diff options
Diffstat (limited to 'erts/doc/src/erlang.xml')
| -rw-r--r-- | erts/doc/src/erlang.xml | 234 |
1 files changed, 159 insertions, 75 deletions
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml index bc38055b62..dabfe3f5ad 100644 --- a/erts/doc/src/erlang.xml +++ b/erts/doc/src/erlang.xml @@ -1,4 +1,4 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> @@ -2613,7 +2613,28 @@ os_prompt% </pre> <desc> <p>Returns a port identifier as the result of opening a new Erlang port. A port can be seen as an external Erlang - process. <c><anno>PortName</anno></c> is one of the following:</p> + process. + </p> + <p>The name of the executable as well as the arguments + given in <c>cd</c>, <c>env</c>, <c>args</c> and <c>arg0</c> is subject to + Unicode file name translation if the system is running + in Unicode file name mode. To avoid + translation or force i.e. UTF-8, supply the executable + and/or arguments as a binary in the correct + encoding. See the <seealso + marker="kernel:file">file</seealso> module, the + <seealso marker="kernel:file#native_name_encoding/0"> + file:native_name_encoding/0</seealso> function and the + <seealso marker="stdlib:unicode_usage">stdlib users guide + </seealso> for details.</p> + + <note><p>The characters in the name (if given as a list) + can only be > 255 if the Erlang VM is started in + Unicode file name translation mode, otherwise the name + of the executable is limited to the ISO-latin-1 + character set.</p></note> + + <p><c><anno>PortName</anno></c> is one of the following:</p> <taglist> <tag><c>{spawn, <anno>Command</anno>}</c></tag> <item> @@ -2668,25 +2689,6 @@ os_prompt% </pre> executed, the appropriate command interpreter will implicitly be invoked, but there will still be no command argument expansion or implicit PATH search.</p> - - <p>The name of the executable as well as the arguments - given in <c>args</c> and <c>arg0</c> is subject to - Unicode file name translation if the system is running - in Unicode file name mode. To avoid - translation or force i.e. UTF-8, supply the executable - and/or arguments as a binary in the correct - encoding. See the <seealso - marker="kernel:file">file</seealso> module, the - <seealso marker="kernel:file#native_name_encoding/0"> - file:native_name_encoding/0</seealso> function and the - <seealso marker="stdlib:unicode_usage">stdlib users guide - </seealso> for details.</p> - - <note><p>The characters in the name (if given as a list) - can only be > 255 if the Erlang VM is started in - Unicode file name translation mode, otherwise the name - of the executable is limited to the ISO-latin-1 - character set.</p></note> <p>If the <c><anno>FileName</anno></c> cannot be run, an error exception, with the posix error code as the reason, is @@ -2762,11 +2764,7 @@ os_prompt% </pre> strings. The one exception is <c><anno>Val</anno></c> being the atom <c>false</c> (in analogy with <c>os:getenv/1</c>), which removes the environment variable. - </p> - <p>If Unicode filename encoding is in effect (see the <seealso - marker="erts:erl#file_name_encoding">erl manual - page</seealso>), the strings (both <c>Name</c> and - <c>Value</c>) may contain characters with codepoints > 255.</p> + </p> </item> <tag><c>{args, [ string() | binary() ]}</c></tag> <item> @@ -2794,21 +2792,6 @@ os_prompt% </pre> should not be given in this list. The proper executable name will automatically be used as argv[0] where applicable.</p> - <p>When the Erlang VM is running in Unicode file name - mode, the arguments can contain any Unicode characters and - will be translated into whatever is appropriate on the - underlying OS, which means UTF-8 for all platforms except - Windows, which has other (more transparent) ways of - dealing with Unicode arguments to programs. To avoid - Unicode translation of arguments, they can be supplied as - binaries in whatever encoding is deemed appropriate.</p> - - <note><p>The characters in the arguments (if given as a - list of characters) can only be > 255 if the Erlang - VM is started in Unicode file name mode, - otherwise the arguments are limited to the - ISO-latin-1 character set.</p></note> - <p>If one, for any reason, wants to explicitly set the program name in the argument vector, the <c>arg0</c> option can be used.</p> @@ -2824,9 +2807,6 @@ os_prompt% </pre> responds to this is highly system dependent and no specific effect is guaranteed.