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-rw-r--r--lib/erl_interface/doc/src/erl_eterm.xml588
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diff --git a/lib/erl_interface/doc/src/erl_eterm.xml b/lib/erl_interface/doc/src/erl_eterm.xml
index e5207a271e..8a46c20432 100644
--- a/lib/erl_interface/doc/src/erl_eterm.xml
+++ b/lib/erl_interface/doc/src/erl_eterm.xml
@@ -28,23 +28,26 @@
<docno></docno>
<approved>Bjarne D&auml;cker</approved>
<checked>Torbj&ouml;rn T&ouml;rnkvist</checked>
- <date>980703</date>
+ <date>1998-07-03</date>
<rev>A</rev>
<file>erl_eterm.xml</file>
</header>
<lib>erl_eterm</lib>
- <libsummary>Functions for Erlang Term Construction</libsummary>
+ <libsummary>Functions for Erlang term construction.</libsummary>
<description>
- <p>This module contains functions for creating and manipulating
- Erlang terms. </p>
+ <p>This module provides functions for creating and manipulating
+ Erlang terms.</p>
+
<p>An Erlang term is represented by a C structure of type
- <c><![CDATA[ETERM]]></c>. Applications should not reference any fields in this
- structure directly, because it may be changed in future releases
+ <c><![CDATA[ETERM]]></c>. Applications should not reference any fields
+ in this structure directly, as it can be changed in future releases
to provide faster and more compact term storage. Instead,
- applications should us the macros and functions provided. </p>
- <p>The following macros each take a single ETERM pointer as an
- argument. They return a non-zero value if the test is true, and 0
- otherwise:</p>
+ applications should use the macros and functions provided.</p>
+
+ <p>Each of the following macros takes a single <c>ETERM</c> pointer as an
+ argument. The macros return a non-zero value if the test is true,
+ otherwise <c>0</c>.</p>
+
<taglist>
<tag><c><![CDATA[ERL_IS_INTEGER(t)]]></c></tag>
<item>True if <c><![CDATA[t]]></c> is an integer.</item>
@@ -55,7 +58,7 @@
<tag><c><![CDATA[ERL_IS_ATOM(t)]]></c></tag>
<item>True if <c><![CDATA[t]]></c> is an atom.</item>
<tag><c><![CDATA[ERL_IS_PID(t)]]></c></tag>
- <item>True if <c><![CDATA[t]]></c> is a Pid (process identifier).</item>
+ <item>True if <c><![CDATA[t]]></c> is a pid (process identifier).</item>
<tag><c><![CDATA[ERL_IS_PORT(t)]]></c></tag>
<item>True if <c><![CDATA[t]]></c> is a port.</item>
<tag><c><![CDATA[ERL_IS_REF(t)]]></c></tag>
@@ -65,29 +68,31 @@
<tag><c><![CDATA[ERL_IS_BINARY(t)]]></c></tag>
<item>True if <c><![CDATA[t]]></c> is a binary.</item>
<tag><c><![CDATA[ERL_IS_LIST(t)]]></c></tag>
- <item>True if <c><![CDATA[t]]></c> is a list with zero or more elements.</item>
+ <item>True if <c><![CDATA[t]]></c> is a list with zero or more
+ elements.</item>
<tag><c><![CDATA[ERL_IS_EMPTY_LIST(t)]]></c></tag>
<item>True if <c><![CDATA[t]]></c> is an empty list.</item>
<tag><c><![CDATA[ERL_IS_CONS(t)]]></c></tag>
- <item>True if <c><![CDATA[t]]></c> is a list with at least one element.</item>
+ <item>True if <c><![CDATA[t]]></c> is a list with at least one
+ element.</item>
</taglist>
+
<p>The following macros can be used for retrieving parts of Erlang
- terms. None of these do any type checking; results are undefined
- if you pass an ETERM* containing the wrong type. For example,
- passing a tuple to ERL_ATOM_PTR() will likely result in garbage.
- </p>
+ terms. None of these do any type checking. Results are undefined
+ if you pass an <c>ETERM*</c> containing the wrong type. For example,
+ passing a tuple to <c>ERL_ATOM_PTR()</c> likely results in garbage.</p>
+
<taglist>
<tag><c><![CDATA[char *ERL_ATOM_PTR(t)]]></c></tag>
- <item/>
+ <item></item>
<tag><c><![CDATA[char *ERL_ATOM_PTR_UTF8(t)]]></c></tag>
- <item>A string representing atom <c><![CDATA[t]]></c>.
- </item>
+ <item>A string representing atom <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_ATOM_SIZE(t)]]></c></tag>
- <item/>
+ <item></item>
<tag><c><![CDATA[int ERL_ATOM_SIZE_UTF8(t)]]></c></tag>
- <item>The length (in bytes) of atom t.</item>
+ <item>The length (in bytes) of atom <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[void *ERL_BIN_PTR(t)]]></c></tag>
- <item>A pointer to the contents of <c><![CDATA[t]]></c></item>
+ <item>A pointer to the contents of <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_BIN_SIZE(t)]]></c></tag>
<item>The length (in bytes) of binary object <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_INT_VALUE(t)]]></c></tag>
@@ -97,9 +102,9 @@
<tag><c><![CDATA[double ERL_FLOAT_VALUE(t)]]></c></tag>
<item>The floating point value of <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[ETERM *ERL_PID_NODE(t)]]></c></tag>
- <item/>
+ <item></item>
<tag><c><![CDATA[ETERM *ERL_PID_NODE_UTF8(t)]]></c></tag>
- <item>The Node in pid <c><![CDATA[t]]></c>.</item>
+ <item>The node in pid <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_PID_NUMBER(t)]]></c></tag>
<item>The sequence number in pid <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_PID_SERIAL(t)]]></c></tag>
@@ -111,16 +116,18 @@
<tag><c><![CDATA[int ERL_PORT_CREATION(t)]]></c></tag>
<item>The creation number in port <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[ETERM *ERL_PORT_NODE(t)]]></c></tag>
- <item/>
+ <item></item>
<tag><c><![CDATA[ETERM *ERL_PORT_NODE_UTF8(t)]]></c></tag>
<item>The node in port <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_REF_NUMBER(t)]]></c></tag>
- <item>The first part of the reference number in ref <c><![CDATA[t]]></c>. Use
- only for compatibility.</item>
+ <item>The first part of the reference number in ref <c><![CDATA[t]]></c>.
