newlib/winsup/doc/new-features.xml

<?xml version="1.0" encoding='UTF-8'?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
		"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">

<sect1 id="ov-new"><title>What's new and what changed in Cygwin</title>

<sect2 id="ov-new2.1"><title>What's new and what changed in 2.1</title>

<itemizedlist mark="bullet">

<listitem><para>
Handle pthread stacksizes as in GLibc:  Default to RLIMIT_STACK resource.
Allow to set RLIMIT_STACK via setrlimit.  Default RLIMIT_STACK to value
from executable header as described on the MSDN website
<ulink url="https://msdn.microsoft.com/en-us/library/windows/desktop/ms686774.aspx">Thread Stack Size</ulink>
Default stacksize to 2 Megs in case RLIMIT_STACK is set to RLIM_INFINITY.
</para></listitem>

<listitem><para>
First cut of an implementation to allow signal handlers running on an
alternate signal stack. 
</para></listitem>

<listitem><para>
New API sigaltstack, plus definitions for SA_ONSTACK, SS_ONSTACK,
SS_DISABLE, MINSIGSTKSZ, SIGSTKSZ.
</para></listitem>

<listitem><para>
New API: sethostname.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new2.0"><title>What's new and what changed in 2.0</title>

<itemizedlist mark="bullet">

<listitem><para>
basename(3) now comes in two flavors, POSIX and GNU.  The POSIX version is
the default.  You get the GNU version after

<screen>
  #define _GNU_SOURCE
  #include &lt;string.h&gt;
</screen>
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.35"><title>What's new and what changed in 1.7.35</title>

<itemizedlist mark="bullet">

<listitem><para>
Performance improvements of the new account DB handling.
</para></listitem>

<listitem><para>
Since 1.7.34, chmod does not always affect the POSIX permission mask as
returned by stat(2) or printed by ls(1), due to the improved POSIX ACL
handling.  However, that's still far from perfect, so, as a temporary
workaround, chmod now checks if secondary groups and users in the ACL
have more permissions than the primary group.  If so, the permissions of
the secondary users and groups will be reduced according to the mask
given by the new primary group permissions.  I.e, chmod 600 will remove
all permissions from the primary group as well as all secondary user and
group entries in the ACL.
</para></listitem>

<listitem><para>
Change handling of group permissions if owner SID == group SID.  Now the
group permissions don't mirror the user permissions anymore, thus
leading to less hassle with security-conscious applications.
</para></listitem>

<listitem><para>
Allow group SID to be the same as owner SID for "Microsoft Accounts".
Those have the group in their user token set to the owner SID by
default.  Drop the workaround to change their primary group to "Users".
It's not required anymore due to the aforementioned changes.
</para></listitem>

<listitem><para>
Change getfacl long options from --all to --access and from --dir to
--default, along the lines of the Linux getfacl tool.
</para></listitem>

<listitem><para>
Don't raise a SIGSYS signal in the XSI IPC functions if cygserver is not
running.  Just return -1 with errno set to ENOSYS.
</para></listitem>

<listitem><para>
New APIs: cabsl, cimagl, creall, finitel, hypotl, sqrtl.
</para></listitem>

<listitem><para>
New API: issetugid.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.34"><title>What's new and what changed in 1.7.34</title>

<itemizedlist mark="bullet">

<listitem><para>
Cygwin can now generate passwd/group entries directly from Windows user
databases (local SAM or Active Directory), thus allowing to run Cygwin
without having to create /etc/passwd and /etc/group files.  Introduce
/etc/nsswitch.conf file to configure passwd/group handling.
</para>

<para>
For bordercase which require to use /etc/passwd and /etc/group files,
change mkpasswd/mkgroup to generate passwd/group entries compatible with
the entries read from SAM/AD.
</para>

<para>For a description of this exciting new feature see
<xref linkend="ntsec"></xref>.
</para></listitem>

<listitem><para>
Add -b/--remove-all option to setfacl to reduce the ACL to only the entries
representing POSIX permission bits.
</para></listitem>

<listitem><para>
Add -k/--remove-default option to setfacl to remove all default ACL entries
from an ACL.
</para></listitem>

<listitem><para>
Add restore action to regtool.
</para></listitem>

<listitem><para>
Make gethostbyname2 handle numeric host addresses as well as the
reserved domain names "localhost" and "invalid" per RFC 6761.
</para></listitem>

<listitem><para>
Revamp Solaris ACL implementation to more closely work like POSIX ACLs
are supposed to work.  Finally implement a CLASS_OBJ emulation.  Update
getfacl(1)/setfacl(1) accordingly.
</para></listitem>

<listitem><para>
The xdr functions are no longer exported for newly built executables.
Use libtirpc-devel instead.
</para></listitem>

<listitem><para>
32 bit only: Change default values for socket buffer size to raise
performance on 10Gb networks.
</para></listitem>

<listitem><para>
When spawning a process under another user account, merge the user's
default Windows environment into the new process' environment.
</para></listitem>

<listitem><para>
New APIs: qsort_r, __bsd_qsort_r.
</para></listitem>

<listitem><para>
New API: wcstold.
</para></listitem>

<listitem><para>
New APIs: __fbufsize, __flbf, __fpending, __freadable, __freading,
__fsetlocking, __fwritable, __fwriting.
</para></listitem>

<listitem><para>
New APIs: clearerr_unlocked, feof_unlocked, ferror_unlocked, fflush_unlocked,
fgetc_unlocked, fgets_unlocked, fgetwc_unlocked, fgetws_unlocked,
fileno_unlocked, fputc_unlocked, fputs_unlocked, fputwc_unlocked,
fputws_unlocked, fread_unlocked, fwrite_unlocked, getwc_unlocked,
getwchar_unlocked, putwc_unlocked, putwchar_unlocked.
</para></listitem>

<listitem><para>
New API: sockatmark.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.33"><title>What's new and what changed in 1.7.33</title>

<itemizedlist mark="bullet">

<listitem><para>
/proc/cygdrive is a new symlink pointing to the current cygdrive prefix.
This can be utilized in scripts to access paths via cygdrive prefix,
even if the cygdrive prefix has been changed by the user.
</para></listitem>

<listitem><para>
/proc/partitions now prints the windows mount points the device is
mounted on.  This allows to recognize the underlying Windows devices of
the Cygwin raw device names.
</para></listitem>

