<itemizedlist spacing="compact">
<listitem>
<para>Just a normal mount point:</para>
- <screen>c:/foo /bar fat32 binary 0 0</screen>
+ <screen> c:/foo /bar fat32 binary 0 0</screen>
</listitem>
<listitem>
<para>A mount point for a textmode mount with case sensitivity switched off:</para>
- <screen>C:/foo /bar/baz ntfs text,posix=0 0 0</screen>
+ <screen> C:/foo /bar/baz ntfs text,posix=0 0 0</screen>
</listitem>
<listitem>
<para>A mount point for a Windows directory with spaces in it:</para>
- <screen>C:/Documents\040and\040Settings /docs ext3 binary 0 0</screen>
+ <screen> C:/Documents\040and\040Settings /docs ext3 binary 0 0</screen>
</listitem>
<listitem>
<para>A mount point for a remote directory without ACL support:</para>
- <screen>//server/share/subdir /srv/subdir smbfs binary,noacl 0 0</screen>
+ <screen> //server/share/subdir /srv/subdir smbfs binary,noacl 0 0</screen>
</listitem>
<listitem>
<para>This is just a comment:</para>
- <screen># This is just a comment</screen>
+ <screen> # This is just a comment</screen>
</listitem>
<listitem>
<para>Set the cygdrive prefix to /mnt:</para>
- <screen>none /mnt cygdrive binary 0 0</screen>
+ <screen> none /mnt cygdrive binary 0 0</screen>
</listitem>
<listitem>
<para>Remount /var to /usr/var:</para>
- <screen>/var /usr/var none bind</screen>
+ <screen> /var /usr/var none bind</screen>
<para>Assuming <filename>/var</filename> points to
<filename>C:/cygwin/var</filename>, <filename>/usr/var</filename> now
also points to <filename>C:/cygwin/var</filename>. This is equivalent
<example id="pathnames-mount-ex">
<title>Displaying the current set of mount points</title>
<screen>
-<prompt>bash$</prompt> <userinput>mount</userinput>
-f:/cygwin/bin on /usr/bin type system (binary,auto)
-f:/cygwin/lib on /usr/lib type system (binary,auto)
-f:/cygwin on / type system (binary,auto)
-e:/src on /usr/src type system (binary)
-c: on /cygdrive/c type user (binary,posix=0,user,noumount,auto)
-e: on /cygdrive/e type user (binary,posix=0,user,noumount,auto)
+
<prompt>bash$</prompt> <userinput>mount</userinput>
+ f:/cygwin/bin on /usr/bin type system (binary,auto)
+ f:/cygwin/lib on /usr/lib type system (binary,auto)
+ f:/cygwin on / type system (binary,auto)
+ e:/src on /usr/src type system (binary)
+ c: on /cygdrive/c type user (binary,posix=0,user,noumount,auto)
+ e: on /cygdrive/e type user (binary,posix=0,user,noumount,auto)
</screen>
</example>
of your registry) are read by a script and the <filename>/etc/fstab</filename>
file is generated from these entries. Note that entries for
<filename>/</filename>, <filename>/usr/bin</filename>, and
-<filename>/usr/lib</filename> are <emphasis>never</emphasis> generated.
+<filename>/usr/lib</filename> are <emphasis role='bold'>never</emphasis>
+generated.
</para>
<para>
<itemizedlist spacing="compact">
<listitem>
<para>All paths starting with a drive specifier</para>
- <screen>
- C:\foo
- C:/foo
- </screen>
+<screen>
+ C:\foo
+ C:/foo
+</screen>
</listitem>
<listitem>
<para>All paths containing at least one backslash as path component</para>
- <screen>
- C:/foo/bar<emphasis role='bold'>\</emphasis>baz/...
- </screen>
+<screen>
+ C:/foo/bar<emphasis role='bold'>\</emphasis>baz/...
+</screen>
</listitem>
<listitem>
<para>UNC paths using backslashes</para>
- <screen>
- \\server\share\...
- </screen>
+<screen>
+ \\server\share\...
+</screen>
</listitem>
</itemizedlist>
<sect2 id="pathnames-win32-api"><title>Using the Win32 file API in Cygwin applications</title>
-<para>Special care must be taken when your application uses Win32 file API
-functions like <function>CreateFile</function> to access files using relative
-pathnames.</para>
+<para>Special care must be taken if your application uses Win32 file API
+functions like <function>CreateFile</function> to access files using
+relative pathnames, or if your application uses functions like
+<function>CreateProcess</function> or <function>ShellExecute</function>
+to start other applications.</para>
<para>When a Cygwin application is started, the Win32 idea of the current
-working directory (CWD) is set to an invalid directory. This works around
-the problem that the Win32 CWD is locked in a way which restricts POSIX
-functionality. However, the side effect is that a call to, for instance,
-<function>CreateFile ("foo", ...);</function> will fail, since the Win32
-notion of the CWD is <emphasis>not</emphasis> the same as the Cygwin notion
-of the CWD.</para>
+working directory (CWD) is set to an <emphasis role='bold'>invalid</emphasis>
+directory. This works around the problem that the Win32 CWD is locked
+in a way which restricts certain POSIX functionality. However, the side
+effect is that a call to, for instance, <function>CreateFile ("foo",
+...);</function> will fail, since the Win32 notion of the CWD is
+not the same as the Cygwin notion of the CWD, and worse, it's a
+directory entirely unsuitable for normal file operations.</para>
<para>So, in general, don't use the Win32 file API in Cygwin applications.