+ Use only for compatibility.</item>
<tag><c><![CDATA[int ERL_REF_NUMBERS(t)]]></c></tag>
- <item>Pointer to the array of reference numbers in ref <c><![CDATA[t]]></c>.</item>
+ <item>Pointer to the array of reference numbers in ref
+ <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_REF_LEN(t)]]></c></tag>
- <item>The number of used reference numbers in ref <c><![CDATA[t]]></c>.</item>
+ <item>The number of used reference numbers in ref
+ <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_REF_CREATION(t)]]></c></tag>
<item>The creation number in ref <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[int ERL_TUPLE_SIZE(t)]]></c></tag>
@@ -128,31 +135,38 @@
<tag><c><![CDATA[ETERM *ERL_CONS_HEAD(t)]]></c></tag>
<item>The head element of list <c><![CDATA[t]]></c>.</item>
<tag><c><![CDATA[ETERM *ERL_CONS_TAIL(t)]]></c></tag>
- <item>A List representing the tail elements of list <c><![CDATA[t]]></c>.</item>
+ <item>A list representing the tail elements of list
+ <c><![CDATA[t]]></c>.</item>
</taglist>
</description>
+
<funcs>
<func>
<name><ret>ETERM *</ret><nametext>erl_cons(head, tail)</nametext></name>
- <fsummary>Prepends a term to the head of a list.</fsummary>
+ <fsummary>Prepend a term to the head of a list.</fsummary>
<type>
<v>ETERM *head;</v>
<v>ETERM *tail;</v>
</type>
<desc>
- <p>This function concatenates two Erlang terms, prepending
- <c><![CDATA[head]]></c> onto <c><![CDATA[tail]]></c> and thereby creating a <c><![CDATA[cons]]></c> cell.
- To make a proper list, <c><![CDATA[tail]]></c> should always be a
- list or an empty list. Note that NULL is not a valid list.</p>
- <p><c><![CDATA[head]]></c> is the new term to be added.</p>
- <p><c><![CDATA[tail]]></c> is the existing list to which <c><![CDATA[head]]></c> will
- be concatenated.</p>
+ <p>Concatenates two Erlang terms, prepending <c><![CDATA[head]]></c>
+ onto <c><![CDATA[tail]]></c> and thereby creating a
+ <c><![CDATA[cons]]></c> cell.
+ To make a proper list, <c><![CDATA[tail]]></c> is always to be a list
+ or an empty list. Notice that <c>NULL</c> is not a valid list.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[head]]></c> is the new term to be added.</item>
+ <item><c><![CDATA[tail]]></c> is the existing list to which
+ <c><![CDATA[head]]></c> is concatenated.</item>
+ </list>
<p>The function returns a new list.</p>
- <p><c><![CDATA[ERL_CONS_HEAD(list)]]></c> and <c><![CDATA[ERL_CONS_TAIL(list)]]></c>
+ <p><c><![CDATA[ERL_CONS_HEAD(list)]]></c> and
+ <c><![CDATA[ERL_CONS_TAIL(list)]]></c>
can be used to retrieve the head and tail components
- from the list. <c><![CDATA[erl_hd(list)]]></c> and <c><![CDATA[erl_tl(list)]]></c> will do
+ from the list. <c><![CDATA[erl_hd(list)]]></c> and
+ <c><![CDATA[erl_tl(list)]]></c> do
the same thing, but check that the argument really is a list.</p>
- <p>For example:</p>
+ <p><em>Example:</em></p>
<code type="none"><![CDATA[
ETERM *list,*anAtom,*anInt;
anAtom = erl_mk_atom("madonna");
@@ -165,50 +179,56 @@ erl_free_compound(list);
]]></code>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_copy_term(term)</nametext></name>
- <fsummary>Creates a copy of an Erlang term.</fsummary>
+ <fsummary>Create a copy of an Erlang term.</fsummary>
<type>
<v>ETERM *term;</v>
</type>
<desc>
- <p>This function creates and returns a copy of the Erlang term
+ <p>Creates and returns a copy of the Erlang term
<c><![CDATA[term]]></c>.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_element(position, tuple)</nametext></name>
- <fsummary>Extracts an element from an Erlang tuple.</fsummary>
+ <fsummary>Extract an element from an Erlang tuple.</fsummary>
<type>
<v>int position;</v>
<v>ETERM *tuple;</v>
</type>
<desc>
- <p>This function extracts a specified element from an Erlang
- tuple. </p>
- <p><c><![CDATA[position]]></c> specifies which element to retrieve from
- <c><![CDATA[tuple]]></c>. The elements are numbered starting from 1.</p>
- <p><c><![CDATA[tuple]]></c> is an Erlang term containing at least
- <c><![CDATA[position]]></c> elements.</p>
- <p>The function returns a new Erlang term corresponding to the
- requested element, or NULL if <c><![CDATA[position]]></c> was greater than
- the arity of <c><![CDATA[tuple]]></c>.</p>
+ <p>Extracts a specified element from an Erlang tuple.</p>
+ <iist type="bulleted">
+ <item><c><![CDATA[position]]></c> specifies which element to retrieve