<listitem><para>
New API: quotactl, designed after the Linux/BSD function, but severely
restricted:  Windows only supports user block quotas on NTFS, no group
quotas, no inode quotas, no time constraints.
</para></listitem>

<listitem><para>
New APIs: ffsl, ffsll (glibc extensions).
</para></listitem>

<listitem><para>
New API: stime (SVr4).
</para></listitem>

<listitem><para>
Provide Cygwin documentation (PDFs and HTML) for offline usage in
<filename>/usr/share/doc/cygwin-${version}</filename>.
</para></listitem>

<listitem><para>
New internal exception handling based on SEH on 64 bit Cygwin.
</para></listitem>

<listitem><para>
When exec'ing applications, check if $PATH exists and is non-empty.  If
not, add PATH variable with Cygwin installation directory as content to
Windows environment to allow loading of Cygwin system DLLs.
</para></listitem>

<listitem><para>
Disable CYGWIN "dosfilewarning" option by default.
</para></listitem>

<listitem><para>
Improve various header files for C++- and standards-compliance.
</para></listitem>

<listitem><para>
Doug Lea malloc implementation update from 2.8.3 to the latest 2.8.6.
</para></listitem>

<listitem><para>
atexit(3) is now exported as statically linked function from libcygwin.a.
This allows reliable access to the DSO handle of the caller for newly
built executables.  The former atexit entry point into the DLL remains
for backward compatibility only.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.32"><title>What's new and what changed in 1.7.32</title>

<itemizedlist mark="bullet">

<listitem><para>
Export __cxa_atexit and __cxa_finalize to allow C++ standards-compliant
destructor handling in libstdc++ and g++ compiled code.

Please note that, in order to benefit from this new feature, C++ code
must be recompiled with the upcoming gcc 4.8.3-3 release which will
enable the -fuse-cxa-atexit flag by default, and that C++ applications
using this feature will not run on older Cygwin releases.
</para></listitem>

<listitem><para>
Support more recent CPU flags in /proc/cpuinfo.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.31"><title>What's new and what changed in 1.7.31</title>

<itemizedlist mark="bullet">

<listitem><para>
Improve performance of send(2), sendto(2), sendmsg(2) when using small
input buffers.
</para></listitem>

<listitem><para>
The default pthread_mutex type is now PTHREAD_MUTEX_NORMAL, rather than
PTHREAD_MUTEX_ERRORCHECK, just as on Linux.
</para></listitem>

<listitem><para>
Align pthread_attr stack functions more closely to Linux.
</para></listitem>

<listitem><para>
Mark pthread_attr_getstackaddr and pthread_attr_setstackaddr as deprecated,
as on Linux.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.29"><title>What's new and what changed in 1.7.29</title>

<itemizedlist mark="bullet">

<listitem><para>
Allow quoting of arguments to the CYGWIN environment variable, i.e.,
set CYGWIN=error_start="c:\bin\someprogram -T"
</para></listitem>

<listitem><para>
Console screen clearing works more like xterm or mintty.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.28"><title>What's new and what changed in 1.7.28</title>

<itemizedlist mark="bullet">

<listitem><para>
popen now supports the Glibc 'e' flag to set the FD_CLOEXEC flag on the pipe
in a thread-safe way.
</para></listitem>

<listitem><para>
New netinet/ip6.h header.
</para></listitem>

<listitem><para>
Switch to BSD FILE stream fopen/exit semantics, as in all BSD variants
and Linux/GLibc:  Don't fflush/lseek a FILE stream on fclose and exit,
if it only has been read from.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.27"><title>What's new and what changed in 1.7.27</title>

<itemizedlist mark="bullet">

<listitem><para>
Don't create native symlinks with target paths having long path prefixes
"\\?\" if the target path is shorter than MAX_PATH characters.  This works
around a Windows 8.1 bug:  The ShellExecuteW fails if the lpFile parameter
points to a native NTFS symlink with a target path prefixed with "\\?\".
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.26"><title>What's new and what changed in 1.7.26</title>

<itemizedlist mark="bullet">

<listitem><para>
getaddrinfo now supports glibc-specific International Domain Name (IDN)
extension flags: AI_IDN, AI_CANONIDN, AI_IDN_ALLOW_UNASSIGNED,
AI_IDN_USE_STD3_ASCII_RULES.
</para></listitem>

<listitem><para>
getnameinfo now supports glibc-specific International Domain Name (IDN)
extension flags: NI_IDN, NI_IDN_ALLOW_UNASSIGNED, NI_IDN_USE_STD3_ASCII_RULES.
</para></listitem>

<listitem><para>
Slightly improve randomness of /dev/random emulation.
</para></listitem>

<listitem><para>
Allow to use advisory locking on any device.  POSIX fcntl and lockf locking
works with any device, BSD flock locking only with devices backed by an OS
handle.  Right now this excludes console windows on pre Windows 8, as well as
almost all virtual files under /proc from BSD flock locking.
</para></listitem>

<listitem><para>
The header /usr/include/exceptions.h, containing implementation details for
32 bit Windows' exception handling only, has been removed.
</para></listitem>

<listitem><para>
Preliminary, experimental support of the posix_spawn family of functions.
New associated header /usr/include/spawn.h.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.25"><title>What's new and what changed in 1.7.25</title>

<itemizedlist mark="bullet">

<listitem><para>
Change magic number associated with process information block so that 32-bit
Cygwin processes don't try to interpret 64-bit information and vice-versa.
</para></listitem>

<listitem><para>
Redefine content of mtget tape info struct to allow fetching the number of
partitions on a tape.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.24"><title>What's new and what changed in 1.7.24</title>

<itemizedlist mark="bullet">

<listitem><para>
Allow application override of posix_memalign.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.23"><title>What's new and what changed in 1.7.23</title>

<itemizedlist mark="bullet">

<listitem><para>
Added CYGWIN environment variable keyword "wincmdln" which causes Cygwin to
send the full windows command line to any subprocesses.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.22"><title>What's new and what changed in 1.7.22</title>

<itemizedlist mark="bullet">

<listitem><para>
Support for /dev/mem, /dev/kmem and /dev/port removed, since OS support
was limited to 32 bit Windows XP only.
</para></listitem>

