diff options
Diffstat (limited to 'lib/erl_interface/doc/src')
| -rw-r--r-- | lib/erl_interface/doc/src/ei.xml | 62 | ||||
| -rw-r--r-- | lib/erl_interface/doc/src/notes.xml | 142 |
2 files changed, 182 insertions, 22 deletions
diff --git a/lib/erl_interface/doc/src/ei.xml b/lib/erl_interface/doc/src/ei.xml index 7808bfd94f..70af5642da 100644 --- a/lib/erl_interface/doc/src/ei.xml +++ b/lib/erl_interface/doc/src/ei.xml @@ -183,7 +183,7 @@ typedef enum { </func> <func> - <name since="OTP @OTP-15712@"><ret>int</ret><nametext>ei_decode_bitstring(const char *buf, int *index, const char **pp, unsigned int *bitoffsp, size_t *nbitsp)</nametext></name> + <name since="OTP 22.0"><ret>int</ret><nametext>ei_decode_bitstring(const char *buf, int *index, const char **pp, unsigned int *bitoffsp, size_t *nbitsp)</nametext></name> <fsummary>Decode a bitstring.</fsummary> <desc> <p>Decodes a bit string from the binary format.</p> @@ -498,9 +498,9 @@ typedef enum { </func> <func> - <name since="OTP @OTP-15712@"><ret>int</ret> + <name since="OTP 22.0"><ret>int</ret> <nametext>ei_encode_bitstring(char *buf, int *index, const char *p, size_t bitoffs, size_t nbits)</nametext></name> - <name since="OTP @OTP-15712@"><ret>int</ret> + <name since="OTP 22.0"><ret>int</ret> <nametext>ei_x_encode_bitstring(ei_x_buff* x, const char *p, size_t bitoffs, size_t nbits)</nametext></name> <fsummary>Encode a bitstring.</fsummary> <desc> @@ -849,30 +849,48 @@ ei_encode_tuple_header(buf, &i, 0);</pre> </type> <desc> <marker id="ei_set_compat_rel"></marker> - <p>By default, the <c>ei</c> library is only guaranteed - to be compatible with other Erlang/OTP components from the same - release as the <c>ei</c> library itself. For example, - <c>ei</c> from - Erlang/OTP R10 is not compatible with an Erlang emulator - from Erlang/OTP R9 by default.</p> - <p>A call to <c>ei_set_compat_rel(release_number)</c> sets - the <c>ei</c> library in compatibility mode of release - <c>release_number</c>. Valid range of - <c>release_number</c> - is <c>[7, current release]</c>. This makes it possible to - communicate with Erlang/OTP components from earlier releases.</p> + <p>In general, the <c>ei</c> library is guaranteed + to be compatible with other Erlang/OTP components that are 2 major + releases older or newer than the <c>ei</c> library itself.</p> + <p>Sometimes an exception to the above rule has to be made to make new + features (or even bug fixes) possible. A call to + <c>ei_set_compat_rel(release_number)</c> sets + the <c>ei</c> library in compatibility mode of OTP release + <c>release_number</c>.</p> + <p>The only useful value for <c>release_number</c> is currently + <c>21</c>. This will only be useful and have an effect if <em>bit + strings</em> or <em>export funs</em> are received from a connected + node. Before OTP 22, bit strings and export funs were not supported by + <c>ei</c>. They were instead encoded using an undocumented fallback + tuple format when sent from the emulator to <c>ei</c>:</p> + <taglist> + <tag><c>Bit string</c></tag> + <item><p>The term <c><<42, 1:1>></c> was encoded as + <c>{<<42, 128>>, 1}</c>. The first element of the tuple is a + binary and the second element denotes how many bits of the last bytes + are part of the bit string. In this example only the most significant + bit of the last byte (128) is part of the bit string.</p> + </item> + <tag><c>Export fun</c></tag> + <item><p>The term <c>fun lists:map/2</c> was encoded as + <c>{lists,map}</c>. A tuple with the module, function and a missing + arity.</p> + </item> + </taglist> + <p>If <c>ei_set_compat_rel(21)</c> is <em>not</em> called then a connected + emulator will send bit strings and export funs correctly encoded. The + functions <seealso marker="#ei_decode_bitstring"><c>ei_decode_bitstring</c></seealso> + and <seealso marker="#ei_decode_fun"><c>ei_decode_fun</c></seealso> + has to be used to decode such terms. Calling + <c>ei_set_compat_rel(21)</c> should only be done as a workaround to + keep an old implementation alive, which expects to receive the + undocumented tuple formats for bit strings and/or export funs. + </p> <note> <p>If this function is called, it can only be called once and must be called before any other functions in the <c>ei</c> library are called.</p> </note> - <warning> - <p>You can run into trouble if this feature is used - 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> diff --git a/lib/erl_interface/doc/src/notes.xml b/lib/erl_interface/doc/src/notes.xml index fc6a1bb548..c47f0d2bd1 100644 --- a/lib/erl_interface/doc/src/notes.xml +++ b/lib/erl_interface/doc/src/notes.xml @@ -31,6 +31,148 @@ </header> <p>This document describes the changes made to the Erl_interface application.