+ from <c><![CDATA[tuple]]></c>. The elements are numbered starting
+ from 1.</item>
+ <item><c><![CDATA[tuple]]></c> is an Erlang term containing at least
+ <c><![CDATA[position]]></c> elements.</item>
+ </iist>
+ <p>Returns a new Erlang term corresponding to the requested element, or
+ <c>NULL</c> if <c><![CDATA[position]]></c> was greater
+ than the arity of <c><![CDATA[tuple]]></c>.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_hd(list)</nametext></name>
- <fsummary>Extracts the first element from a list.</fsummary>
+ <fsummary>Extract the first element from a list.</fsummary>
<type>
<v>ETERM *list;</v>
</type>
<desc>
<p>Extracts the first element from a list.</p>
<p><c><![CDATA[list]]></c> is an Erlang term containing a list.</p>
- <p>The function returns an Erlang term corresponding to the
- head element in the list, or a NULL pointer if <c><![CDATA[list]]></c> was
- not a list.</p>
+ <p>Returns an Erlang term corresponding to the head
+ head element in the list, or a <c>NULL</c> pointer if
+ <c><![CDATA[list]]></c> was not a list.</p>
</desc>
</func>
+
<func>
<name><ret>void</ret><nametext>erl_init(NULL, 0)</nametext></name>
<fsummary>Initialization routine.</fsummary>
@@ -218,42 +238,45 @@ erl_free_compound(list);
</type>
<desc>
<marker id="erl_init"></marker>
- <p>This function must be called before any of the others in
- the <c><![CDATA[erl_interface]]></c> library in order to initialize the
+ <p>This function must be called before any of the others in the
+ <c><![CDATA[Erl_Interface]]></c> library to initialize the
library functions. The arguments must be specified as
<c><![CDATA[erl_init(NULL,0)]]></c>.</p>
</desc>
</func>
+
<func>
<name><ret>int</ret><nametext>erl_iolist_length(list)</nametext></name>
- <fsummary>Return the length of an IO list.</fsummary>
+ <fsummary>Return the length of an I/O list.</fsummary>
<type>
<v>ETERM *list;</v>
</type>
<desc>
- <p>Returns the length of an IO list.
- </p>
- <p><c><![CDATA[list]]></c> is an Erlang term containing an IO list. </p>
- <p>The function returns the length of <c><![CDATA[list]]></c>, or -1 if
- <c><![CDATA[list]]></c> is not an IO list.</p>
- <p>Refer to <c><![CDATA[erl_iolist_to_binary()]]></c> for the definition of
- an IO list. </p>
+ <p>Returns the length of an I/O list.</p>
+ <p><c><![CDATA[list]]></c> is an Erlang term containing an I/O list.</p>
+ <p>Returns the length of <c><![CDATA[list]]></c>, or
+ <c>-1</c> if <c><![CDATA[list]]></c> is not an I/O list.</p>
+ <p>For the definition of an I/O list, see
+ <seealso marker="#erl_iolist_to_binary">
+ <c>erl_iolist_to_binary</c></seealso>.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_iolist_to_binary(term)</nametext></name>
- <fsummary>Converts an IO list to a binary.</fsummary>
+ <fsummary>Convert an I/O list to a binary.</fsummary>
<type>
<v>ETERM *list;</v>
</type>
<desc>
- <p>This function converts an IO list to a binary term.</p>
+ <p>Converts an I/O list to a binary term.</p>
<p><c><![CDATA[list]]></c> is an Erlang term containing a list.</p>
- <p>This function an Erlang binary term, or NULL if <c><![CDATA[list]]></c>
- was not an IO list. </p>
- <p>Informally, an IO list is a deep list of characters and
- binaries which can be sent to an Erlang port. In BNF, an IO
- list is formally defined as follows: </p>
+ <p>Returns an Erlang binary term, or <c>NULL</c> if
+ <c><![CDATA[list]]></c> was not an I/O list.</p>
+ <marker id="erl_iolist_to_binary"></marker>
+ <p>Informally, an I/O list is a deep list of characters and
+ binaries that can be sent to an Erlang port. In BNF, an I/O
+ list is formally defined as follows:</p>
<code type="none"><![CDATA[
iolist ::= []
| Binary
@@ -266,44 +289,49 @@ iohead ::= Binary
]]></code>
</desc>
</func>
+
<func>
<name><ret>char *</ret><nametext>erl_iolist_to_string(list)</nametext></name>
- <fsummary>Converts an IO list to a zero terminated string.</fsummary>
+ <fsummary>Convert an I/O list to a zero-terminated string.</fsummary>
<type>
<v>ETERM *list;</v>
</type>
<desc>
- <p>This function converts an IO list to a '\0' terminated C
- string. </p>
- <p><c><![CDATA[list]]></c> is an Erlang term containing an IO list. The IO
- list must not contain the integer 0, since C strings may not
+ <p>Converts an I/O list to a '\0' terminated C string.</p>
+ <p><c><![CDATA[list]]></c> is an Erlang term containing an I/O list.