<listitem><para>
Added cygwin GetCommandLine wrappers which will allow Cygwin programs to
(appear to) use the Windows command line functions.
</para></listitem>

<listitem><para>
regcomp(3) now allows character values >= 0x80 if the current codeset is
ASCII (default codeset in the "C"/"POSIX" locale).  This allows patterns
containing arbitrary byte values as GLibc's regcomp.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.21"><title>What's new and what changed in 1.7.21</title>

<itemizedlist mark="bullet">

<listitem><para>
New API: rawmemchr.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.19"><title>What's new and what changed in 1.7.19</title>

<itemizedlist mark="bullet">

<listitem><para>
Drop support for Windows 2000 and Windows XP pre-SP3.
</para></listitem>

<listitem><para>
Add support for building a 64 bit version of Cygwin on x86_64 natively.
</para></listitem>

<listitem><para>
Add support for creating native NTFS symlinks starting with Windows Vista
by setting the CYGWIN=winsymlinks:native or CYGWIN=winsymlinks:nativestrict
option.
</para></listitem>

<listitem><para>
Add support for AFS filesystem.
</para></listitem>

<listitem><para>
Preliminary support for mandatory locking via fcntl/flock/lockf, using Windows
locking semantics.  New F_LCK_MANDATORY fcntl command.
</para></listitem>

<listitem><para>
New APIs: __b64_ntop, __b64_pton, arc4random, arc4random_addrandom,
arc4random_buf, arc4random_stir, arc4random_uniform.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.18"><title>What's new and what changed in 1.7.18</title>

<itemizedlist mark="bullet">

<listitem><para>Added Windows console cursor appearance support.</para>

  <itemizedlist mark="bullet">

  <listitem><para>
  Show/Hide Cursor mode (DECTCEM): "ESC[?25h" / "ESC[?25l"
  </para></listitem>

  <listitem><para>
  Set cursor style (DECSCUSR): "ESC[n q" (note the space before the q);
  where n is 0, 1, 2 for block cursor, 3, 4 for underline cursor (all
  disregarding blinking mode), or > 4 to set the cursor height to a
  percentage of the cell height.
  </para></listitem>

  </itemizedlist>

</listitem>

<listitem><para>
For performance reasons, Cygwin does not try to create sparse files
automatically anymore, unless you use the new "sparse" mount option.
</para></listitem>

<listitem><para>
New API: cfsetspeed.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.17"><title>What's new and what changed in 1.7.17</title>

<itemizedlist mark="bullet">

<listitem><para>
Support the "e" flag to fopen(3).  This is a Glibc extension which
allows to fopen the file with the O_CLOEXEC flag set.
</para></listitem>

<listitem><para>
Support the "x" flag to fopen(3).  This is a Glibc/C11 extension which
allows to open the file with the O_EXCL flag set.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.16"><title>What's new and what changed in 1.7.16</title>

<itemizedlist mark="bullet">

<listitem><para>
New API: getmntent_r, memrchr.
</para></listitem>

<listitem><para>
Recognize ReFS filesystem.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.15"><title>What's new and what changed in 1.7.15</title>

<itemizedlist mark="bullet">

<listitem><para>
CYGWIN=pipe_byte option now forces the opening of pipes in byte mode rather than message mode.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.14"><title>What's new and what changed in 1.7.14</title>

<itemizedlist mark="bullet">

<listitem><para>
Add mouse reporting modes 1005, 1006 and 1015 to console window.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.13"><title>What's new and what changed in 1.7.13</title>

<itemizedlist mark="bullet">

<listitem><para>
mkpasswd and mkgroup now try to print an entry for the TrustedInstaller
account existing since Windows Vista/Server 2008.
</para></listitem>

<listitem><para>
Terminal typeahead when switching from canonical to non-canonical mode
is now properly flushed.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.12"><title>What's new and what changed in 1.7.12</title>

<itemizedlist mark="bullet">

<listitem><para>
Cygwin now automatically populates the /dev directory with all existing
POSIX devices.
</para></listitem>

<listitem><para>
Add virtual /proc/PID/mountinfo file.
</para></listitem>

<listitem><para>
flock now additionally supports the following scenario, which requires
  to propagate locks to the parent process:
   <screen>
    (
      flock -n 9 || exit 1
      # ... commands executed under lock ...
    } 9>/var/lock/mylockfile
   </screen>
  Only propagation to the direct parent process is supported so far,
  not to grand parents or sibling processes.
</para></listitem>

<listitem><para>
Add a "detect_bloda" setting for the CYGWIN environment variable to help
finding potential BLODAs.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.11"><title>What's new and what changed in 1.7.11</title>

<itemizedlist mark="bullet">

<listitem><para>
New <command>pldd</command> command for listing DLLs loaded by a process.
</para></listitem>

<listitem><para>
New API: scandirat.
</para></listitem>

<listitem><para>
Change the way remote shares mapped to drive letters are recognized when
creating the cygdrive directory.  If Windows claims the drive is
unavailable, don't show it in the cygdrive directory listing.
</para></listitem>

<listitem><para>
Raise default stacksize of pthreads from 512K to 1 Meg.  It can still be
changed using the pthread_attr_setstacksize call.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.10"><title>What's new and what changed in 1.7.10</title>

<itemizedlist mark="bullet">

<listitem><para>
Drop support for Windows NT4.
</para></listitem>

<listitem><para>
The CYGWIN environment variable options "envcache", "strip_title", "title",
"tty", and "upcaseenv" have been removed.
</para></listitem>

<listitem><para>
If the executable (and the system) is large address aware, the application heap
will be placed in the large memory area.  The <command>peflags</command> tool
from the <literal>rebase</literal> package can be used to set the large
address awareness flag in the executable file header.
</para></listitem>

<listitem><para>
The registry setting "heap_chunk_in_mb" has been removed, in favor of a new
per-executable setting in the executable file header which can be set using the
<command>peflags</command> tool.  See <xref linkend="setup-maxmem"></xref>
for more information.
</para></listitem>

<listitem><para>
The CYGWIN=tty mode using pipes to communicate with the console in a pseudo
tty-like mode has been removed.  Either just use the normal Windows console
as is, or use a terminal application like <command>mintty</command>.
</para></listitem>

<listitem><para>
New <command>getconf</command> command for querying confstr(3), pathconf(3),
sysconf(3), and limits.h configuration.
</para></listitem>

