token</fsummary>
- <type name="token_item"/>
- <type name="attribute_item"/>
- <desc>
- <p>Returns a list containing information about the token
- <c><anno>Token</anno></c>. If one single
- <c><anno>TokenItem</anno></c> is given the returned value is
- the corresponding
- <c>TokenInfoTuple</c>, or <c>undefined</c> if the
- <c>TokenItem</c> has no value. If a list of
- <c><anno>TokenItem</anno></c>s is given the result is a list of
- <c><anno>TokenInfoTuple</anno></c>. The
- <c><anno>TokenInfoTuple</anno></c>s will
- appear with the corresponding <c><anno>TokenItem</anno></c>s in
- the same order as the <c><anno>TokenItem</anno></c>s
- appear in the list of <c>TokenItem</c>s.
- <c><anno>TokenItem</anno></c>s with no value are not included
- in the list of <c><anno>TokenInfoTuple</anno></c>.</p>
- <p>The following <c><anno>TokenInfoTuple</anno></c>s with corresponding
- <c><anno>TokenItem</anno></c>s are valid:</p>
- <taglist>
- <tag><c>{category, </c><seealso marker="#type-category">
- category()</seealso><c>}</c></tag>
- <item><p>The category of the token.</p>
- </item>
- <tag><c>{column, </c><seealso marker="#type-column">
- column()</seealso><c>}</c></tag>
- <item><p>The column where the token begins.</p>
- </item>
- <tag><c>{length, integer() > 0}</c></tag>
- <item><p>The length of the token's text.</p>
- </item>
- <tag><c>{line, </c><seealso marker="#type-line">
- line()</seealso><c>}</c></tag>
- <item><p>The line where the token begins.</p>
- </item>
- <tag><c>{location, </c><seealso marker="#type-location">
- location()</seealso><c>}</c></tag>
- <item><p>The line and column where the token begins, or
- just the line if the column unknown.</p>
- </item>
- <tag><c>{symbol, </c><seealso marker="#type-symbol">
- symbol()</seealso><c>}</c></tag>
- <item><p>The token's symbol.</p>
- </item>
- <tag><c>{text, string()}</c></tag>
- <item><p>The token's text.</p>
- </item>
- </taglist>
- </desc>
- </func>
- <func>
- <name name="attributes_info" arity="1"/>
- <fsummary>Return information about token attributes</fsummary>
- <desc>
- <p>Returns a list containing information about the token
- attributes <c><anno>Attributes</anno></c>. The order of the
- <c><anno>AttributeInfoTuple</anno></c>s is not defined.
- See <seealso
- marker="#attributes_info/2">attributes_info/2</seealso> for
- information about specific
- <c><anno>AttributeInfoTuple</anno></c>s.</p>
- <p>Note that if <c>attributes_info(Token, AttributeItem)</c>
- returns <c>undefined</c> for some <c>AttributeItem</c> in
- the list above, the item is not included in
- <c><anno>AttributesInfo</anno></c>.</p>
- </desc>
- </func>
- <func>
- <name name="attributes_info" arity="2" clause_i="1"/>
- <name name="attributes_info" arity="2" clause_i="2"/>
- <fsummary>Return information about a token attributes</fsummary>
- <type name="attribute_item"/>
- <desc>
- <p>Returns a list containing information about the token
- attributes <c><anno>Attributes</anno></c>. If one single
- <c><anno>AttributeItem</anno></c> is given the returned value is the
- corresponding <c><anno>AttributeInfoTuple</anno></c>,
- or <c>undefined</c> if the <c><anno>AttributeItem</anno></c>
- has no value. If a list of <c><anno>AttributeItem</anno></c>
- is given the result is a list of
- <c><anno>AttributeInfoTuple</anno></c>.
- The <c><anno>AttributeInfoTuple</anno></c>s
- will appear with the corresponding <c><anno>AttributeItem</anno></c>s
- in the same order as the <c><anno>AttributeItem</anno></c>s
- appear in the list of <c><anno>AttributeItem</anno></c>s.
