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.\" ========================================================================
.\"
.IX Title "PERLCYGWIN 1"
.TH PERLCYGWIN 1 "2018-03-01" "perl v5.26.3" "Perl Programmers Reference Guide"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
perlcygwin \- Perl for Cygwin
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
This document will help you configure, make, test and install Perl
on Cygwin.  This document also describes features of Cygwin that will
affect how Perl behaves at runtime.
.PP
\&\fB\s-1NOTE:\s0\fR There are pre-built Perl packages available for Cygwin and a
version of Perl is provided in the normal Cygwin install.  If you do
not need to customize the configuration, consider using one of those
packages.
.SH "PREREQUISITES FOR COMPILING PERL ON CYGWIN"
.IX Header "PREREQUISITES FOR COMPILING PERL ON CYGWIN"
.SS "Cygwin = GNU+Cygnus+Windows (Don't leave \s-1UNIX\s0 without it)"
.IX Subsection "Cygwin = GNU+Cygnus+Windows (Don't leave UNIX without it)"
The Cygwin tools are ports of the popular \s-1GNU\s0 development tools for Win32
platforms.  They run thanks to the Cygwin library which provides the \s-1UNIX\s0
system calls and environment these programs expect.  More information
about this project can be found at:
.PP
<http://www.cygwin.com/>
.PP
A recent net or commercial release of Cygwin is required.
.PP
At the time this document was last updated, Cygwin 1.7.16 was current.
.SS "Cygwin Configuration"
.IX Subsection "Cygwin Configuration"
While building Perl some changes may be necessary to your Cygwin setup so
that Perl builds cleanly.  These changes are \fBnot\fR required for normal
Perl usage.
.PP
\&\fB\s-1NOTE:\s0\fR The binaries that are built will run on all Win32 versions.
They do not depend on your host system (WinXP/Win2K/Win7) or your
Cygwin configuration (binary/text mounts, cvgserver).
The only dependencies come from hard-coded pathnames like \fI/usr/local\fR.
However, your host system and Cygwin configuration will affect Perl's
runtime behavior (see \*(L"\s-1TEST\*(R"\s0).
.IP "\(bu" 4
\&\f(CW\*(C`PATH\*(C'\fR
.Sp
Set the \f(CW\*(C`PATH\*(C'\fR environment variable so that Configure finds the Cygwin
versions of programs. Any not-needed Windows directories should be removed or
moved to the end of your \f(CW\*(C`PATH\*(C'\fR.
.IP "\(bu" 4
\&\fInroff\fR
.Sp
If you do not have \fInroff\fR (which is part of the \fIgroff\fR package),
Configure will \fBnot\fR prompt you to install \fIman\fR pages.
.SH "CONFIGURE PERL ON CYGWIN"
.IX Header "CONFIGURE PERL ON CYGWIN"
The default options gathered by Configure with the assistance of
\&\fIhints/cygwin.sh\fR will build a Perl that supports dynamic loading
(which requires a shared \fIcygperl5_16.dll\fR).
.PP
This will run Configure and keep a record:
.PP
.Vb 1
\&  ./Configure 2>&1 | tee log.configure
.Ve
.PP
If you are willing to accept all the defaults run Configure with \fB\-de\fR.
However, several useful customizations are available.
.SS "Stripping Perl Binaries on Cygwin"
.IX Subsection "Stripping Perl Binaries on Cygwin"
It is possible to strip the EXEs and DLLs created by the build process.
The resulting binaries will be significantly smaller.  If you want the
binaries to be stripped, you can either add a \fB\-s\fR option when Configure
prompts you,
.PP
.Vb 5
\&  Any additional ld flags (NOT including libraries)? [none] \-s
\&  Any special flags to pass to g++ to create a dynamically loaded
\&  library?
\&  [none] \-s
\&  Any special flags to pass to gcc to use dynamic linking? [none] \-s
.Ve
.PP
or you can edit \fIhints/cygwin.sh\fR and uncomment the relevant variables
near the end of the file.
.SS "Optional Libraries for Perl on Cygwin"
.IX Subsection "Optional Libraries for Perl on Cygwin"
Several Perl functions and modules depend on the existence of
some optional libraries.  Configure will find them if they are
installed in one of the directories listed as being used for library
searches.  Pre-built packages for most of these are available from
the Cygwin installer.
.IP "\(bu" 4
\&\f(CW\*(C`\-lcrypt\*(C'\fR
.Sp
The crypt package distributed with Cygwin is a Linux compatible 56\-bit
\&\s-1DES\s0 crypt port by Corinna Vinschen.
.Sp
Alternatively, the crypt libraries in \s-1GNU\s0 libc have been ported to Cygwin.
.Sp
As of libcrypt 1.3 (March 2016), you will need to install the
libcrypt-devel package for Configure to detect \fIcrypt()\fR.