<listitem><para>
New <command>tzset</command> utility to generate a POSIX-compatible TZ
environment variable from the Windows timezone settings.
</para></listitem>

<listitem><para>
The passwd command now allows an administrator to use the -R command for
other user accounts:  passwd -R username.
</para></listitem>

<listitem><para>
Pthread spinlocks.  New APIs: pthread_spin_destroy, pthread_spin_init,
pthread_spin_lock, pthread_spin_trylock, pthread_spin_unlock.
</para></listitem>

<listitem><para>
Pthread stack address management.  New APIs: pthread_attr_getstack,
pthread_attr_getstackaddr, pthread_attr_getguardsize, pthread_attr_setstack,
pthread_attr_setstackaddr, pthread_attr_setguardsize, pthread_getattr_np.
</para></listitem>

<listitem><para>
POSIX Clock Selection option.  New APIs: clock_nanosleep,
pthread_condattr_getclock, pthread_condattr_setclock.
</para></listitem>

<listitem><para>
clock_gettime(3) and clock_getres(3) accept per-process and per-thread CPU-time
clocks, including CLOCK_PROCESS_CPUTIME_ID and CLOCK_THREAD_CPUTIME_ID.
New APIs: clock_getcpuclockid, pthread_getcpuclockid.
</para></listitem>

<listitem><para>
GNU/glibc error.h error reporting functions.  New APIs: error, error_at_line.
New exports: error_message_count, error_one_per_line, error_print_progname.
Also, perror and strerror_r no longer clobber strerror storage.
</para></listitem>

<listitem><para>
C99 &lt;tgmath.h&gt; type-generic macros.
</para></listitem>

<listitem><para>
/proc/loadavg now shows the number of currently running processes and the
total number of processes.
</para></listitem>

<listitem><para>
Added /proc/devices and /proc/misc, which lists supported device types and
their device numbers.
</para></listitem>

<listitem><para>
Added /proc/swaps, which shows the location and size of Windows paging file(s).
</para></listitem>

<listitem><para>
Added /proc/sysvipc/msg, /proc/sysvipc/sem, and /proc/sysvipc/shm which
provide information about System V IPC message queues, semaphores, and
shared memory.
</para></listitem>

<listitem><para>
/proc/version now shows the username of whomever compiled the Cygwin DLL
as well as the version of GCC used when compiling.
</para></listitem>

<listitem><para>
dlopen now supports the Glibc-specific RTLD_NODELETE and RTLD_NOOPEN flags.
</para></listitem>

<listitem><para>
The printf(3) and wprintf(3) families of functions now handle the %m
conversion flag.
</para></listitem>

<listitem><para>
Other new API: clock_settime, __fpurge, getgrouplist, get_current_dir_name,
getpt, ppoll, psiginfo, psignal, ptsname_r, sys_siglist, pthread_setschedprio,
pthread_sigqueue, sysinfo.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.9"><title>What's new and what changed in 1.7.9</title>

<itemizedlist mark="bullet">

<listitem><para>
New API: strchrnul.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.8"><title>What's new and what changed in 1.7.8</title>

<itemizedlist mark="bullet">

<listitem><para>
Drop support for Windows NT4 prior to Service Pack 4.
</para></listitem>

<listitem><para>
Reinstantiate Cygwin's ability to delete an empty directory which is the
current working directory of the same or another process.  Same for any
other empty directory which has been opened by the same or another process.
</para></listitem>

<listitem><para>
Cygwin now ships the C standard library fenv.h header file, and implements the
related APIs (including GNU/glibc extensions): feclearexcept, fedisableexcept,
feenableexcept, fegetenv, fegetexcept, fegetexceptflag, fegetprec, fegetround,
feholdexcept, feraiseexcept, fesetenv, fesetexceptflag, fesetprec, fesetround,
fetestexcept, feupdateenv, and predefines both default and no-mask FP
environments.  See the
<ulink url="http://www.gnu.org/software/libc/manual/html_node/Arithmetic.html">
GNU C Library manual</ulink> for full details of this functionality.
</para></listitem>

<listitem><para>
Support for the C99 complex functions, except for the "long double"
implementations.  New APIs: cacos, cacosf, cacosh, cacoshf, carg, cargf, casin,
casinf, casinh, casinhf, catan, catanf, catanh, catanhf, ccos, ccosf, ccosh,
ccoshf, cexp, cexpf, cimag, cimagf, clog, clogf, conj, conjf, cpow, cpowf,
cproj, cprojf, creal, crealf, csin, csinf, csinh, csinhf, csqrt, csqrtf, ctan,
ctanf, ctanh, ctanhf.
</para></listitem>

<listitem><para>
Fix the width of "CJK Ambiguous Width" characters to 1 for singlebyte charsets
and 2 for East Asian multibyte charsets. (For UTF-8, it remains dependent on
the specified language, and the "@cjknarrow" locale modifier can still be used
to force width 1.)
</para></listitem>

<listitem><para>
The strerror_r interface now has two flavors; if _GNU_SOURCE is
defined, it retains the previous behavior of returning char *
(but the result is now guaranteed to be NUL-terminated); otherwise
it now obeys POSIX semantics of returning int.
</para></listitem>

<listitem><para>
/proc/sys now allows unfiltered access to the native NT namespace.  Access
restrictions still apply.  Direct device access via /proc/sys is not yet
supported.  File system access via block devices works.  For instance
(note the trailing slash!)
<screen>
bash$ cd /proc/sys/Device/HarddiskVolumeShadowCopy1/
</screen>
</para></listitem>

<listitem><para>
Other new APIs: llround, llroundf, madvise, pthread_yield.
Export program_invocation_name, program_invocation_short_name.
Support TIOCGPGRP, TIOCSPGRP ioctls.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.7"><title>What's new and what changed in 1.7.7</title>

<itemizedlist mark="bullet">

<listitem><para>
Partially revert the 1.7.6 change to set the Win32 current working directory
(CWD) always to an invalid directory, since it breaks backward compatibility
too much.  The Cygwin CWD and the Win32 CWD are now kept in sync again, unless
the Cygwin CWD is not usable as Win32 CWD.  See the reworked
<xref linkend="pathnames-win32-api"></xref> for details.
</para></listitem>

