From 3e6877b06ae395a9d4310ef664d0360867a47f62 Mon Sep 17 00:00:00 2001 From: Patrik Nyblom Date: Wed, 1 Dec 2010 17:35:40 +0100 Subject: Add documentation about raw filenames and Unicode file name translation mode --- erts/doc/src/erl.xml | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'erts/doc/src') diff --git a/erts/doc/src/erl.xml b/erts/doc/src/erl.xml index 9224d73b6f..77bd952d41 100644 --- a/erts/doc/src/erl.xml +++ b/erts/doc/src/erl.xml @@ -550,6 +550,19 @@

Force the compressed option on all ETS tables. Only intended for test and evaluation.

+ + +

The VM works with file names as if they are encoded using the ISO-latin-1 encoding, disallowing Unicode characters with codepoints beyond 255. This is default on operating systems that have transparent file naming, i.e. all Unixes except MacOSX.

+ + + +

The VM works with file names as if they are encoded using UTF-8 (or some other system specific Unicode encoding). This is the default on operating systems that enforce Unicode encoding, i.e. Windows and MacOSX.

+

By enabling Unicode file name translation on systems where this is not default, you open up to the possibility that some file names can not be interpreted by the VM and therefore will be returned to the program as raw binaries. The option is therefore considered experimental.

+ + + +

Selection between +fnl and +fnu is done based on the current locale settings in the OS, meaning that if you have set your terminal for UTF-8 encoding, the filesystem is expected to use the same encoding for filenames (use with care).

+

Sets the default heap size of processes to the size -- cgit v1.2.3 From 6ea8348174c62812057dd552d0890b2d9d4a3c16 Mon Sep 17 00:00:00 2001 From: Patrik Nyblom Date: Fri, 3 Dec 2010 09:51:00 +0100 Subject: Add documentation to erlang.xml and slight correction to unicode_usage.xml --- erts/doc/src/erlang.xml | 46 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 43 insertions(+), 3 deletions(-) (limited to 'erts/doc/src') diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml index 638f7eef10..78d58a1e56 100644 --- a/erts/doc/src/erlang.xml +++ b/erts/doc/src/erlang.xml @@ -2781,14 +2781,17 @@ os_prompt% open_port(PortName, PortSettings) -> port() Open a port - PortName = {spawn, Command} | {spawn_driver, Command} | {spawn_executable, Command} | {fd, In, Out} + PortName = {spawn, Command} | {spawn_driver, Command} | {spawn_executable, FileName} | {fd, In, Out}  Command = string() +  FileName = [ FileNameChar ] | binary() +  FileNameChar = int() (1..255 or any Unicode codepoint, see description)  In = Out = int() PortSettings = [Opt] -  Opt = {packet, N} | stream | {line, L} | {cd, Dir} | {env, Env} | {args, [ string() ]} | {arg0, string()} | exit_status | use_stdio | nouse_stdio | stderr_to_stdout | in | out | binary | eof +  Opt = {packet, N} | stream | {line, L} | {cd, Dir} | {env, Env} | {args, [ ArgString ]} | {arg0, ArgString} | exit_status | use_stdio | nouse_stdio | stderr_to_stdout | in | out | binary | eof   N = 1 | 2 | 4   L = int()   Dir = string() +   ArgString = [ FileNameChar ] | binary()   Env = [{Name, Val}]    Name = string()    Val = string() | false @@ -2851,7 +2854,26 @@ os_prompt% executed, the appropriate command interpreter will implicitly be invoked, but there will still be no command argument expansion or implicit PATH search.

- + +

The name of the executable as well as the arguments + given in args and arg0 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 file module, the + + file:native_name_encoding/0 function and the + stdlib users guide + for details.

+ + 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. +

If the Command cannot be run, an error exception, with the posix error code as the reason, is raised. The error reason may differ between operating @@ -2954,6 +2976,21 @@ os_prompt% should not be given in this list. The proper executable name will automatically be used as argv[0] where applicable.

+

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.

+ + 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. +

If one, for any reason, wants to explicitly set the program name in the argument vector, the arg0 option can be used.

@@ -2969,6 +3006,9 @@ os_prompt% responds to this is highly system dependent and no specific effect is guaranteed.

+

The unicode file name translation rules of the + args option apply to this option as well.

+ exit_status -- cgit v1.2.3