- <c><anno>AttributeItem</anno></c>s with no
- value are not included in the list of
- <c><anno>AttributeInfoTuple</anno></c>.</p>
- <p>The following <c><anno>AttributeInfoTuple</anno></c>s with
- corresponding <c><anno>AttributeItem</anno></c>s are valid:</p>
- <taglist>
- <tag><c>{column, </c><seealso marker="#type-column">
- column()</seealso><c>}</c></tag>
- <item><p>The column where the token begins.</p>
- </item>
- <tag><c>{length, integer() > 0}</c></tag>
- <item><p>The length of the token's text.</p>
- </item>
- <tag><c>{line, </c><seealso marker="#type-line">
- line()</seealso><c>}</c></tag>
- <item><p>The line where the token begins.</p>
- </item>
- <tag><c>{location, </c><seealso marker="#type-location">
- location()</seealso><c>}</c></tag>
- <item><p>The line and column where the token begins, or
- just the line if the column unknown.</p>
- </item>
- <tag><c>{text, string()}</c></tag>
- <item><p>The token's text.</p>
- </item>
- </taglist>
- </desc>
- </func>
- <func>
- <name name="set_attribute" arity="3"/>
- <fsummary>Set a token attribute value</fsummary>
- <desc>
- <p>Sets the value of the <c>line</c> attribute of the token
- attributes <c><anno>Attributes</anno></c>.</p>
- <p>The <c><anno>SetAttributeFun</anno></c> is called with the value of
- the <c>line</c> attribute, and is to return the new value of
- the <c>line</c> attribute.</p>
- </desc>
- </func>
- <func>
<name name="format_error" arity="1"/>
<fsummary>Format an error descriptor</fsummary>
<desc>
diff --git a/lib/stdlib/doc/src/ets.xml b/lib/stdlib/doc/src/ets.xml
index 7b01109ff8..447fe51130 100644
--- a/lib/stdlib/doc/src/ets.xml
+++ b/lib/stdlib/doc/src/ets.xml
@@ -488,14 +488,39 @@ Error: fun containing local Erlang function calls
<item><c>Item=fixed, Value=boolean()</c> <br></br>
Indicates if the table is fixed by any process or not.</item>
- <item>
- <p><c>Item=safe_fixed, Value={FirstFixed,Info}|false</c> <br></br>
+ <item><marker id="info_2_safe_fixed_monotonic_time"/>
+ <p><c>Item=safe_fixed|safe_fixed_monotonic_time, Value={FixationTime,Info}|false</c> <br></br>
</p>
- <p>If the table has been fixed using <c>safe_fixtable/2</c>,
- the call returns a tuple where <c>FirstFixed</c> is the
+ <p>If the table has been fixed using
+ <seealso marker="#safe_fixtable/2"><c>safe_fixtable/2</c></seealso>,
+ the call returns a tuple where <c>FixationTime</c> is the
time when the table was first fixed by a process, which
may or may not be one of the processes it is fixed by
right now.</p>
+ <p>The format and value of <c>FixationTime</c> depends on
+ <c>Item</c>:</p>
+ <taglist>
+ <tag><c>safe_fixed</c></tag>
+ <item><p><c>FixationTime</c> will correspond to the result
+ returned by
+ <seealso marker="erts:erlang#timestamp/0">erlang:timestamp/0</seealso>
+ at the time of fixation. Note that when the system is using
+ single or multi
+ <seealso marker="erts:time_correction#Time_Warp_Modes">time warp
+ modes</seealso> this might produce strange results. This
+ since the usage of <c>safe_fixed</c> is not
+ <seealso marker="erts:time_correction#Time_Warp_Safe_Code">time warp
+ safe</seealso>. Time warp safe code need to use
+ <c>safe_fixed_monotonic_time</c> instead.</p></item>
+
+ <tag><c>safe_fixed_monotonic_time</c></tag>
+ <item><p><c>FixationTime</c> will correspond to the result
+ returned by
+ <seealso marker="erts:erlang#monotonic_time/0">erlang:monotonic_time/0</seealso>
+ at the time of fixation. The usage of <c>safe_fixed_monotonic_time</c> is
+ <seealso marker="erts:time_correction#Time_Warp_Safe_Code">time warp
+ safe</seealso>.</p></item>
+ </taglist>
<p><c>Info</c> is a possibly empty lists of tuples
<c>{Pid,RefCount}</c>, one tuple for every process the
table is fixed by right now. <c>RefCount</c> is the value
@@ -1135,9 +1160,11 @@ clean_all_with_value(Tab,X,Key) ->
table but never releases it, the memory used by the deleted
objects will never be freed. The performance of operations on
the table will also degrade significantly.</p>
- <p>Use <c>info/2</c> to retrieve information about which
- processes have fixed which tables. A system with a lot of
- processes fixing tables may need a monitor which sends alarms
+ <p>Use
+ <seealso marker="#info_2_safe_fixed_monotonic_time"><c>info(Tab,
+ safe_fixed_monotonic_time)</c></seealso> to retrieve information
+ about which processes have fixed which tables. A system with a lot
+ of processes fixing tables may need a monitor which sends alarms
when tables have been fixed for too long.</p>
<p>Note that for tables of the <c>ordered_set</c> type,
<c>safe_fixtable/2</c> is not necessary as calls to
diff --git a/lib/stdlib/doc/src/supervisor.xml b/lib/stdlib/doc/src/supervisor.xml
index 24ff251ce3..815bf4a489 100644
--- a/lib/stdlib/doc/src/supervisor.xml
+++ b/lib/stdlib/doc/src/supervisor.xml
@@ -543,7 +543,10 @@
</item>
<item>
<p><c>active</c> - the count of all actively running child processes
- managed by this supervisor.</p>
+ managed by this supervisor. In the case of <c>simple_one_for_one</c>
+ supervisors, no check is carried out to ensure that each child process
+ is still alive, though the result provided here is likely to be very
+ accurate unless the supervisor is heavily overloaded.</p>
</item>
<item>
<p><c>supervisors</c> - the count of all children marked as