<listitem><para>
Make sure to follow the Microsoft security advisory concerning DLL hijacking.
See the <ulink url="http://www.microsoft.com/technet/security/advisory/2269637.mspx">Microsoft Security Advisory (2269637) "Insecure Library Loading Could Allow Remote Code Execution"</ulink> for details.
</para></listitem>

<listitem><para>
Allow to link against -lbinmode instead of /lib/binmode.o.  Same for
-ltextmode, -ltextreadmode and -lautomode. 
See <xref linkend="textbin-devel"></xref> for details.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.6"><title>What's new and what changed in 1.7.6</title>

<itemizedlist mark="bullet">

<listitem><para>
Add new mount options "dos" and "ihash" to allow overriding Cygwin default
behaviour on broken filesystems not recognized by Cygwin.
</para></listitem>

<listitem><para>
Add new mount option "bind" to allow remounting parts of the POSIX file
hirarchy somewhere else.
</para></listitem>

<listitem><para>
Ttys and ptys are handled as securable objects using file-like permissions
and owner/group information.  <command>chmod</command> and
<command>chown</command> now work on ttys/ptys.  A new mechanism is used
to propagate pty handles safely to other processes, which does not require
to use Cygserver.
</para></listitem>

<listitem><para>
Pass on coresize settings made with setrlimit(2).  This allows shells to
disable creating stackdump files in child processes via
<screen>ulimit -c 0</screen> in bash or <screen>limit coredumpsize 0</screen>
in tcsh.
</para></listitem>

<listitem><para>
Locale categories contain all localization strings additionally as wide-char
strings.  locale(1) prints these values just as on Linux.  nl_langinfo(3)
allows to fetch them.
</para></listitem>

<listitem><para>
New interfaces mkostemp(3) and mkostemps(3) are added.
</para></listitem>

<listitem><para>
New virtual file /proc/filesystems.
</para></listitem>

<listitem><para>
clock_gettime(3) and clock_getres(3) accept CLOCK_MONOTONIC.
</para></listitem>

<listitem><para>
DEPRECATED with 1.7.7: Cygwin handles the current working directory entirely
on its own.  The Win32 current working directory is set to an invalid path to
be out of the way.  [...]
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.5"><title>What's new and what changed in 1.7.5</title>

<itemizedlist mark="bullet">

<listitem><para>
Support for DEC Backarrow Key Mode escape sequences (ESC [ ? 67 h, ESC [ ? 67 l)
in Windows console.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.3"><title>What's new and what changed in 1.7.3</title>

<itemizedlist mark="bullet">

<listitem><para>
Support for GB2312/EUC-CN.  These charsets are implemented as aliases to GBK.
GB2312 is now the default charset name for the locales zh_CN and zh_SG, just
as on Linux.
</para></listitem>

<listitem><para>
Modification and access timestamps of devices reflect the current time.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.2"><title>What's new and what changed in 1.7.2</title>

<itemizedlist mark="bullet">

<listitem><para>Localization support has been much improved.</para>

  <itemizedlist mark="bullet">

  <listitem><para>
  Cygwin now handles locales using the underlying Windows locale
  support.  The locale must exist in Windows to be recognized.
  Locale aliases from the file /usr/share/locale/locale.alias are also
  allowed, as long as their replacement is supported by the underlying Windows.
  </para></listitem>

  <listitem><para>
  New tool "locale" to fetch locale information and default locales based on
  the Windows default settings as well as lists of all supported locales
  and character sets.
  </para></listitem>

  <listitem><para>
  Default charset for locales without explicit charset is now chosen
  from a list of Linux-compatible charsets.
  </para>
  
  <para>
  For instance: en_US -> ISO-8859-1, ja_JP -> EUC-JP, zh_TW -> Big5.
  </para></listitem>

  <listitem><para>
  Added support for the charsets GEORGIAN-PS, PT154, and TIS-620.
  </para></listitem>

  <listitem><para>
  Support for the various locale modifiers to switch charsets as on Linux.
  </para></listitem>

  <listitem><para>
  Default charset in the "C" or "POSIX" locale has been changed back
  from UTF-8 to ASCII, to avoid problems with applications
  expecting a singlebyte charset in the "C"/"POSIX" locale.  Still use
  UTF-8 internally for filename conversion in this case.
  </para></listitem>

  <listitem><para>
  LC_COLLATE, LC_MONETARY, LC_NUMERIC, and LC_TIME localization is
  enabled via Windows locale support.  LC_MESSAGES is enabled via a big
  table with localized strings.
  </para></listitem>

  <listitem><para>
  fnmatch(3), regcomp(3), regexec(3) calls are now multibyte-aware.
  </para></listitem>

  <listitem><para>
  printf(3), wprintf(3) families of functions now handle the grouping
  flag, the apostrophe <literal>'</literal>, per POSIX-1.2008.  The
  integer portion of the result of a decimal conversion (%i, %d, %u, %f,
  %F, %g, %G) will be formatted with thousands' grouping characters.
  </para></listitem>

  <listitem><para>
  strftime(3), wcsftime(3), and strptime(3) now handle the E and O format
  modifiers to print/scan alternative date and time representations or to
  use alternative digits in locales which support this.  Additionally these
  functions now also support the padding modifiers '0' and '+', as well as
  a field width per POSIX-1.2008.
  </para></listitem>

  <listitem><para>
  New strfmon(3) call.
  </para></listitem>

  </itemizedlist>

</listitem>

<listitem><para>
Support open(2) flags O_CLOEXEC and O_TTY_INIT flags.  Support fcntl
flag F_DUPFD_CLOEXEC.  Support socket flags SOCK_CLOEXEC and SOCK_NONBLOCK.
Add new Linux-compatible API calls accept4(2), dup3(2), and pipe2(2).
Support the signal SIGPWR.
</para></listitem>

<listitem><para>Enhanced Windows console support.</para>

  <itemizedlist mark="bullet">

  <listitem><para>
  The console's backspace keycode can be changed using 'stty erase'.
  </para></listitem>

  <listitem><para>
  Function keys send distinguished escape sequences compatible with rxvt.
  Keypad keys send distinguished escape sequences, xterm-style.
  </para></listitem>

  <listitem><para>
  Support of combining Alt and AltGr modifiers in console window
  (compatible with xterm and mintty), so that e.g. Alt-@ sends ESC @
  also on keyboards where @ is mapped to an AltGr combination.
  </para></listitem>