+ The I/O list must not contain the integer 0, as C strings may not
contain this value except as a terminating marker.</p>
- <p>This function returns a pointer to a dynamically allocated
- buffer containing a string. If <c><![CDATA[list]]></c> is not an IO list,
- or if <c><![CDATA[list]]></c> contains the integer 0, NULL is returned. It
- is the caller's responsibility free the allocated buffer
- with <c><![CDATA[erl_free()]]></c>. </p>
- <p>Refer to <c><![CDATA[erl_iolist_to_binary()]]></c> for the definition of an
- IO list. </p>
+ <p>Returns a pointer to a dynamically allocated
+ buffer containing a string. If <c><![CDATA[list]]></c> is not an I/O
+ list, or if <c><![CDATA[list]]></c> contains the integer 0,
+ <c>NULL</c> is returned. It
+ is the caller's responsibility to free the allocated buffer
+ with <c><![CDATA[erl_free()]]></c>.</p>
+ <p>For the definition of an I/O list, see
+ <seealso marker="#erl_iolist_to_binary">
+ <c>erl_iolist_to_binary</c></seealso>.</p>
</desc>
</func>
+
<func>
<name><ret>int</ret><nametext>erl_length(list)</nametext></name>
- <fsummary>Determines the length of a list.</fsummary>
+ <fsummary>Determine the length of a list.</fsummary>
<type>
<v>ETERM *list;</v>
</type>
<desc>
<p>Determines the length of a proper list.</p>
- <p><c><![CDATA[list]]></c> is an Erlang term containing proper list. In a
- proper list, all tails except the last point to another list
+ <p><c><![CDATA[list]]></c> is an Erlang term containing a proper list.
+ In a proper list, all tails except the last point to another list
cell, and the last tail points to an empty list.</p>
- <p>Returns -1 if <c><![CDATA[list]]></c> is not a proper list.</p>
+ <p>Returns <c>-1</c> if <c><![CDATA[list]]></c> is not a proper
+ list.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_atom(string)</nametext></name>
- <fsummary>Creates an atom.</fsummary>
+ <fsummary>Create an atom.</fsummary>
<type>
<v>const char *string;</v>
</type>
@@ -311,97 +339,114 @@ iohead ::= Binary
<p>Creates an atom.</p>
<p><c><![CDATA[string]]></c> is the sequence of characters that will be
used to create the atom.</p>
- <p>Returns an Erlang term containing an atom. Note that it is
- the callers responsibility to make sure that <c><![CDATA[string]]></c>
+ <p>Returns an Erlang term containing an atom. Notice that it is
+ the caller's responsibility to ensure that <c><![CDATA[string]]></c>
contains a valid name for an atom.</p>
- <p><c><![CDATA[ERL_ATOM_PTR(atom)]]></c> and <c><![CDATA[ERL_ATOM_PTR_UTF8(atom)]]></c>
- can be used to retrieve the atom name (as a null terminated string). <c><![CDATA[ERL_ATOM_SIZE(atom)]]></c>
- and <c><![CDATA[ERL_ATOM_SIZE_UTF8(atom)]]></c> returns the length of the atom name.</p>
- <note><p>Note that the UTF8 variants were introduced in Erlang/OTP releases R16
- and the string returned by <c>ERL_ATOM_PTR(atom)</c> was not null terminated on older releases.</p>
+ <p><c><![CDATA[ERL_ATOM_PTR(atom)]]></c> and
+ <c><![CDATA[ERL_ATOM_PTR_UTF8(atom)]]></c>
+ can be used to retrieve the atom name (as a null-terminated string).
+ <c><![CDATA[ERL_ATOM_SIZE(atom)]]></c>
+ and <c><![CDATA[ERL_ATOM_SIZE_UTF8(atom)]]></c> return the length
+ of the atom name.</p>
+ <note>
+ <p>The UTF-8 variants were introduced in Erlang/OTP R16 and the
+ string returned by <c>ERL_ATOM_PTR(atom)</c> was not
+ null-terminated on older releases.</p>
</note>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_binary(bptr, size)</nametext></name>
- <fsummary>Creates a binary object.</fsummary>
+ <fsummary>Create a binary object.</fsummary>
<type>
<v>char *bptr;</v>
<v>int size;</v>
</type>
<desc>
- <p>This function produces an Erlang binary object from a
+ <p>Produces an Erlang binary object from a
buffer containing a sequence of bytes.</p>
- <p><c><![CDATA[bptr]]></c> is a pointer to a buffer containing data to be converted.</p>
- <p><c><![CDATA[size]]></c> indicates the length of <c><![CDATA[bptr]]></c>.</p>
- <p>The function returns an Erlang binary object.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[bptr]]></c> is a pointer to a buffer containing
+ data to be converted.</item>
+ <item><c><![CDATA[size]]></c> indicates the length of
+ <c><![CDATA[bptr]]></c>.</item>
+ </list>
+ <p>Returns an Erlang binary object.</p>
<p><c><![CDATA[ERL_BIN_PTR(bin)]]></c> retrieves a pointer to
the binary data. <c><![CDATA[ERL_BIN_SIZE(bin)]]></c> retrieves the
- size. </p>
+ size.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_empty_list()</nametext></name>
- <fsummary>Creates an empty Erlang list.</fsummary>
+ <fsummary>Create an empty Erlang list.</fsummary>
<desc>
- <p>This function creates and returns an empty Erlang list.
- Note that NULL is not used to represent an empty list;
+ <p>Creates and returns an empty Erlang list.
+ Notice that <c>NULL</c> is not used to represent an empty list;
Use this function instead.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_estring(string, len)</nametext></name>
- <fsummary>Creates an Erlang string.</fsummary>
+ <fsummary>Create an Erlang string.</fsummary>
<type>
<v>char *string;</v>
<v>int len;</v>
</type>
<desc>
- <p>This function creates a list from a sequence of bytes.</p>
- <p><c><![CDATA[string]]></c> is a buffer containing a sequence of
- bytes. The buffer does not need to be zero-terminated.</p>
- <p><c><![CDATA[len]]></c> is the length of <c><![CDATA[string]]></c>.</p>
- <p>The function returns an Erlang list object corresponding to
+ <p>Creates a list from a sequence of bytes.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[string]]></c> is a buffer containing a sequence of
+ bytes. The buffer does not need to be zero-terminated.</item>
+ <item><c><![CDATA[len]]></c> is the length of
+ <c><![CDATA[string]]></c>.</item>
+ </list>
+ <p>Returns an Erlang list object corresponding to
the character sequence in <c><![CDATA[string]]></c>.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_float(f)</nametext></name>
- <fsummary>Creates an Erlang float.</fsummary>
+ <fsummary>Create an Erlang float.</fsummary>
<type>
<v>double f;</v>
</type>
<desc>
<p>Creates an Erlang float.</p>
- <p><c><![CDATA[f]]></c> is a value to be converted to an Erlang float.</p>
- <p></p>
- <p>The function returns an Erlang float object with the value
- specified in <c><![CDATA[f]]></c> or <c><![CDATA[NULL]]></c> if
- <c><![CDATA[f]]></c> is not finite.