.IP "\(bu" 4
\&\f(CW\*(C`\-lgdbm_compat\*(C'\fR (\f(CW\*(C`use GDBM_File\*(C'\fR)
.Sp
\&\s-1GDBM\s0 is available for Cygwin.
.Sp
\&\s-1NOTE:\s0 The \s-1GDBM\s0 library only works on \s-1NTFS\s0 partitions.
.IP "\(bu" 4
\&\f(CW\*(C`\-ldb\*(C'\fR (\f(CW\*(C`use DB_File\*(C'\fR)
.Sp
BerkeleyDB is available for Cygwin.
.Sp
\&\s-1NOTE:\s0 The BerkeleyDB library only completely works on \s-1NTFS\s0 partitions.
.IP "\(bu" 4
\&\f(CW\*(C`cygserver\*(C'\fR (\f(CW\*(C`use IPC::SysV\*(C'\fR)
.Sp
A port of SysV \s-1IPC\s0 is available for Cygwin.
.Sp
\&\s-1NOTE:\s0 This has \fBnot\fR been extensively tested.  In particular,
\&\f(CW\*(C`d_semctl_semun\*(C'\fR is undefined because it fails a Configure test
and on Win9x the \fIshm*()\fR functions seem to hang.  It also creates
a compile time dependency because \fIperl.h\fR includes \fI<sys/ipc.h\fR>
and \fI<sys/sem.h\fR> (which will be required in the future when compiling
\&\s-1CPAN\s0 modules). \s-1CURRENTLY NOT SUPPORTED\s0!
.IP "\(bu" 4
\&\f(CW\*(C`\-lutil\*(C'\fR
.Sp
Included with the standard Cygwin netrelease is the inetutils package
which includes libutil.a.
.SS "Configure-time Options for Perl on Cygwin"
.IX Subsection "Configure-time Options for Perl on Cygwin"
The \fI\s-1INSTALL\s0\fR document describes several Configure-time options.  Some of
these will work with Cygwin, others are not yet possible.  Also, some of
these are experimental.  You can either select an option when Configure
prompts you or you can define (undefine) symbols on the command line.
.IP "\(bu" 4
\&\f(CW\*(C`\-Uusedl\*(C'\fR
.Sp
Undefining this symbol forces Perl to be compiled statically.
.IP "\(bu" 4
\&\f(CW\*(C`\-Dusemymalloc\*(C'\fR
.Sp
By default Perl does not use the \f(CW\*(C`malloc()\*(C'\fR included with the Perl source,
because it was slower and not entirely thread-safe.  If you want to force
Perl to build with the old \-Dusemymalloc define this.
.IP "\(bu" 4
\&\f(CW\*(C`\-Uuseperlio\*(C'\fR
.Sp
Undefining this symbol disables the PerlIO abstraction.  PerlIO is now the
default; it is not recommended to disable PerlIO.
.IP "\(bu" 4
\&\f(CW\*(C`\-Dusemultiplicity\*(C'\fR
.Sp
Multiplicity is required when embedding Perl in a C program and using
more than one interpreter instance.  This is only required when you build
a not-threaded perl with \f(CW\*(C`\-Uuseithreads\*(C'\fR.
.IP "\(bu" 4
\&\f(CW\*(C`\-Uuse64bitint\*(C'\fR
.Sp
By default Perl uses 64 bit integers.  If you want to use smaller 32 bit
integers, define this symbol.
.IP "\(bu" 4
\&\f(CW\*(C`\-Duselongdouble\*(C'\fR
.Sp
\&\fIgcc\fR supports long doubles (12 bytes).  However, several additional
long double math functions are necessary to use them within Perl
(\fI{atan2, cos, exp, floor, fmod, frexp, isnan, log, modf, pow, sin, sqrt}l,
strtold\fR).
These are \fBnot\fR yet available with newlib, the Cygwin libc.
.IP "\(bu" 4
\&\f(CW\*(C`\-Uuseithreads\*(C'\fR
.Sp
Define this symbol if you want not-threaded faster perl.
.IP "\(bu" 4
\&\f(CW\*(C`\-Duselargefiles\*(C'\fR
.Sp
Cygwin uses 64\-bit integers for internal size and position calculations,
this will be correctly detected and defined by Configure.
.IP "\(bu" 4
\&\f(CW\*(C`\-Dmksymlinks\*(C'\fR
.Sp
Use this to build perl outside of the source tree.  Details can be
found in the \fI\s-1INSTALL\s0\fR document.  This is the recommended way to
build perl from sources.
.SS "Suspicious Warnings on Cygwin"
.IX Subsection "Suspicious Warnings on Cygwin"
You may see some messages during Configure that seem suspicious.
