712 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			712 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
<sect1 id="setup-env"><title>Environment Variables</title>
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<sect2 id="setup-env-ov"><title>Overview</title>
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<para>
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You may wish to specify settings of several important environment
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variables that affect Cygwin's operation.  Some of these settings need
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to be in effect prior to launching the initial Cygwin session (before
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starting your bash shell, for instance).  They should therefore be set
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in the Windows environment; all Windows environment variables are
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imported when Cygwin starts.  Such settings can be
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placed in a .bat file.  An initial file is named Cygwin.bat and is created
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in the Cygwin root directory that you specified during setup.  Note that
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the "Cygwin" option of the Start Menu points to Cygwin.bat.  Edit
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Cygwin.bat to your liking or create your own .bat files to start
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Cygwin processes.</para>
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<para>
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The <envar>CYGWIN</envar> variable is used to configure many global
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settings for the Cygwin runtime system.  Initially you can leave
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<envar>CYGWIN</envar> unset or set it to a value indicating several
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global Cygwin settings, using a syntax like this in the DOS shell,
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before launching bash:</para>
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<screen>
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<prompt>C:\></prompt> <userinput>set CYGWIN=notitle glob</userinput>
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</screen>
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<para>
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This is, of course, just an example.  For all possible settings of the
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<envar>CYGWIN</envar> environment variable, see
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<xref linkend="using-cygwinenv"></xref>.
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</para>
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<para>
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Locale support is controlled by the <envar>LANG</envar> and
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<envar>LC_xxx</envar> environment variables.  Since Cygwin 1.7.2, all of
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them are honored and have a meaning.  For a more detailed description see
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<xref linkend="setup-locale"></xref>.
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</para>
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<para>
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The <envar>PATH</envar> environment variable is used by Cygwin
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applications as a list of directories to search for executable files
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to run.  This environment variable is converted from Windows format
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(e.g. <filename>C:\Windows\system32;C:\Windows</filename>) to UNIX format
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(e.g., <filename>/cygdrive/c/Windows/system32:/cygdrive/c/Windows</filename>)
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when a Cygwin process first starts.
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Set it so that it contains at least the <filename>x:\cygwin\bin</filename>
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directory where "<filename>x:\cygwin</filename> is the "root" of your
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cygwin installation if you wish to use cygwin tools outside of bash.
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This is usually done by the batch file you're starting your shell with.
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</para>
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<para> 
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The <envar>HOME</envar> environment variable is used by many programs to
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determine the location of your home directory and we recommend that it be
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defined.  This environment variable is also converted from Windows format
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when a Cygwin process first starts.  It's usually set in the shell
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profile scripts in the /etc directory.
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</para>
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<para>
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The <envar>TERM</envar> environment variable specifies your terminal
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type.  It is automatically set to <literal>cygwin</literal> if you have
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not set it to something else.
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</para>
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<para>The <envar>LD_LIBRARY_PATH</envar> environment variable is used by
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the Cygwin function <function>dlopen ()</function> as a list of
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directories to search for .dll files to load.  This environment variable
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is converted from Windows format to UNIX format when a Cygwin process
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first starts.  Most Cygwin applications do not make use of the
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<function>dlopen ()</function> call and do not need this variable.
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</para>
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<para>
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In addition to <envar>PATH</envar>, <envar>HOME</envar>,
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and <envar>LD_LIBRARY_PATH</envar>, there are three other environment
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variables which, if they exist in the Windows environment, are
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converted to UNIX format: <envar>TMPDIR</envar>, <envar>TMP</envar>,
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and <envar>TEMP</envar>.  The first is not set by default in the
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Windows environment but the other two are, and they point to the
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default Windows temporary directory.  If set, these variables will be
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used by some Cygwin applications, possibly with unexpected results.
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You may therefore want to unset them by adding the following two lines
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to your <filename>~/.bashrc</filename> file:
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<screen>
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unset TMP
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unset TEMP
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</screen>
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This is done in the default <filename>~/.bashrc</filename> file.