- </p>
+ <p><c><![CDATA[f]]></c> is a value to be converted to an Erlang
+ float.</p>
+ <p>Returns an Erlang float object with the value
+ specified in <c><![CDATA[f]]></c> or <c><![CDATA[NULL]]></c> if
+ <c><![CDATA[f]]></c> is not finite.</p>
<p><c><![CDATA[ERL_FLOAT_VALUE(t)]]></c> can be used to retrieve the
- value from an Erlang float.</p>
+ value from an Erlang float.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_int(n)</nametext></name>
- <fsummary>Creates an Erlang integer.</fsummary>
+ <fsummary>Create an Erlang integer.</fsummary>
<type>
<v>int n;</v>
</type>
<desc>
<p>Creates an Erlang integer.</p>
- <p><c><![CDATA[n]]></c> is a value to be converted to an Erlang integer.</p>
- <p></p>
- <p>The function returns an Erlang integer object with the
+ <p><c><![CDATA[n]]></c> is a value to be converted to an Erlang
+ integer.</p>
+ <p>Returns an Erlang integer object with the
value specified in <c><![CDATA[n]]></c>.</p>
- <p><c><![CDATA[ERL_INT_VALUE(t)]]></c> can be used to retrieve the value
+ <p><c><![CDATA[ERL_INT_VALUE(t)]]></c> can be used to retrieve the
value from an Erlang integer.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_list(array, arrsize)</nametext></name>
- <fsummary>Creates a list from an array.</fsummary>
+ <fsummary>Create a list from an array.</fsummary>
<type>
<v>ETERM **array;</v>
<v>int arrsize;</v>
@@ -409,44 +454,51 @@ iohead ::= Binary
<desc>
<p>Creates an Erlang list from an array of Erlang terms, such
that each element in the list corresponds to one element in
- the array. </p>
- <p><c><![CDATA[array]]></c> is an array of Erlang terms.</p>
- <p><c><![CDATA[arrsize]]></c> is the number of elements in <c><![CDATA[array]]></c>.</p>
+ the array.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[array]]></c> is an array of Erlang terms.</item>
+ <item><c><![CDATA[arrsize]]></c> is the number of elements in
+ <c><![CDATA[array]]></c>.</item>
+ </list>
<p>The function creates an Erlang list object, whose length
- <c><![CDATA[arrsize]]></c> and whose elements are taken from the terms in
- <c><![CDATA[array]]></c>.</p>
+ <c><![CDATA[arrsize]]></c> and whose elements are taken from the
+ terms in <c><![CDATA[array]]></c>.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_long_ref(node, n1, n2, n3, creation)</nametext></name>
- <fsummary>Creates an Erlang reference.</fsummary>
+ <fsummary>Create an Erlang reference.</fsummary>
<type>
<v>const char *node;</v>
<v>unsigned int n1, n2, n3;</v>
<v>unsigned int creation;</v>
</type>
<desc>
- <p>This function creates an Erlang reference, with 82 bits.</p>
- <p><c><![CDATA[node]]></c> is the name of the C node.</p>
- <p><c><![CDATA[n1]]></c>, <c><![CDATA[n2]]></c> and <c><![CDATA[n3]]></c> can be seen as one big number
- <c><![CDATA[n1*2^64+n2*2^32+n3]]></c> which should be chosen uniquely for
- each reference
- created for a given C node.</p>
- <p><c><![CDATA[creation]]></c> is an arbitrary number.</p>
- <p>Note that <c><![CDATA[n3]]></c> and <c><![CDATA[creation]]></c> are limited in
- precision, so only the low 18 and 2 bits of these numbers
- are actually used.