  <listitem><para>
  Report mouse wheel scroll events in mouse reporting mode 1000 (note:
  this doesn't seem to work on all systems, assumedly due to driver
  interworking issues).
  Add mouse reporting mode 1002 to report mouse drag movement.
  Add mouse reporting mode 1003 to report any mouse movement.
  Add focus event reporting (mode 1004), compatible with xterm and mintty.
  </para></listitem>

  <listitem><para>
  Add escape sequences for not bold (22), not invisible (28), not
  blinking (25) (compatible with xterm and mintty).
  </para></listitem>

  <listitem><para>
  Support VT100 line drawing graphics mode in console window (compatible
  with xterm and mintty).
  </para></listitem>

  </itemizedlist>

</listitem>

<listitem><para>
Handle native DOS paths always as if mounted with "posix=0,noacl".
</para></listitem>

<listitem><para>
Handle UNC paths starting with slashes identical to /cygdrive paths.
In other words, use the /cygdrive mount flags for these paths as well.
</para></listitem>

<listitem><para>
Recognize NWFS filesystem and workaround broken OS call.
</para></listitem>

<listitem><para>
New support for eXtensible Data Record (XDR) encoding and decoding,
as defined by RFCs 1014, 1832, and 4506.  The XDR protocol and
functions are useful for cross-platfrom data exchange, and are
commonly used as the core data interchange format for Remote
Procedure Call (RPC) and NFS.
</para></listitem>

</itemizedlist>

</sect2>

<sect2 id="ov-new1.7.1"><title>What's new and what changed from 1.5 to 1.7</title>

<sect3 id="ov-new1.7-os"><title>OS related changes</title>

<itemizedlist mark="bullet">

<listitem><para>
Windows 95, 98 and Me are not supported anymore.  The new Cygwin 1.7 DLL
will not run on any of these systems.
</para></listitem>

<listitem><para>
Add support for Windows 7 and Windows Server 2008 R2.
</para></listitem>

</itemizedlist>

</sect3>

<sect3 id="ov-new1.7-file"><title>File Access related changes</title>

<itemizedlist mark="bullet">

<listitem><para>
Mount points are no longer stored in the registry.  Use /etc/fstab and
/etc/fstab.d/$USER instead.  Mount points created with mount(1) are only
local to the current session and disappear when the last Cygwin process
in the session exits.
</para></listitem>

<listitem><para>
Cygwin creates the mount points for /, /usr/bin, and /usr/lib
automatically from it's own position on the disk.  They don't have to be
specified in /etc/fstab.
</para></listitem>

<listitem><para>
If a filename cannot be represented in the current character set, the
character will be converted to a sequence Ctrl-X + UTF-8 representation
of the character.  This allows to access all files, even those not
having a valid representation of their filename in the current character
set.  To always have a valid string, use the UTF-8 charset by
setting the environment variable $LANG, $LC_ALL, or $LC_CTYPE to a valid
POSIX value, such as "en_US.UTF-8".
</para></listitem>

<listitem><para>
PATH_MAX is now 4096.  Internally, path names can be as long as the
underlying OS can handle (32K).
</para></listitem>

<listitem><para>
struct dirent now supports d_type, filled out with DT_REG or DT_DIR.
All other file types return as DT_UNKNOWN for performance reasons.
</para></listitem>

<listitem><para>
The CYGWIN environment variable options "ntsec" and "smbntsec" have been
replaced by the per-mount option "acl"/"noacl".
</para></listitem>

<listitem><para>
The CYGWIN environment variable option "ntea" has been removed without
substitute.
</para></listitem>

<listitem><para>
The CYGWIN environment variable option "check_case" has been removed in
favor of real case-sensitivity on file systems supporting it.
</para></listitem>

<listitem><para>
Creating filenames with special DOS characters '"', '*', ':', '&lt;',
'&gt;', '|' is supported.
</para></listitem>

<listitem><para>
Creating files with special DOS device filename components ("aux",
"nul", "prn") is supported.
</para></listitem>

<listitem><para>
File names are case sensitive if the OS and the underlying file system
supports it.  Works on NTFS and NFS.  Does not work on FAT and Samba
shares.  Requires to change a registry key (see the User's Guide).  Can
be switched off on a per-mount basis.
</para></listitem>

<listitem><para>
Due to the above changes, managed mounts have been removed.
</para></listitem>

<listitem><para>
Incoming DOS paths are always handled case-insensitive and get no POSIX
permission, as if they are mounted with noacl,posix=0 mount flags.
</para></listitem>

<listitem><para>
unlink(2) and rmdir(2) try very hard to remove files/directories even if
they are currently accessed or locked.  This is done by utilizing the
hidden recycle bin directories and marking the files for deletion.
</para></listitem>

<listitem><para>
rename(2) rewritten to be more POSIX conformant.
</para></listitem>

<listitem><para>
access(2) now performs checks using the real user ID, as required by
POSIX; the old behavior of querying based on effective user ID is
available through the new faccessat(2) and euidaccess(2) APIs.
</para></listitem>

<listitem><para>
Add st_birthtim member to struct stat.
</para></listitem>

<listitem><para>
File locking is now advisory, not mandatory anymore.  The fcntl(2) and
the new lockf(2) APIs create and maintain locks with POSIX semantics,
the flock(2) API creates and maintains locks with BSD semantics.  POSIX
and BSD locks are independent of each other.
</para></listitem>

<listitem><para>
Implement atomic O_APPEND mode.
</para></listitem>

<listitem><para>
New open(2) flags O_DIRECTORY, O_EXEC and O_SEARCH.
</para></listitem>

<listitem><para>
Make the "plain file with SYSTEM attribute set" style symlink default
again when creating symlinks.  Only create Windows shortcut style
symlinks if CYGWIN=winsymlinks is set in the environment.
</para></listitem>

<listitem><para>
Symlinks now use UTF-16 encoding for the target filename for better
internationalization support.  Cygwin 1.7 can read all old style
symlinks, but the new style is not compatible with older Cygwin
releases.
</para></listitem>

<listitem><para>
Handle NTFS native symlinks available since Vista/2008 as symlinks (but
don't create Vista/2008 symlinks due to unfortunate OS restrictions).
</para></listitem>