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Alternatively, you could set <envar>TMP</envar>
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and <envar>TEMP</envar> to point to <filename>/tmp</filename> or to
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any other temporary directory of your choice.  For example:
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<screen>
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export TMP=/tmp
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export TEMP=/tmp
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</screen>
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</para>
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</sect2>
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<sect2 id="setup-env-win32"><title>Restricted Win32 environment</title>
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<para>There is a restriction when calling Win32 API functions which
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require a fully set up application environment.  Cygwin maintains its own
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environment in POSIX style.  The Win32 environment is usually stripped
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to a bare minimum and not at all kept in sync with the Cygwin POSIX
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environment.</para>
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<para>If you need the full Win32 environment set up in a Cygwin process,
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you have to call</para>
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<screen>
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#include <sys/cygwin.h>
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cygwin_internal (CW_SYNC_WINENV);
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</screen>
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<para>to synchronize the Win32 environment with the Cygwin environment.
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Note that this only synchronizes the Win32 environment once with the
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Cygwin environment.  Later changes using the <function>setenv</function>
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or <function>putenv</function> calls are not reflected in the Win32
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environment.  In these cases, you have to call the aforementioned
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<function>cygwin_internal</function> call again.</para>
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</sect2>
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</sect1>
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<sect1 id="setup-maxmem"><title>Changing Cygwin's Maximum Memory</title>
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<para>
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Cygwin's heap is extensible.  However, it does start out at a fixed size
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and attempts to extend it may run into memory which has been previously
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allocated by Windows.  In some cases, this problem can be solved by
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adding an entry in the either the <literal>HKEY_LOCAL_MACHINE</literal>
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(to change the limit for all users) or
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<literal>HKEY_CURRENT_USER</literal> (for just the current user) section
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of the registry.  </para>
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<para>
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Add the <literal>DWORD</literal> value <literal>heap_chunk_in_mb</literal> 
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and set it to the desired memory limit in decimal MB. It is preferred to do 
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this in Cygwin using the <command>regtool</command> program included in the 
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Cygwin package.
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(For more information about <command>regtool</command> or the other Cygwin 
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utilities, see <xref linkend="using-utils"></xref> or use the
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<literal>--help</literal> option of each util.)  You should always be careful 
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when using <command>regtool</command> since damaging your system registry can 
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result in an unusable system.  This example sets memory limit to 1024 MB:
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<screen>
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regtool -i set /HKLM/Software/Cygwin/heap_chunk_in_mb 1024
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regtool -v list /HKLM/Software/Cygwin
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</screen>
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</para>
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<para>
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Exit all running Cygwin processes and restart them. Memory can be allocated up 
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to the size of the system swap space minus any the size of any running 
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processes. The system swap should be at least as large as the physically 
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installed RAM and can be modified under the System category of the 
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Control Panel.  
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</para>
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<para>
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Here is a small program written by DJ Delorie that tests the 
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memory allocation limit on your system:
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<screen>
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main()
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{
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  unsigned int bit=0x40000000, sum=0;
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  char *x;
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  while (bit > 4096) 
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  {
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    x = malloc(bit);
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    if (x)
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    sum += bit;
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    bit >>= 1;
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  }
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  printf("%08x bytes (%.1fMb)\n", sum, sum/1024.0/1024.0);
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  return 0;
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}
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</screen>
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You can compile this program using:
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<screen>
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gcc max_memory.c -o max_memory.exe
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</screen>
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Run the program and it will output the maximum amount of allocatable memory.