-If you <emphasis>really</emphasis> need to access files using the Win32 API,
-and if you <emphasis>really</emphasis> have to use relative pathnames,
-you have two choices.</para>
+If you <emphasis role='bold'>really</emphasis> need to access files using
+the Win32 API, or if you <emphasis role='bold'>really</emphasis> have to use
+<function>CreateProcess</function> to start applications, rather than
+the POSIX <function>exec(3)</function> familiy of functions, you have to
+make sure that the Win32 CWD is set to some valid directory. To
+accomplish that, you can choose from several methods.</para>
<itemizedlist spacing="compact">
<listitem>
- <para>Either you call <function>SetCurrentDirectory</function> before
- calling the Win32 function which requires a valid Win32 CWD
- (<function>CreateFile</function>, <function>CreateProcess</function>,
- etc).</para>
+ <para>The easiest method is to call</para>
+
+<screen>
+ #include <sys/cygwin.h>
+
+ cygwin_internal (CW_SYNC_WINCWD);
+</screen>
+
+ <para>prior to calling the Win32 functions which require a valid Win32 CWD.
+ This function synchronizes the Win32 CWD with the Cygwin CWD.</para>
+
+ <para>Note that the <function>cygwin_internal (CW_SYNC_WINCWD)</function>
+ call may fail. In that case, it returns with a non-zero value and
+ errno is set appropriately:</para>
+
+ <segmentedlist>
+ <?dbhtml list-presentation="table"?>
+ <seglistitem>
+ <seg><emphasis role='bold'>ENOTDIR</emphasis></seg>
+ <seg>The Cygwin CWD is a virtual path, like /proc, or //, which does not
+ exist as valid directory in the Win32 namespace.</seg>
+ </seglistitem>
+ <seglistitem>
+ <seg><emphasis role='bold'>EACCES</emphasis></seg>
+ <seg>The Cygwin CWD is a directory with restrictive permissions,
+ which make it unusable as Win32 directory.</seg>
+ </seglistitem>
+ <seglistitem>
+ <seg><emphasis role='bold'>ENAMETOOLONG</emphasis></seg>
+ <seg>The Cygwin CWD is too long to be used as Win32 CWD.
+ The Win32 CWD is restricted to 258 characters.</seg>
+ </seglistitem>
+ </segmentedlist>
+
+ <para>You should make sure that you test the return value of
+ <function>cygwin_internal (CW_SYNC_WINCWD)</function>, otherwise
+ your application will potentially not work correctly. If the call
+ failed, you can use the Win32 call <function>SetCurrentDirectory</function>
+ to move to some well-known directory.</para>
+
+ <note><para>After you've synchronized the Win32 CWD with the Cygwin CWD,
+ be aware that the directory is locked, until the process exited, or
+ until the process set the Win32 CWD to some other directory. During that
+ period it will not be possible to rename or remove the directory from
+ other Cygwin applications.</para></note>
+ </listitem>
+ <listitem>
+ <para>If you know where to go to, you can also just call the Win32 function
+ <function>SetCurrentDirectory</function> immediately.</para>
+ </listitem>
+ <listitem>
+ <para>If you need a valid Win32 CWD only for a child application started
+ via <function>CreateProcess</function> and friends, you don't have to
+ set your own Win32 CWD. In that case, just utilize the lpCurrentDirectory
+ parameter. See the description of the <function>CreateProcess</function>
+ function in the MSDN manual pages.</para>
</listitem>
<listitem>
- <para>Or you compile your application as native Win32 (mingw) executable,
- rather than as Cygwin executable.</para>
+ <para>Last, but not least, if you don't need any POSIX function from
+ Cygwin in your specific applciation, consider to compile your application
+ as native Win32 (mingw) executable, rather than as Cygwin executable.</para>
</listitem>
</itemizedlist>
sequence. The sequence starts with an ASCII CAN character (hex code
0x18, equivalent Control-X), followed by the UTF-8 representation of the
character. The result is a filename containing some ugly looking
-characters. While it doesn't <emphasis>look</emphasis> nice, it
-<emphasis>is</emphasis> nice, because Cygwin knows how to convert this
-filename back to UTF-16. The filename will be converted using your
+characters. While it doesn't <emphasis role='bold'>look</emphasis> nice, it
+<emphasis role='bold'>is</emphasis> nice, because Cygwin knows how to convert
+this filename back to UTF-16. The filename will be converted using your
usual character set. However, when Cygwin recognizes an ASCII CAN
character, it skips over the ASCII CAN and handles the following bytes as
a UTF-8 character. Thus, the filename is symmetrically converted back to
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