- </p>
- <p>The function returns an Erlang reference object.</p>
- <p><c><![CDATA[ERL_REF_NODE(ref)]]></c>, <c><![CDATA[ERL_REF_NUMBERS(ref)]]></c>,
- <c><![CDATA[ERL_REF_LEN(ref)]]></c> and
- <c><![CDATA[ERL_REF_CREATION(ref)]]></c> to retrieve the values used
- to create the reference. </p>
+ <p>Creates an Erlang reference, with 82 bits.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[node]]></c> is the name of the C-node.</item>
+ <item><c><![CDATA[n1]]></c>, <c><![CDATA[n2]]></c>, and
+ <c><![CDATA[n3]]></c> can be seen as one big number
+ <c><![CDATA[n1*2^64+n2*2^32+n3]]></c>, which is to be chosen
+ uniquely for each reference created for a given C-node.</item>
+ <item><c><![CDATA[creation]]></c> is an arbitrary number.</item>
+ </list>
+ <p>Notice that <c><![CDATA[n3]]></c> and <c><![CDATA[creation]]></c>
+ are limited in precision, so only the low 18 and 2 bits of these
+ numbers are used.</p>
+ <p>Returns an Erlang reference object.</p>
+ <p><c><![CDATA[ERL_REF_NODE(ref)]]></c>,
+ <c><![CDATA[ERL_REF_NUMBERS(ref)]]></c>,
+ <c><![CDATA[ERL_REF_LEN(ref)]]></c>, and
+ <c><![CDATA[ERL_REF_CREATION(ref)]]></c> can be used to retrieve the
+ values used to create the reference.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_pid(node, number, serial, creation)</nametext></name>
- <fsummary>Creates a process identifier.</fsummary>
+ <fsummary>Create a process identifier.</fsummary>
<type>
<v>const char *node;</v>
<v>unsigned int number;</v>
@@ -454,106 +506,125 @@ iohead ::= Binary
<v>unsigned int creation;</v>
</type>
<desc>
- <p>This function creates an Erlang process identifier. The
+ <p>Creates an Erlang process identifier (pid). The
resulting pid can be used by Erlang processes wishing to
- communicate with the C node.</p>
- <p><c><![CDATA[node]]></c> is the name of the C node.</p>
- <p><c><![CDATA[number]]></c>, <c><![CDATA[serial]]></c> and <c><![CDATA[creation]]></c> are
- arbitrary numbers. Note though, that these are limited in
- precision, so only the low 15, 3 and 2 bits of these numbers
- are actually used.</p>
- <p>The function returns an Erlang pid object.</p>
- <p><c><![CDATA[ERL_PID_NODE(pid)]]></c>, <c><![CDATA[ERL_PID_NUMBER(pid)]]></c>,
- <c><![CDATA[ERL_PID_SERIAL(pid)]]></c> and <c><![CDATA[ERL_PID_CREATION(pid)]]></c>
+ communicate with the C-node.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[node]]></c> is the name of the C-node.</item>
+ <item><c><![CDATA[number]]></c>, <c><![CDATA[serial]]></c>, and
+ <c><![CDATA[creation]]></c> are
+ arbitrary numbers. Notice that these are limited in
+ precision, so only the low 15, 3, and 2 bits of these numbers
+ are used.</item>
+ </list>
+ <p>Returns an Erlang pid object.</p>
+ <p><c><![CDATA[ERL_PID_NODE(pid)]]></c>,
+ <c><![CDATA[ERL_PID_NUMBER(pid)]]></c>,
+ <c><![CDATA[ERL_PID_SERIAL(pid)]]></c>, and
+ <c><![CDATA[ERL_PID_CREATION(pid)]]></c>
can be used to retrieve the four values used to create the pid.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_port(node, number, creation)</nametext></name>
- <fsummary>Creates a port identifier.</fsummary>
+ <fsummary>Create a port identifier.</fsummary>
<type>
<v>const char *node;</v>
<v>unsigned int number;</v>
<v>unsigned int creation;</v>
</type>
<desc>
- <p>This function creates an Erlang port identifier. </p>
- <p><c><![CDATA[node]]></c> is the name of the C node.</p>
- <p><c><![CDATA[number]]></c> and <c><![CDATA[creation]]></c> are arbitrary numbers.
- Note though, that these are limited in
- precision, so only the low 18 and 2 bits of these numbers
- are actually used.</p>
- <p>The function returns an Erlang port object.</p>
- <p><c><![CDATA[ERL_PORT_NODE(port)]]></c>, <c><![CDATA[ERL_PORT_NUMBER(port)]]></c>
- and <c><![CDATA[ERL_PORT_CREATION]]></c> can be used to retrieve the three
- values used to create the port. </p>
+ <p>Creates an Erlang port identifier.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[node]]></c> is the name of the C-node.</item>
+ <item><c><![CDATA[number]]></c> and <c><![CDATA[creation]]></c> are
+ arbitrary numbers. Notice that these are limited in
+ precision, so only the low 18 and 2 bits of these numbers
+ are used.</item>
+ </list>
+ <p>Returns an Erlang port object.</p>
+ <p><c><![CDATA[ERL_PORT_NODE(port)]]></c>,
+ <c><![CDATA[ERL_PORT_NUMBER(port)]]></c>,
+ and <c><![CDATA[ERL_PORT_CREATION]]></c> can be used to retrieve the
+ three values used to create the port.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_ref(node, number, creation)</nametext></name>
- <fsummary>Creates an old Erlang reference.</fsummary>
+ <fsummary>Create an old Erlang reference.</fsummary>
<type>
<v>const char *node;</v>
<v>unsigned int number;</v>
<v>unsigned int creation;</v>
</type>
<desc>
- <p>This function creates an old Erlang reference, with
+ <p>Creates an old Erlang reference, with
only 18 bits - use <c><![CDATA[erl_mk_long_ref]]></c> instead.</p>
- <p><c><![CDATA[node]]></c> is the name of the C node.</p>
- <p><c><![CDATA[number]]></c> should be chosen uniquely for each reference
- created for a given C node.</p>
- <p><c><![CDATA[creation]]></c> is an arbitrary number.</p>
- <p>Note that <c><![CDATA[number]]></c> and <c><![CDATA[creation]]></c> are limited in
- precision, so only the low 18 and 2 bits of these numbers
- are actually used.