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</para>
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</sect1>
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<sect1 id="setup-locale"><title>Internationalization</title>
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<sect2 id="setup-locale-ov"><title>Overview</title>
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<para>
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Internationalization support is controlled by the <envar>LANG</envar> and
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<envar>LC_xxx</envar> environment variables.  You can set all of them
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but Cygwin itself only honors the variables <envar>LC_ALL</envar>,
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<envar>LC_CTYPE</envar>, and <envar>LANG</envar>, in this order, according
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to the POSIX standard.  The content of these variables should follow the
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POSIX standard for a locale specifier.  The correct form of a locale
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specifier is</para>
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<screen>
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  language[[_TERRITORY][.charset][@modifier]]
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</screen>
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<para>"language" is a lowercase two character string per ISO 639-1, or,
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if there is no ISO 639-1 code for the language (for instance, "Lower Sorbian"),
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a three character string per ISO 639-3.</para>
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<para>"TERRITORY" is an uppercase two character string per ISO 3166, charset is
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one of a list of supported character sets.  The modifier doesn't matter
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here (though some are recognized, see below).  If you're interested in the
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exact description, you can find it in the online publication of the POSIX
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manual pages on the homepage of the
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<ulink url="http://www.opengroup.org/">Open Group</ulink>.</para>
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<para>Typical locale specifiers are</para>
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<screen>
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  "de_CH"	   language = German, territory = Switzerland, default charset
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  "fr_FR.UTF-8"    language = french, territory = France, charset = UTF-8
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  "ko_KR.eucKR"    language = korean, territory = South Korea, charset = eucKR
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  "syr_SY"         language = Syriac, territory = Syria, default charset
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</screen>
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<para>
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If the locale specifier does not follow the above form, Cygwin checks
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if the locale is one of the locale aliases defined in the file
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<filename>/usr/share/locale/locale.alias</filename>.  If so, and if
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the replacement localename is supported by the underlying Windows,
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the locale is accepted, too.  So, given the default content of the
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<filename>/usr/share/locale/locale.alias</filename> file, the below
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examples would be valid locale specifiers as well.
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</para>
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<screen>
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  "catalan"        defined as "ca_ES.ISO-8859-1" in locale.alias
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  "japanese"       defined as "ja_JP.eucJP"      in locale.alias
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  "turkish"        defined as "tr_TR.ISO-8859-9" in locale.alias
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</screen>
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<para>The file <filename>/usr/share/locale/locale.alias</filename> is
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provided by the gettext package under Cygwin.</para>
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<para>
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At application startup, the application's locale is set to the default
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"C" or "POSIX" locale.  Under Cygwin 1.7.2 and later, this locale defaults
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to the ASCII character set on the application level.  If you want to stick
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to the "C" locale and only change to another charset, you can define this
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by setting one of the locale environment variables to "C.charset".  For
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instance</para>
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<screen>
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  "C.ISO-8859-1"
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</screen>
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<note><para>The default locale in the absence of the aforementioned locale
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environment variables is "C.UTF-8".</para></note>
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<para>Windows uses the UTF-16 charset exclusively to store the names
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of any object used by the Operating System.  This is especially important
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with filenames.  Cygwin uses the setting of the locale environment variables
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<envar>LC_ALL</envar>, <envar>LC_CTYPE</envar>, and <envar>LANG</envar>, to
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determine how to convert Windows filenames from their UTF-16 representation
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to the singlebyte or multibyte character set used by Cygwin.</para>
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<para>
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The setting of the locale environment variables at process startup
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is effective for Cygwin's internal conversions to and from the Windows UTF-16
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object names for the entire lifetime of the current process.  Changing
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the environment variables to another value changes the way filenames are
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converted in subsequently started child processes, but not within the same
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process.</para>
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<para>
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However, even if one of the locale environment variables is set to
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some other value than "C", this does <emphasis>only</emphasis> affect
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how Cygwin itself converts filenames.  As the POSIX standard requires,
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it's the application's responsibility to activate that locale for its
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own purposes, typically by using the call</para>
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<screen>
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  setlocale (LC_ALL, "");
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</screen>
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<para>early in the application code.  Again, so that this doesn't get
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lost:  If the application calls setlocale as above, and there is none
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of the important locale variables set in the environment, the locale
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is set to the default locale, which is "C.UTF-8".</para>
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<para>But what about applications which are not locale-aware?  Per POSIX,
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they are running in the "C" or "POSIX" locale, which implies the ASCII
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charset.  The Cygwin DLL itself, however, will nevertheless use the locale
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set in the environment (or the "C.UTF-8" default locale) for converting
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filenames etc.</para>
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<para>When the locale in the environment specifies an ASCII charset,
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for example "C" or "en_US.ASCII", Cygwin will still use UTF-8
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under the hood to translate filenames.  This allows for easier
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interoperability with applications running in the default "C.UTF-8" locale.
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</para>
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<para>
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Starting with Cygwin 1.7.2, the language and territory are used to
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fetch locale-dependent information from Windows.  If the language and
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territory are not known to Windows, the <function>setlocale</function>
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function fails.</para>
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<para>The following modifiers are recognized.  Any other modifier is simply
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ignored for now.</para>
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<itemizedlist mark="bullet">
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<listitem><para>
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For locales which use the Euro (EUR) as currency, the modifier "@euro"
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can be added to enforce usage of the ISO-8859-15 character set, which
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includes a character for the "Euro" currency sign.