</p> - <p>The unicode file name translation rules of the - <c>args</c> option apply to this option as well.</p> - </item> <tag><c>exit_status</c></tag> @@ -3032,7 +3012,10 @@ os_prompt% </pre> (see below), being synchronous, and that the port does <em>not</em> reply with <c>{Port, closed}</c>. Any process may close a port with <c>port_close/1</c>, not only the port owner - (the connected process).</p> + (the connected process). If the calling process is linked to + port identified by <c><anno>Port</anno></c>, an exit signal due + to that link will be received by the process prior to the return + from <c>port_close/1</c>.</p> <p>For comparison: <c><anno>Port</anno> ! {self(), close}</c> fails with <c>badarg</c> if <c><anno>Port</anno></c> cannot be sent to (i.e., <c><anno>Port</anno></c> refers neither to a port nor to a process). If @@ -3041,6 +3024,7 @@ os_prompt% </pre> the port replies with <c>{Port, closed}</c> when all buffers have been flushed and the port really closes, but if the calling process is not the port owner the <em>port owner</em> fails with <c>badsig</c>.</p> + <p>Note that any process can close a port using <c><anno>Port</anno> ! {PortOwner, close}</c> just as if it itself was the port owner, but the reply always goes to the port owner.</p> @@ -3050,8 +3034,17 @@ os_prompt% </pre> implementation has been synchronous. <c>port_close/1</c> is however still fully synchronous. This due to its error behavior.</p> - <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not an open port or - the registered name of an open port.</p> + <p>Failure:</p> + <taglist> + <tag><c>badarg</c></tag> + <item> + If <c><anno>Port</anno></c> is not an identifier of an open + port, or the registered name of an open port. If the calling + process was linked to the previously open port identified by + <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to this exception. + </item> + </taglist> </desc> </func> <func> @@ -3086,8 +3079,11 @@ os_prompt% </pre> <taglist> <tag><c>badarg</c></tag> <item> - If <c><anno>Port</anno></c> is not an open port or the registered name - of an open port. + If <c><anno>Port</anno></c> is not an identifier of an open + port, or the registered name of an open port. If the calling + process was linked to the previously open port identified by + <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to this exception. </item> <tag><c>badarg</c></tag> <item> @@ -3130,8 +3126,11 @@ os_prompt% </pre> <taglist> <tag><c>badarg</c></tag> <item> - If <c><anno>Port</anno></c> is not an open port or the registered name - of an open port. + If <c><anno>Port</anno></c> is not an identifier of an open + port, or the registered name of an open port. If the calling + process was linked to the previously open port identified by + <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to this exception. </item> <tag><c>badarg</c></tag> <item> @@ -3198,9 +3197,20 @@ os_prompt% </pre> implementation has been synchronous. <c>port_connect/2</c> is however still fully synchronous. This due to its error behavior.</p> - <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not an open port - or the registered name of an open port, or if <c>Pid</c> is - not an existing local pid.</p> + <p>Failures:</p> + <taglist> + <tag><c>badarg</c></tag> + <item> + If <c><anno>Port</anno></c> is not an identifier of an open + port, or the registered name of an open port. If the calling + process was linked to the previously open port identified by + <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to this exception. + </item> + <tag><c>badarg</c></tag> + <item>If process identified by <c>Pid</c> is not an existing + local process.</item> + </taglist> </desc> </func> <func> @@ -3236,12 +3246,33 @@ os_prompt% </pre> binary term format and sent to the port.</p> <p>Returns: a term from the driver. The meaning of the returned data also depends on the port driver.</p> - <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not an open port or - the registered name of an open port, if <c><anno>Operation</anno></c> - cannot fit in a 32-bit integer, if the port driver does not - support synchronous control operations, or if the port driver - so decides for any reason (probably something wrong with - <c><anno>Operation</anno></c> or <c><anno>Data</anno></c>).