- </p>
- <p>The function returns an Erlang reference object.</p>
- <p><c><![CDATA[ERL_REF_NODE(ref)]]></c>, <c><![CDATA[ERL_REF_NUMBER(ref)]]></c>, and
- <c><![CDATA[ERL_REF_CREATION(ref)]]></c> to retrieve the three values used
- to create the reference. </p>
+ <list type="bulleted">
+ <item><c><![CDATA[node]]></c> is the name of the C-node.</item>
+ <item><c><![CDATA[number]]></c> is to be chosen uniquely for each
+ reference created for a given C-node.</item>
+ <item><c><![CDATA[creation]]></c> is an arbitrary number.</item>
+ </list>
+ <p>Notice that <c><![CDATA[number]]></c> and <c><![CDATA[creation]]></c>
+ are limited in precision, so only the low 18 and 2 bits of these
+ numbers are used.</p>
+ <p>Returns an Erlang reference object.</p>
+ <p><c><![CDATA[ERL_REF_NODE(ref)]]></c>,
+ <c><![CDATA[ERL_REF_NUMBER(ref)]]></c>, and
+ <c><![CDATA[ERL_REF_CREATION(ref)]]></c> can be used to retrieve the
+ three values used to create the reference.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_string(string)</nametext></name>
- <fsummary>Creates a string.</fsummary>
+ <fsummary>Create a string.</fsummary>
<type>
<v>char *string;</v>
</type>
<desc>
- <p>This function creates a list from a zero terminated string.</p>
- <p><c><![CDATA[string]]></c> is the zero-terminated sequence of characters
- (i.e. a C string) from which the list will be created.</p>
- <p>The function returns an Erlang list.</p>
+ <p>Creates a list from a zero-terminated string.</p>
+ <p><c><![CDATA[string]]></c> is the zero-terminated sequence of
+ characters
+ (that is, a C string) from which the list will be created.</p>
+ <p>Returns an Erlang list.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_tuple(array, arrsize)</nametext></name>
- <fsummary>Creates an Erlang tuple from an array.</fsummary>
+ <fsummary>Create an Erlang tuple from an array.</fsummary>
<type>
<v>ETERM **array;</v>
<v>int arrsize;</v>
</type>
<desc>
<p>Creates an Erlang tuple from an array of Erlang terms.</p>
- <p><c><![CDATA[array]]></c> is an array of Erlang terms.</p>
- <p><c><![CDATA[arrsize]]></c> is the number of elements in <c><![CDATA[array]]></c>.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[array]]></c> is an array of Erlang terms.</item>
+ <item><c><![CDATA[arrsize]]></c> is the number of elements in
+ <c><![CDATA[array]]></c>.</item>
+ </list>
<p>The function creates an Erlang tuple, whose arity is
- <c><![CDATA[size]]></c> and whose elements are taken from the terms in
- <c><![CDATA[array]]></c>.</p>
- <p>To retrieve the size of a tuple, either use the
- <c><![CDATA[erl_size]]></c> function (which checks the type of the checked
- term and works for a binary as well as for a tuple), or the
+ <c><![CDATA[size]]></c> and whose elements are taken from the terms
+ in <c><![CDATA[array]]></c>.</p>
+ <p>To retrieve the size of a tuple, either use function
+ <c><![CDATA[erl_size]]></c> (which checks the type of the
+ checked term and works for a binary as well as for a tuple) or
<c><![CDATA[ERL_TUPLE_SIZE(tuple)]]></c> returns the arity of a tuple.
- <c><![CDATA[erl_size()]]></c> will do the same thing, but it checks that
- the argument really is a tuple.
+ <c><![CDATA[erl_size()]]></c> does the same thing, but it checks
+ that the argument is a tuple.
<c><![CDATA[erl_element(index,tuple)]]></c> returns the element
- corresponding to a given position in the tuple. </p>
+ corresponding to a given position in the tuple.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_uint(n)</nametext></name>
- <fsummary>Creates an unsigned integer.</fsummary>
+ <fsummary>Create an unsigned integer.</fsummary>
<type>
<v>unsigned int n;</v>
</type>
@@ -561,76 +632,83 @@ iohead ::= Binary
<p>Creates an Erlang unsigned integer.</p>
<p><c><![CDATA[n]]></c> is a value to be converted to an Erlang
unsigned integer.</p>
- <p></p>
- <p>The function returns an Erlang unsigned integer object with
+ <p>Returns an Erlang unsigned integer object with
the value specified in <c><![CDATA[n]]></c>.</p>
<p><c><![CDATA[ERL_INT_UVALUE(t)]]></c> can be used to retrieve the
value from an Erlang unsigned integer.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_mk_var(name)</nametext></name>
- <fsummary>Creates an Erlang variable.</fsummary>
+ <fsummary>Create an Erlang variable.</fsummary>
<type>
<v>char *name;</v>
</type>
<desc>
- <p>This function creates an unbound Erlang variable. The
- variable can later be bound through pattern matching or assignment.</p>
+ <p>Creates an unbound Erlang variable. The variable can later be bound
+ through pattern matching or assignment.</p>
<p><c><![CDATA[name]]></c> specifies a name for the variable.</p>
- <p>The function returns an Erlang variable object with the
- name <c><![CDATA[name]]></c>. </p>
+ <p>Returns an Erlang variable object with the
+ name <c><![CDATA[name]]></c>.</p>
</desc>
</func>
+
<func>
<name><ret>int</ret><nametext>erl_print_term(stream, term)</nametext></name>
- <fsummary>Prints an Erlang term.</fsummary>
+ <fsummary>Print an Erlang term.</fsummary>
<type>
<v>FILE *stream;</v>
<v>ETERM *term;</v>
</type>
<desc>
- <p>This function prints the specified Erlang term to the given
- output stream.</p>
- <p><c><![CDATA[stream]]></c> indicates where the function should send its
- output.</p>
- <p><c><![CDATA[term]]></c> is the Erlang term to print.</p>
- <p>The function returns the number of characters written, or a
- negative value if there was an error.</p>
+ <p>Prints the specified Erlang term to the specified output stream.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[stream]]></c> indicates where the function is to
+ send its output.</item>
+ <item><c><![CDATA[term]]></c> is the Erlang term to print.</item>
+ </list>
+ <p>Returns the number of characters written on success, otherwise a
+ negative value.</p>
</desc>
</func>
+
<func>
<name><ret>void</ret><nametext>erl_set_compat_rel(release_number)</nametext></name>
- <fsummary>Set the erl_interface library in compatibility mode.</fsummary>
+ <fsummary>Set the Erl_Interface library in compatibility mode.</fsummary>
+ <marker id="erl_set_compat_rel"/>
<type>
<v>unsigned release_number;</v>
</type>
<desc>
<marker id="erl_set_compat_rel"></marker>
- <p>By default, the <c><![CDATA[erl_interface]]></c> library is only guaranteed
- to be compatible with other Erlang/OTP components from the same
- release as the <c><![CDATA[erl_interface]]></c> library itself. For example,
- <c><![CDATA[erl_interface]]></c> from the OTP R10 release is not compatible
- with an Erlang emulator from the OTP R9 release by default.</p>
- <p>A call to <c><![CDATA[erl_set_compat_rel(release_number)]]></c> sets the
- <c><![CDATA[erl_interface]]></c> library in compatibility mode of release
- <c><![CDATA[release_number]]></c>. Valid range of <c><![CDATA[release_number]]></c>
+ <p>By default, the <c><![CDATA[Erl_Interface]]></c> library is only
+ guaranteed to be compatible with other Erlang/OTP components from the
+ same release as the <c><![CDATA[Erl_Interface]]></c> library itself.