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</para></listitem>
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<listitem><para>
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The default script used for all Serbian language locales (sr_BA, sr_ME, sr_RS,
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and the deprecated sr_CS and sr_SP) is cyrillic.  With the "@latin" modifier
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it gets switched to the latin script with the respective collation behaviour.
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</para></listitem>
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<listitem><para>
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The default charset of the "be_BY" locale (Belarusian/Belarus) is CP1251.
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With the "@latin" modifier it's UTF-8.
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</para></listitem>
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<listitem><para>
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The default charset of the "tt_RU" locale (Tatar/Russia) is ISO-8859-5.
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With the "@iqtelif" modifier it's UTF-8.
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</para></listitem>
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<listitem><para>
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The default charset of the "uz_UZ" locale (Uzbek/Uzbekistan) is ISO-8859-1.
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With the "@cyrillic" modifier it's UTF-8.
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</para></listitem>
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<listitem><para>
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There's a class of characters in the Unicode character set, called the
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"CJK Ambiguous Width" characters.  For these characters, the width
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returned by the wcwidth/wcswidth functions is usually 1.  This can be a
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problem with East-Asian languages, which historically use character sets
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where these characters have a width of 2.  Therefore, wcwidth/wcswidth
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return 2 as the width of these characters when an East-Asian charset such
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as GBK or SJIS is selected, or when UTF-8 is selected and the language is
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specified as "zh" (Chinese), "ja" (Japanese), or "ko" (Korean).  This is
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not correct in all circumstances, hence the locale modifier "@cjknarrow"
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can be used to force wcwidth/wcswidth to return 1 for the ambiguous width
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characters.
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</para></listitem>
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</itemizedlist>
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</sect2>
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<sect2 id="setup-locale-how"><title>How to set the locale</title>
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<itemizedlist mark="bullet">
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<listitem><para>
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Assume that you've set one of the aforementioned environment variables to some
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valid POSIX locale value, other than "C" and "POSIX".  Assume further that
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you're living in Japan.  You might want to use the language code "ja" and the
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territory "JP", thus setting, say, <envar>LANG</envar> to "ja_JP".  You didn't
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set a character set, so what will Cygwin use now?  Starting with Cygwin 1.7.2,
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the default character set is determined by the default Windows ANSI codepage
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for this language and territory.  Cygwin uses a character set which is the
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typical Unix-equivalent to the Windows ANSI codepage.  For instance:</para>
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<screen>
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  "en_US"		ISO-8859-1
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  "el_GR"		ISO-8859-7
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  "pl_PL"		ISO-8859-2
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  "pl_PL@euro"		ISO-8859-15
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  "ja_JP"		EUCJP
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  "ko_KR"		EUCKR
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  "te_IN"		UTF-8
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</screen>
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</listitem>
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<listitem><para>
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You don't want to use the default character set?  In that case you have to
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specify the charset explicitly.  For instance, assume you're from Japan and
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don't want to use the japanese default charset EUC-JP, but the Windows
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default charset SJIS.  What you can do, for instance, is to set the
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<envar>LANG</envar> variable in the <filename>C:\cygwin\Cygwin.bat</filename>
 | 
						|
file which is the batch file to start a Cygwin session from the "Cygwin"
 | 
						|
desktop shortcut.</para>
 | 
						|
 | 
						|
<screen>
 | 
						|
  @echo off
 | 
						|
 | 
						|
  C:
 | 
						|
  chdir C:\cygwin\bin
 | 
						|
  set LANG=ja_JP.SJIS
 | 
						|
  bash --login -i
 | 
						|
</screen>
 | 
						|
 | 
						|
<note><para>For a list of locales supported by your Windows machine, use the new
 | 
						|
<command>locale -a</command> command, which is part of the Cygwin package.