<listitem><para>
Recognize NFS shares and handle them using native mechanisms.  Recognize
and create real symlinks on NFS shares.  Get correct stat(2) information
and set real mode bits on open(2), mkdir(2) and chmod(2).
</para></listitem>

<listitem><para>
Recognize MVFS and workaround problems manipulating metadata and handling
DOS attributes.
</para></listitem>

<listitem><para>
Recognize Netapp DataOnTap drives and fix inode number handling.
</para></listitem>

<listitem><para>
Recognize Samba version beginning with Samba 3.0.28a using the new
extended version information negotiated with the Samba developers.
</para></listitem>

<listitem><para>
Stop faking hardlinks by copying the file on filesystems which don't
support hardlinks natively (FAT, FAT32, etc.).  Just return an error
instead, just like Linux.
</para></listitem>

<listitem><para>
List servers of all accessible domains and workgroups in // instead of
just the servers in the own domain/workgroup.
</para></listitem>

<listitem><para>
Support Linux-like extended attributes ([fl]getxattr, [fl]listxattr,
[fl]setxattr, [fl]removexattr).
</para></listitem>

<listitem><para>
New file conversion API for conversion from Win32 to POSIX path and vice
versa (cygwin_conv_path, cygwin_create_path, cygwin_conv_path_list).
</para></listitem>

<listitem><para>
New openat family of functions: openat, faccessat, fchmodat, fchownat,
fstatat, futimesat, linkat, mkdirat, mkfifoat, mknodat, readlinkat,
renameat, symlinkat, unlinkat.
</para></listitem>

<listitem><para>
Other new APIs: posix_fadvise, posix_fallocate, funopen, fopencookie,
open_memstream, open_wmemstream, fmemopen, fdopendir, fpurge, mkstemps,
eaccess, euidaccess, canonicalize_file_name, fexecve, execvpe.
</para></listitem>

</itemizedlist>

</sect3>

<sect3 id="ov-new1.7-net"><title>Network related changes</title>

<itemizedlist mark="bullet">

<listitem><para>
New implementation for blocking sockets and select on sockets which is
supposed to allow POSIX-compatible sharing of sockets between threads
and processes.
</para></listitem>

<listitem><para>
send/sendto/sendmsg now send data in 64K chunks to circumvent an
internal buffer problem in WinSock (KB 201213).
</para></listitem>

<listitem><para>
New send/recv option MSG_DONTWAIT.
</para></listitem>

<listitem><para>
IPv6 support.  New APIs getaddrinfo, getnameinfo, freeaddrinfo,
gai_strerror, in6addr_any, in6addr_loopback.  On IPv6-less systems,
replacement functions are available for IPv4.  On systems with IPv6
enabled, the underlying WinSock functions are used.  While I tried hard
to get the functionality as POSIXy as possible, keep in mind that a
*fully* conformant implementation of getaddrinfo and other stuff is only
available starting with Windows Vista/2008.
</para></listitem>

<listitem><para>
Resolver functions (res_init, res_query, res_search, res_querydomain,
res_mkquery, res_send, dn_comp, dn_expand) are now part of Cygwin.
Applications don't have to link against minires anymore.  Actually, this
*is* the former libminires.a.
</para></listitem>

<listitem><para>
rcmd is now implemented inside of Cygwin, instead of calling the WinSock
function.  This allows rsh(1) usage on Vista/2008 and later, which
dropped this function from WinSock.
</para></listitem>

<listitem><para>
Define multicast structures in netinet/in.h.  Note that fully conformant
multicast support is only available beginning with Vista/2008.
</para></listitem>

<listitem><para>
Improve get_ifconf.  Redefine struct ifreq and subsequent datastructures
to be able to keep more information.  Support SIOCGIFINDEX,
SIOCGIFDSTADDR and the Cygwin specific SIOCGIFFRNDLYNAM.  Support real
interface flags on systems supporting them.
</para></listitem>

<listitem><para>
Other new APIs: bindresvport, bindresvport_sa, gethostbyname2,
iruserok_sa, rcmd_af, rresvport_af.  getifaddrs, freeifaddrs,
if_nametoindex, if_indextoname, if_nameindex, if_freenameindex.
</para></listitem>

<listitem><para>
Add /proc/net/if_inet6.
</para></listitem>

</itemizedlist>

</sect3>

<sect3 id="ov-new1.7-device"><title>Device related changes</title>

<itemizedlist mark="bullet">

<listitem><para>
Reworked pipe implementation which uses overlapped IO to create more
reliable interruptible pipes and fifos.
</para></listitem>

<listitem><para>
The CYGWIN environment variable option "binmode" has been removed.
</para></listitem>

<listitem><para>
Improved fifo handling by using native Windows named pipes.
</para></listitem>

<listitem><para>
Detect when a stdin/stdout which looks like a pipe is really a tty.
Among other things, this allows a debugged application to recognize that
it is using the same tty as the debugger.
</para></listitem>

<listitem><para>
Support UTF-8 in console window.
</para></listitem>

<listitem><para>
In the console window the backspace key now emits DEL (0x7f) instead of
BS (0x08), Alt-Backspace emits ESC-DEL (0x1b,0x7f) instead of DEL
(0x7f), same as the Linux console and xterm.  Control-Space now emits an
ASCII NUL (0x0) character.
</para></listitem>

<listitem><para>
Support up to 64 serial interfaces using /dev/ttyS0 - /dev/ttyS63.
</para></listitem>

<listitem><para>
Support up to 128 raw disk drives /dev/sda - /dev/sddx.
</para></listitem>

<listitem><para>
New API: cfmakeraw, get_avphys_pages, get_nprocs, get_nprocs_conf,
get_phys_pages, posix_openpt.
</para></listitem>

</itemizedlist>

</sect3>

<sect3 id="ov-new1.7-posix"><title>Other POSIX related changes</title>

<itemizedlist mark="bullet">

<listitem><para>
A lot of character sets are supported now via a call to setlocale().
The setting of the environment variables $LANG, $LC_ALL or $LC_CTYPE
will be used.  For instance, setting $LANG to "de_DE.ISO-8859-15" before
starting a Cygwin session will use the ISO-8859-15 character set in the
entire session.  The default locale in the absence of one of the
aforementioned environment variables is "C.UTF-8".
</para>