</p> +<section><title>Erl_Interface 3.12</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + The vxworks configure has been updated to respect the + environment CFLAGS.</p> + <p> + Own Id: OTP-15773</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Minor adjustments made to build system for parallel + configure.</p> + <p> + Own Id: OTP-15340 Aux Id: OTP-14625 </p> + </item> + <item> + <p> + The limited support for VxWorks is deprecated as of OTP + 22, and will be removed in OTP 23.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-15621</p> + </item> + <item> + <p>The old legacy <c>erl_interface</c> library (functions + with prefix <c>erl_</c>) is deprecated as of OTP 22, and + will be removed in OTP 23. This does not apply to the + <c>ei</c> library. Reasonably new <c>gcc</c> compilers + will issue deprecation warnings. In order to disable + these warnings, define the macro + <c>EI_NO_DEPR_WARN</c>.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-15622</p> + </item> + <item> + <p>Added support to receive, decode, encode and send both + bit strings and export funs (<c>fun M:F/A</c>).</p> + <p>New functions <c>ei_decode_bitstring</c> and + <c>ei_encode_bitstring</c> have been added in order to + decode and encode bit strings where the number of bits is + not necessary divisible by 8 (a whole number of bytes). + The existing functions <c>ei_decode_fun</c> and + <c>ei_encode_fun</c> can now also handle export funs.</p> + <p>Before this change, bit strings and export funs sent + to an erl_interface c-node were encoded using an + undocumented fallback tuple format. For bit strings + <c>{Binary,BitsInLastByte}</c> and for export funs + <c>{M,F}</c>. Existing c-node implementations expecting + these tuples must be changed to instead use + <c>ei_decode_bitstring</c> and <c>ei_decode_fun</c>. As a + temporary solution you can also build erl_interface with + macro <c>EI_COMPAT=21</c> or call + <c>ei_set_compat_rel(21)</c> to receive the old fallback + tuples.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-15712 Aux Id: OTP-15774 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erl_Interface 3.11.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + <c>erl_interface</c>/<c>ei</c> refused to use node names + with an alive name (the part of the node name preceding + the @ sign) longer than 63 characters and a host name + longer than 64 characters. The total amount of characters + allowed in a node name (alivename@hostname) was thus + limited to 128 characters. These limits applied both to + the own node name as well as node names of other nodes. + Ordinary Erlang nodes limit the node name length to 256 + characters, which meant that you could not communicate + with certain Erlang nodes due to their node name used.</p> + <p> + <c>erl_interface</c>/<c>ei</c> now allow the total amount + of characters in a node name to be up to 256 characters. + These characters may be distributed between alive name + and host name in whatever way needed. That is, the + maximum amount of characters in the alive name may be 254 + and the maximum amount of characters in the host name may + be 254, but in total the node name must not exceed 256 + characters.</p> + <p> + Own Id: OTP-15781 Aux Id: ERIERL-356 </p> + </item> + </list> + </section> + +</section> + +<section><title>Erl_Interface 3.11.2.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + <c>erl_interface</c>/<c>ei</c> refused to use node names + with an alive name (the part of the node name preceding + the @ sign) longer than 63 characters and a host name + longer than 64 characters. The total amount of characters + allowed in a node name (alivename@hostname) was thus + limited to 128 characters. These limits applied both to + the own node name as well as node names of other nodes. + Ordinary Erlang nodes limit the node name length to 256 + characters, which meant that you could not communicate + with certain Erlang nodes due to their node name used.</p> + <p> + <c>erl_interface</c>/<c>ei</c> now allow the total amount + of characters in a node name to be up to 256 characters. + These characters may be distributed between alive name + and host name in whatever way needed. That is, the + maximum amount of characters in the alive name may be 254 + and the maximum amount of characters in the host name may + be 254, but in total the node name must not exceed 256 + characters.</p> + <p> + Own Id: OTP-15781 Aux Id: ERIERL-356 </p> + </item> + </list> + </section> + +</section> + <section><title>Erl_Interface 3.11.2</title> <section><title>Fixed Bugs and Malfunctions</title> |