 | 
						|
For a description see <xref linkend="locale"></xref></para></note>
 | 
						|
 | 
						|
<note><para>For a list of supported character sets, see
 | 
						|
<xref linkend="setup-locale-charsetlist"></xref>
 | 
						|
</para></note>
 | 
						|
</listitem>
 | 
						|
 | 
						|
<listitem><para>
 | 
						|
Last, but not least, most singlebyte or doublebyte charsets have a big
 | 
						|
disadvantage.  Windows filesystems use the Unicode character set in the
 | 
						|
UTF-16 encoding to store filename information.  Not all characters
 | 
						|
from the Unicode character set are available in a singlebyte or doublebyte
 | 
						|
charset.  While Cygwin has a workaround to access files with unusual
 | 
						|
characters (see <xref linkend="pathnames-unusual"></xref>), a better
 | 
						|
workaround is to use always the UTF-8 character set.i</para>
 | 
						|
 | 
						|
<para><emphasis>UTF-8 is the only multibyte character set which can represent
 | 
						|
every Unicode character.</emphasis></para>
 | 
						|
 | 
						|
<screen>
 | 
						|
  set LANG=es_MX.UTF-8
 | 
						|
</screen>
 | 
						|
 | 
						|
<para>For a description of the Unicode standard, see the homepage of the
 | 
						|
<ulink url="http://www.unicode.org/">Unicode Consortium</ulink>.
 | 
						|
</para></listitem>
 | 
						|
 | 
						|
</itemizedlist>
 | 
						|
 | 
						|
</sect2>
 | 
						|
 | 
						|
<sect2 id="setup-locale-console"><title>The Windows Console character set</title>
 | 
						|
 | 
						|
<para>Most of the time the Windows console is used to run Cygwin applications.
 | 
						|
While terminal emulations like <command>xterm</command> or
 | 
						|
<command>mintty</command> have a distinct way to set the character set
 | 
						|
used for in- and output, the Windows console hasn't such a way, since it's
 | 
						|
not an application in its own right.</para>
 | 
						|
 | 
						|
<para>This problem is solved in Cygwin as follows.  When a Cygwin
 | 
						|
process is started in a Windows console (either explicitly from cmd.exe,
 | 
						|
or implicitly by, for instance, clicking on the Cygwin desktop icon, or
 | 
						|
running the Cygwin.bat file), the Console character set is determined by the
 | 
						|
setting of the aforementioned internationalization environment variables,
 | 
						|
the same way as described in <xref linkend="setup-locale-how"></xref>.
 | 
						|
</para>
 | 
						|
 | 
						|
<para>What is that good for?  Why not switch the console character set with
 | 
						|
the applications requirements?  After all, the application knows if it uses
 | 
						|
localization or not.  However, what if a non-localized application calls
 | 
						|
a remote application which itself is localized?  This can happen with
 | 
						|
<command>ssh</command> or <command>rlogin</command>.  Both commands don't
 | 
						|
have and don't need localization and they never call
 | 
						|
<function>setlocale</function>.  Setting one of the internationalization
 | 
						|
environment variable to the same charset as the remote machine before
 | 
						|
starting <command>ssh</command> or <command>rlogin</command> fixes that
 | 
						|
problem.</para>
 | 
						|
 | 
						|
</sect2>
 | 
						|
 | 
						|
<sect2 id="setup-locale-problems"><title>Potential Problems when using Locales</title>
 | 
						|
 | 
						|
<para>
 | 
						|
You can set the above internationalization variables not only in
 | 
						|
<filename>Cygwin.bat</filename> or in the Windows environment, but also
 | 
						|
in your Cygwin shell on the fly, even switch to yet another character
 | 
						|
set, and yet another.  In bash for instance:</para>
 | 
						|
 | 
						|
<screen>
 | 
						|
  <prompt>bash$</prompt> export LC_CTYPE="nl_BE.UTF-8"
 | 
						|
</screen>
 | 
						|
 | 
						|
<para>However, here's a problem.  At the start of the first Cygwin process
 | 
						|
in a session, the Windows environment is converted from UTF-16 to UTF-8.