</p> + <p>Failures:</p> + <taglist> + <tag><c>badarg</c></tag> + <item> + If <c><anno>Port</anno></c> is not an identifier of an open + port, or the registered name of an open port. If the calling + process was linked to the previously open port identified by + <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to this exception. + </item> + <tag><c>badarg</c></tag> + <item> + If <c><anno>Operation</anno></c> does not fit in a + 32-bit integer. + </item> + <tag><c>badarg</c></tag> + <item> + If the port driver does not support synchronous control + operations. + </item> + <tag><c>badarg</c></tag> + <item> + If the port driver so decides for any reason (probably + something wrong with <c><anno>Operation</anno></c>, or + <c><anno>Data</anno></c>). + </item> + </taglist> </desc> </func> <func> @@ -3251,7 +3282,12 @@ os_prompt% </pre> <p>Returns a list containing tuples with information about the <c><anno>Port</anno></c>, or <c>undefined</c> if the port is not open. The order of the tuples is not defined, nor are all the - tuples mandatory.</p> + tuples mandatory. + If <c>undefined</c> is returned and the calling process + was linked to a previously open port identified by + <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/1</c>.</p> <p>Currently the result will containt information about the following <c>Item</c>s: <c>registered_name</c> (if the port has a registered name), <c>id</c>, <c>connected</c>, <c>links</c>, @@ -3269,7 +3305,11 @@ os_prompt% </pre> <p><c><anno>Pid</anno></c> is the process identifier of the process connected to the port.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3281,7 +3321,11 @@ os_prompt% </pre> <p><c><anno>Index</anno></c> is the internal index of the port. This index may be used to separate ports.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3293,7 +3337,11 @@ os_prompt% </pre> <p><c><anno>Bytes</anno></c> is the total number of bytes read from the port.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3305,7 +3353,11 @@ os_prompt% </pre> <p><c><anno>Pids</anno></c> is a list of the process identifiers of the processes that the port is linked to.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3320,7 +3372,11 @@ os_prompt% </pre> that these results are highly implementation specific and might change in the future.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3334,7 +3390,11 @@ os_prompt% </pre> that the port itself might have allocated memory which is not included in <c><anno>Bytes</anno></c>.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3346,7 +3406,11 @@ os_prompt% </pre> <p><c><anno>Monitors</anno></c> represent processes that this port is monitoring.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3358,7 +3422,11 @@ os_prompt% </pre> <p><c><anno>Name</anno></c> is the command name set by <seealso marker="#open_port/2">open_port/2</seealso>.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3373,7 +3441,11 @@ os_prompt% </pre> Command}, Options)</seealso>. If the port is not the result of spawning an OS process, the value is <c>undefined</c>.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3389,7 +3461,11 @@ os_prompt% </pre> or <c><anno>Port</anno> ! {Owner, {command, Data}</c>. </p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3412,7 +3488,11 @@ os_prompt% </pre> in bytes, queued by the port using the ERTS driver queue implementation.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -3424,7 +3504,11 @@ os_prompt% </pre> <p><c><anno>RegisteredName</anno></c> is the registered name of the port. If the port has no registered name, <c>[]</c> is returned.</p> <p>If the port identified by <c><anno>Port</anno></c> is not open, - <c>undefined</c> is returned.</p> + <c>undefined</c> is returned. If <c>undefined</c> is returned and + the calling process was linked to a previously open port identified + by <c><anno>Port</anno></c>, an exit signal due to this link + was received by the process prior to the return from + <c>port_info/2</c>.</p> <p>Failure: <c>badarg</c> if <c><anno>Port</anno></c> is not a local port identifier, or an atom.</p> </desc> @@ -4727,8 +4811,8 @@ true</pre> <name name="statistics" arity="1" clause_i="6"/> <fsummary>Information about the run-queue</fsummary> <desc> - <p>Returns the length of the run queue, that is, the number - of processes that are ready to run.</p> + <p>Returns the total length of the run queues, that is, the number + of processes that are ready to run on all available run queues.</p> </desc> </func> <func> |