+ For example, <c><![CDATA[Erl_Interface]]></c> from Erlang/OTP R10
+ is not compatible
+ with an Erlang emulator from Erlang/OTP R9 by default.</p>
+ <p>A call to <c><![CDATA[erl_set_compat_rel(release_number)]]></c> sets
+ the <c><![CDATA[Erl_Interface]]></c> library in compatibility mode of
+ release <c><![CDATA[release_number]]></c>. Valid range of
+ <c><![CDATA[release_number]]></c>
is [7, current release]. This makes it possible to
communicate with Erlang/OTP components from earlier releases.</p>
<note>
<p>If this function is called, it may only be called once
- directly after the call to the
- <seealso marker="#erl_init">erl_init()</seealso> function.</p>
+ directly after the call to function
+ <seealso marker="#erl_init">erl_init()</seealso>.</p>
</note>
<warning>
<p>You may run into trouble if this feature is used
- carelessly. Always make sure that all communicating
+ carelessly. Always ensure that all communicating
components are either from the same Erlang/OTP release, or
from release X and release Y where all components
from release Y are in compatibility mode of release X.</p>
</warning>
</desc>
</func>
+
<func>
<name><ret>int</ret><nametext>erl_size(term)</nametext></name>
<fsummary>Return the arity of a tuple or binary.</fsummary>
@@ -638,49 +716,55 @@ iohead ::= Binary
<v>ETERM *term;</v>
</type>
<desc>
- <p>Returns the arity of an Erlang tuple, or the
- number of bytes in an Erlang binary object. </p>
- <p><c><![CDATA[term]]></c> is an Erlang tuple or an Erlang binary object.</p>
- <p>The function returns the size of <c><![CDATA[term]]></c> as described
- above, or -1 if <c><![CDATA[term]]></c> is not one of the two supported
- types. </p>
+ <p>Returns either the arity of an Erlang tuple or the
+ number of bytes in an Erlang binary object.</p>
+ <p><c><![CDATA[term]]></c> is an Erlang tuple or an Erlang binary
+ object.</p>
+ <p>Returns the size of <c><![CDATA[term]]></c> as described
+ above, or <c>-1</c> if <c><![CDATA[term]]></c> is not one of the two
+ supported types.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_tl(list)</nametext></name>
- <fsummary>Extracts the tail from a list.</fsummary>
+ <fsummary>Extract the tail from a list.</fsummary>
<type>
<v>ETERM *list;</v>
</type>
<desc>
<p>Extracts the tail from a list.</p>
<p><c><![CDATA[list]]></c> is an Erlang term containing a list.</p>
- <p>The function returns an Erlang list corresponding to the
- original list minus the first element, or NULL pointer if
+ <p>Returns an Erlang list corresponding to the
+ original list minus the first element, or <c>NULL</c> pointer if
<c><![CDATA[list]]></c> was not a list.</p>
</desc>
</func>
+
<func>
<name><ret>ETERM *</ret><nametext>erl_var_content(term, name)</nametext></name>
- <fsummary>Extracts the content of a variable.</fsummary>
+ <fsummary>Extract the content of a variable.</fsummary>
<type>
<v>ETERM *term;</v>
<v>char *name;</v>
</type>
<desc>
- <p>This function returns the contents of the specified
- variable in an Erlang term.
- </p>
- <p><c><![CDATA[term]]></c> is an Erlang term. In order for this function
- to succeed, <c><![CDATA[term]]></c> must be an Erlang variable with the
- specified name, or it must be an Erlang list or tuple
- containing a variable with the specified name. Other Erlang
- types cannot contain variables.</p>
- <p><c><![CDATA[name]]></c> is the name of an Erlang variable.</p>
+ <p>Returns the contents of the specified variable in an Erlang term.</p>
+ <list type="bulleted">
+ <item><c><![CDATA[term]]></c> is an Erlang term. In order for this
+ function to succeed,
+ <c><![CDATA[term]]></c> must either be an Erlang variable with
+ the specified name, or it must be an Erlang list or tuple
+ containing a variable with the specified name. Other Erlang
+ types cannot contain variables.</item>
+ <item><c><![CDATA[name]]></c> is the name of an Erlang variable.
+ </item>
+ </list>
<p>Returns the Erlang object corresponding to the value of
- <c><![CDATA[name]]></c> in <c><![CDATA[term]]></c>. If no variable with the name
- <c><![CDATA[name]]></c> was found in <c><![CDATA[term]]></c>, or if <c><![CDATA[term]]></c> is
- not a valid Erlang term, NULL is returned.</p>
+ <c><![CDATA[name]]></c> in <c><![CDATA[term]]></c>. If no variable
+ with the name <c><![CDATA[name]]></c> is found in
+ <c><![CDATA[term]]></c>, or if <c><![CDATA[term]]></c> is
+ not a valid Erlang term, <c>NULL</c> is returned.</p>
</desc>
</func>
</funcs>