 | 
						|
The environment is another of the system objects stored in UTF-16 in
 | 
						|
Windows.</para>
 | 
						|
 | 
						|
<para>As long as the environment only contains ASCII characters, this is
 | 
						|
no problem at all.  But if it contains native characters, and you're planning
 | 
						|
to use, say, GBK, the environment will result in invalid characters in
 | 
						|
the GBK charset.  This would be especially a problem in variables like
 | 
						|
<envar>PATH</envar>.  To circumvent the worst problems, Cygwin converts
 | 
						|
the <envar>PATH</envar> environment variable to the charset set in the
 | 
						|
environment, if it's different from the UTF-8 charset.</para>
 | 
						|
 | 
						|
<note><para>Per POSIX, the name of an environment variable should only
 | 
						|
consist of valid ASCII characters, and only of uppercase letters, digits, and
 | 
						|
the underscore for maximum portablilty.</para></note>
 | 
						|
 | 
						|
<para>Symbolic links, too, may pose a problem when switching charsets on
 | 
						|
the fly.  A symbolic link contains the filename of the target file the
 | 
						|
symlink points to.  When a symlink had been created with older versions
 | 
						|
of Cygwin, the current ANSI or OEM character set had been used to store
 | 
						|
the target filename, dependent on the old <envar>CYGWIN</envar>
 | 
						|
environment variable setting <envar>codepage</envar> (see <xref
 | 
						|
linkend="cygwinenv-removed-options"></xref>.  If the target filename
 | 
						|
contains non-ASCII characters and you use another character set than
 | 
						|
your default ANSI/OEM charset, the target filename of the symlink is now
 | 
						|
potentially an invalid character sequence in the new character set.
 | 
						|
This behaviour is not different from the behaviour in other Operating
 | 
						|
Systems.  So, if you suddenly can't access a symlink anymore which
 | 
						|
worked all these years before, maybe it's because you switched to
 | 
						|
another character set.  This doesn't occur with symlinks created with
 | 
						|
Cygwin 1.7 or later.  </para>
 | 
						|
 | 
						|
<para>Another problem you might encounter is that older versions of
 | 
						|
Windows did not install all charsets by default.  If you are running
 | 
						|
Windows XP or older, you can open the "Regional and Language Options"
 | 
						|
portion of the Control Panel, select the "Advanced" tab, and select
 | 
						|
entries from the "Code page conversion tables" list.  The following
 | 
						|
entries are useful to cygwin: 932/SJIS, 936/GBK, 949/EUC-KR, 950/Big5,
 | 
						|
20932/EUC-JP.</para>
 | 
						|
 | 
						|
</sect2>
 | 
						|
 | 
						|
<sect2 id="setup-locale-charsetlist"><title>List of supported character sets</title>
 | 
						|
 | 
						|
<para>Last but not least, here's the list of currently supported character
 | 
						|
sets.  The left-hand expression is the name of the charset, as you would use
 | 
						|
it in the internationalization environment variables as outlined above.
 | 
						|
Note that charset specifiers are case-insensitive.  <literal>EUCJP</literal>
 | 
						|
is equivalent to <literal>eucJP</literal> or <literal>eUcJp</literal>.
 | 
						|
Writing the charset in the exact case as given in the list below is a
 | 
						|
good convention, though.
 | 
						|
</para>
 | 
						|
 | 
						|
<para>The right-hand side is the number of the equivalent Windows
 | 
						|
codepage as well as the Windows name of the codepage.  They are only
 | 
						|
noted here for reference.  Don't try to use the bare codepage number or
 | 
						|
the Windows name of the codepage as charset in locale specifiers, unless
 | 
						|
they happen to be identical with the left-hand side.  Especially in case
 | 
						|
of the "CPxxx" style charsets, always use them with the trailing "CP".</para>
 | 
						|
 | 
						|
<para>This works:</para>
 | 
						|
 | 
						|
<screen>
 | 
						|
  set LC_ALL=en_US.CP437
 | 
						|
</screen>
 | 
						|
 | 
						|
<para>This does <emphasis>not</emphasis> work:</para>
 | 
						|
 | 
						|
<screen>
 | 
						|
  set LC_ALL=en_US.437
 | 
						|
</screen>
 | 
						|
 | 
						|
<para>You can find a full list of Windows codepages on the Microsoft MSDN page