<para>
The full list of supported character sets: "ASCII", "ISO-8859-x" with x
in 1-16, except 12, "UTF-8", Windows codepages "CPxxx", with xxx in
(437, 720, 737, 775, 850, 852, 855, 857, 858, 862, 866, 874, 1125, 1250,
1251, 1252, 1253, 1254, 1255, 1256, 1257, 1258), "KOI8-R", "KOI8-U",
"SJIS", "GBK", "eucJP", "eucKR", and "Big5".
</para>

</listitem>

<listitem><para>
Allow multiple concurrent read locks per thread for pthread_rwlock_t.
</para></listitem>

<listitem><para>
Implement pthread_kill(thread, 0) as per POSIX.
</para></listitem>

<listitem><para>
New API for POSIX IPC: Named semaphores: sem_open, sem_close,
sem_unlink.  Message queues: mq_open, mq_getattr, mq_setattr, mq_notify,
mq_send, mq_timedsend, mq_receive, mq_timedreceive, mq_close, mq_unlink.
Shared memory: shm_open, shm_unlink.
</para></listitem>

<listitem><para>
Only declare expected functions in &lt;strings.h&gt;, don't include
&lt;string.h&gt; from here.
</para></listitem>

<listitem><para>
Support for WCONTINUED, WIFCONTINUED() added to waitpid and wait4.
</para></listitem>

<listitem><para>
New APIs: _Exit, confstr, insque, remque, sys_sigabbrev, posix_madvise,
posix_memalign, reallocf, exp10, exp10f, pow10, pow10f, lrint, lrintf,
rint, rintf, llrint, llrintf, llrintl, lrintl, rintl, mbsnrtowcs,
strcasestr, stpcpy, stpncpy, wcpcpy, wcpncpy, wcsnlen, wcsnrtombs,
wcsftime, wcstod, wcstof, wcstoimax, wcstok, wcstol, wcstoll, wcstoul,
wcstoull, wcstoumax, wcsxfrm, wcscasecmp, wcsncasecmp, fgetwc, fgetws,
fputwc, fputws, fwide, getwc, getwchar, putwc, putwchar, ungetwc,
asnprintf, dprintf, vasnprintf, vdprintf, wprintf, fwprintf, swprintf,
vwprintf, vfwprintf, vswprintf, wscanf, fwscanf, swscanf, vwscanf,
vfwscanf, vswscanf.
</para></listitem>

</itemizedlist>

</sect3>

<sect3 id="ov-new1.7-sec"><title>Security related changes</title>

<itemizedlist mark="bullet">

<listitem><para>
Getting a domain user's groups is hopefully more bulletproof now.
</para></listitem>

<listitem><para>
Cygwin now comes with a real LSA authentication package.  This must be
manually installed by a privileged user using the /bin/cyglsa-config
script.  The advantages and disadvantages are noted in
https://cygwin.com/ml/cygwin-developers/2006-11/msg00000.html
</para></listitem>

<listitem><para>
Cygwin now allows storage and use of user passwords in a hidden area of
the registry.  This is tried first when Cygwin is called by privileged
processes to switch the user context.  This allows, for instance, ssh
public key sessions with full network credentials to access shares on
other machines.
</para></listitem>

<listitem><para>
New options have been added to the mkpasswd and mkgroup tools to ease
use in multi-machine and multi-domain environments.  The existing
options have a slightly changed behaviour.
</para></listitem>

</itemizedlist>

</sect3>

<sect3 id="ov-new1.7-misc"><title>Miscellaneous</title>

<itemizedlist mark="bullet">

<listitem><para>
New ldd utility, similar to Linux.
</para></listitem>

<listitem><para>
New link libraries libdl.a, libresolv.a, librt.a.
</para></listitem>

<listitem><para>
Fallout from the long path names: If the current working directory is
longer than 260 bytes, or if the current working directory is a virtual
path (like /proc, /cygdrive, //server), don't call native Win32 programs
since they don't understand these paths.
</para></listitem>

<listitem><para>
On the first usage of a DOS path (C:\foo, \\foo\bar), the Cygwin DLL
emits a scary warning that DOS paths shouldn't be used.  This warning
may be disabled via the new CYGWIN=nodosfilewarning setting.
</para></listitem>

<listitem><para>
The CYGWIN environment variable option "server" has been removed.
Cygwin automatically uses cygserver if it's available.
</para></listitem>

<listitem><para>
Allow environment of arbitrary size instead of a maximum of 32K.
</para></listitem>

<listitem><para>
Don't force uppercase environment when started from a non-Cygwin
process.  Except for certain Windows and POSIX variables which are
always uppercased, preserve environment case.  Switch back to old
behaviour with the new CYGWIN=upcaseenv setting.
</para></listitem>

<listitem><para>
Detect and report a missing DLL on process startup.
</para></listitem>

<listitem><para>
Add /proc/registry32 and /proc/registry64 paths to access 32 bit and 64
bit registry on 64 bit systems.
</para></listitem>

<listitem><para>
Add the ability to distinguish registry keys and registry values with
the same name in the same registry subtree.  The key is called "foo" and
the value will be called "foo%val" in this case.
</para></listitem>

<listitem><para>
Align /proc/cpuinfo more closly to Linux content.
</para></listitem>

<listitem><para>
Add /proc/$PID/mounts entries and a symlink /proc/mounts pointing to
/proc/self/mounts as on Linux.
</para></listitem>

<listitem><para>
Optimized strstr and memmem implementation.
</para></listitem>

<listitem><para>
Remove backwards compatibility with old signal masks.  (Some *very* old
programs which use signal masks may no longer work correctly).
</para></listitem>

<listitem><para>
Cygwin now exports wrapper functions for libstdc++ operators new and
delete, to support the toolchain in implementing full C++ standards
conformance when working with shared libraries.
</para></listitem>

<listitem><para>
Different Cygwin installations in different paths can be run in parallel
without knowing of each other.  The path of the Cygwin DLL used in a
process is a key used when creating IPC objects.  So different Cygwin
DLLs are running in different namespaces.
</para></listitem>

<listitem><para>
Each Cygwin DLL stores its path and installation key in the registry.
This allows troubleshooting of problems which could be a result of
having multiple concurrent Cygwin installations.
</para></listitem>

</itemizedlist>

</sect3>

</sect2>

</sect1>