 | 
						|
<ulink url="http://msdn.microsoft.com/en-us/library/dd317756(VS.85).aspx">Code Page Identifiers</ulink>.</para>
 | 
						|
 | 
						|
<screen>
 | 
						|
    Charset               Codepage
 | 
						|
    -------------------   -------------------------------------------
 | 
						|
    ASCII                 20127 (US_ASCII)
 | 
						|
 | 
						|
    CP437                   437 (OEM United States)
 | 
						|
    CP720                   720 (DOS Arabic)
 | 
						|
    CP737                   737 (OEM Greek)
 | 
						|
    CP775                   775 (OEM Baltic)
 | 
						|
    CP850                   850 (OEM Latin 1, Western European)
 | 
						|
    CP852                   852 (OEM Latin 2, Central European)
 | 
						|
    CP855                   855 (OEM Cyrillic)
 | 
						|
    CP857                   857 (OEM Turkish)
 | 
						|
    CP858                   858 (OEM Latin 1 + Euro Symbol)
 | 
						|
    CP862                   862 (OEM Hebrew)
 | 
						|
    CP866                   866 (OEM Russian)
 | 
						|
    CP874                   874 (ANSI/OEM Thai)
 | 
						|
    CP932		    932 (Shift_JIS, not exactly identical to SJIS)
 | 
						|
    CP1125                 1125 (OEM Ukraine)
 | 
						|
    CP1250                 1250 (ANSI Central European)
 | 
						|
    CP1251                 1251 (ANSI Cyrillic)
 | 
						|
    CP1252                 1252 (ANSI Latin 1, Western European)
 | 
						|
    CP1253                 1253 (ANSI Greek)
 | 
						|
    CP1254                 1254 (ANSI Turkish)
 | 
						|
    CP1255                 1255 (ANSI Hebrew)
 | 
						|
    CP1256                 1256 (ANSI Arabic)
 | 
						|
    CP1257                 1257 (ANSI Baltic)
 | 
						|
    CP1258                 1258 (ANSI/OEM Vietnamese)
 | 
						|
 | 
						|
    ISO-8859-1            28591 (ISO-8859-1)
 | 
						|
    ISO-8859-2            28592 (ISO-8859-2)
 | 
						|
    ISO-8859-3            28593 (ISO-8859-3)
 | 
						|
    ISO-8859-4            28594 (ISO-8859-4)
 | 
						|
    ISO-8859-5            28595 (ISO-8859-5)
 | 
						|
    ISO-8859-6            28596 (ISO-8859-6)
 | 
						|
    ISO-8859-7            28597 (ISO-8859-7)
 | 
						|
    ISO-8859-8            28598 (ISO-8859-8)
 | 
						|
    ISO-8859-9            28599 (ISO-8859-9)
 | 
						|
    ISO-8859-10             -   (not available)
 | 
						|
    ISO-8859-11             -   (not available)
 | 
						|
    ISO-8859-13           28603 (ISO-8859-13)
 | 
						|
    ISO-8859-14             -   (not available)
 | 
						|
    ISO-8859-15           28605 (ISO-8859-15)
 | 
						|
    ISO-8859-16             -   (not available)
 | 
						|
 | 
						|
    Big5                    950 (ANSI/OEM Traditional Chinese)
 | 
						|
    EUCCN or euc-CN         936 (ANSI/OEM Simplified Chinese)
 | 
						|
    EUCJP or euc-JP       20932 (EUC Japanese)
 | 
						|
    EUCKR or euc-KR         949 (EUC Korean)
 | 
						|
    GB2312                  936 (ANSI/OEM Simplified Chinese)
 | 
						|
    GBK                     936 (ANSI/OEM Simplified Chinese)
 | 
						|
    GEORGIAN-PS             -   (not available)
 | 
						|
    KOI8-R                20866 (KOI8-R Russian Cyrillic)
 | 
						|
    KOI8-U                21866 (KOI8-U Ukrainian Cyrillic)
 | 
						|
    PT154                   -   (not available)
 | 
						|
    SJIS                    -   (not available, almost, but not exactly CP932)
 | 
						|
    TIS620 or TIS-620       874 (ANSI/OEM Thai)
 | 
						|
 | 
						|
    UTF-8 or utf8         65001 (UTF-8)
 | 
						|
</screen>
 | 
						|
 | 
						|
</sect2>
 | 
						|
 | 
						|
</sect1>
 | 
						|
 | 
						|
<sect1 id="setup-files"><title>Customizing bash</title>
 | 
						|
 | 
						|
<para>
 | 
						|
To set up bash so that cut and paste work properly, click on the
 | 
						|
"Properties" button of the window, then on the "Misc" tab.  Make sure
 | 
						|
that "QuickEdit mode" and "Insert mode" are checked.  These settings
 | 
						|
will be remembered next time you run bash from that shortcut. Similarly
 | 
						|
you can set the working directory inside the "Program" tab. The entry
 | 
						|
"%HOME%" is valid, but requires that you set <envar>HOME</envar> in
 | 
						|
the Windows environment.
 | 
						|
</para>
 | 
						|
 | 
						|
<para>
 | 
						|
Your home directory should contain three initialization files
 | 
						|
that control the behavior of bash.  They are
 | 
						|
<filename>.profile</filename>, <filename>.bashrc</filename> and
 | 
						|
<filename>.inputrc</filename>.  The Cygwin base installation creates
 | 
						|
stub files when you start bash for the first time.</para>
 | 
						|
 | 
						|
<para>
 | 
						|
<filename>.profile</filename> (other names are also valid, see the bash man
 | 
						|
page) contains bash commands.  It is executed when bash is started as login
 | 
						|
shell, e.g. from the command <command>bash --login</command>.
 | 
						|
This is a useful place to define and
 | 
						|
export environment variables and bash functions that will be used by bash
 | 
						|
and the programs invoked by bash.  It is a good place to redefine
 | 
						|
<envar>PATH</envar> if needed.  We recommend adding a ":." to the end of
 | 
						|
<envar>PATH</envar> to also search the current working directory (contrary
 | 
						|
to DOS, the local directory is not searched by default).  Also to avoid
 | 
						|
delays you should either <command>unset</command> <envar>MAILCHECK</envar> 
 | 
						|
or define <envar>MAILPATH</envar> to point to your existing mail inbox.
 | 
						|
</para>
 | 
						|
 | 
						|
<para>
 | 
						|
<filename>.bashrc</filename> is similar to
 | 
						|
<filename>.profile</filename> but is executed each time an interactive
 | 
						|
bash shell is launched.  It serves to define elements that are not
 | 
						|
inherited through the environment, such as aliases. If you do not use
 | 
						|
login shells, you may want to put the contents of
 | 
						|
<filename>.profile</filename> as discussed above in this file
 | 
						|
instead.
 | 
						|
</para>
 | 
						|
 | 
						|
<para>
 | 
						|
<screen>
 | 
						|
shopt -s nocaseglob
 | 
						|
</screen>
 | 
						|
will allow bash to glob filenames in a case-insensitive manner.
 | 
						|
Note that <filename>.bashrc</filename> is not called automatically for login 
 | 
						|
shells. You can source it from <filename>.profile</filename>.
 | 
						|
</para>
 | 
						|
 | 
						|
<para>
 | 
						|
<filename>.inputrc</filename> controls how programs using the readline
 | 
						|
library (including <command>bash</command>) behave.  It is loaded
 | 
						|
automatically.  For full details see the <literal>Function and Variable
 | 
						|
Index</literal> section of the GNU <systemitem>readline</systemitem> manual.
 | 
						|
Consider the following settings:
 | 
						|
<screen>
 | 
						|
# Ignore case while completing
 | 
						|
set completion-ignore-case on
 | 
						|
# Make Bash 8bit clean
 | 
						|
set meta-flag on
 | 
						|
set convert-meta off
 | 
						|
set output-meta on
 | 
						|
</screen>
 | 
						|
The first command makes filename completion case insensitive, which can
 | 
						|
be convenient in a Windows environment.  The next three commands allow
 | 
						|
<command>bash</command> to display 8-bit characters, useful for
 | 
						|
languages with accented characters.  Note that tools that do not use
 | 
						|
<systemitem>readline</systemitem> for display, such as
 | 
						|
<command>less</command> and <command>ls</command>, require additional
 | 
						|
settings, which could be put in your <filename>.bashrc</filename>:
 | 
						|
<screen>
 | 
						|
alias less='/bin/less -r'
 | 
						|
alias ls='/bin/ls -F --color=tty --show-control-chars'
 | 
						|
</screen>
 | 
						|
</para>
 | 
						|
 | 
						|
</sect1>
 | 
						|
 |