.IP "\(bu" 4
Win9x and \f(CW\*(C`d_eofnblk\*(C'\fR
.Sp
Win9x does not correctly report \f(CW\*(C`EOF\*(C'\fR with a non-blocking read on a
closed pipe.  You will see the following messages:
.Sp
.Vb 2
\& But it also returns \-1 to signal EOF, so be careful!
\& WARNING: you can\*(Aqt distinguish between EOF and no data!
\&
\& *** WHOA THERE!!! ***
\&     The recommended value for $d_eofnblk on this machine was
\&     "define"!
\&     Keep the recommended value? [y]
.Ve
.Sp
At least for consistency with WinNT, you should keep the recommended
value.
.IP "\(bu" 4
Compiler/Preprocessor defines
.Sp
The following error occurs because of the Cygwin \f(CW\*(C`#define\*(C'\fR of
\&\f(CW\*(C`_LONG_DOUBLE\*(C'\fR:
.Sp
.Vb 2
\&  Guessing which symbols your C compiler and preprocessor define...
\&  try.c:<line#>: missing binary operator
.Ve
.Sp
This failure does not seem to cause any problems.  With older gcc
versions, \*(L"parse error\*(R" is reported instead of \*(L"missing binary
operator\*(R".
.SH "MAKE ON CYGWIN"
.IX Header "MAKE ON CYGWIN"
Simply run \fImake\fR and wait:
.PP
.Vb 1
\&  make 2>&1 | tee log.make
.Ve
.SH "TEST ON CYGWIN"
.IX Header "TEST ON CYGWIN"
There are two steps to running the test suite:
.PP
.Vb 1
\&  make test 2>&1 | tee log.make\-test
\&
\&  cd t; ./perl harness 2>&1 | tee ../log.harness
.Ve
.PP
The same tests are run both times, but more information is provided when
running as \f(CW\*(C`./perl harness\*(C'\fR.
.PP
Test results vary depending on your host system and your Cygwin
configuration.  If a test can pass in some Cygwin setup, it is always
attempted and explainable test failures are documented.  It is possible
for Perl to pass all the tests, but it is more likely that some tests
will fail for one of the reasons listed below.
.SS "File Permissions on Cygwin"
.IX Subsection "File Permissions on Cygwin"
\&\s-1UNIX\s0 file permissions are based on sets of mode bits for
{read,write,execute} for each {user,group,other}.  By default Cygwin
only tracks the Win32 read-only attribute represented as the \s-1UNIX\s0 file
user write bit (files are always readable, files are executable if they
have a \fI.{com,bat,exe}\fR extension or begin with \f(CW\*(C`#!\*(C'\fR, directories are
always readable and executable).  On WinNT with the \fIntea\fR \f(CW\*(C`CYGWIN\*(C'\fR
setting, the additional mode bits are stored as extended file attributes.
On WinNT with the default \fIntsec\fR \f(CW\*(C`CYGWIN\*(C'\fR setting, permissions use the
standard WinNT security descriptors and access control lists. Without one of
these options, these tests will fail (listing not updated yet):
.PP
.Vb 12
\&  Failed Test           List of failed
\&  \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-
\&  io/fs.t               5, 7, 9\-10
\&  lib/anydbm.t          2
\&  lib/db\-btree.t        20
\&  lib/db\-hash.t         16
\&  lib/db\-recno.t        18
\&  lib/gdbm.t            2
\&  lib/ndbm.t            2
\&  lib/odbm.t            2
\&  lib/sdbm.t            2
\&  op/stat.t             9, 20 (.tmp not an executable extension)
.Ve
.SS "NDBM_File and ODBM_File do not work on \s-1FAT\s0 filesystems"
.IX Subsection "NDBM_File and ODBM_File do not work on FAT filesystems"
Do not use NDBM_File or ODBM_File on \s-1FAT\s0 filesystem.  They can be
built on a \s-1FAT\s0 filesystem, but many tests will fail:
.PP
.Vb 6
\& ../ext/NDBM_File/ndbm.t       13  3328    71   59  83.10%  1\-2 4 16\-71
\& ../ext/ODBM_File/odbm.t      255 65280    ??   ??       %  ??
\& ../lib/AnyDBM_File.t           2   512    12    2  16.67%  1 4
\& ../lib/Memoize/t/errors.t      0   139    11    5  45.45%  7\-11
\& ../lib/Memoize/t/tie_ndbm.t   13  3328     4    4 100.00%  1\-4
\& run/fresh_perl.t                          97    1   1.03%  91
.Ve
.PP
If you intend to run only on \s-1FAT\s0 (or if using AnyDBM_File on \s-1FAT\s0),
run Configure with the \-Ui_ndbm and \-Ui_dbm options to prevent
NDBM_File and ODBM_File being built.
.PP
With \s-1NTFS\s0 (and no CYGWIN=nontsec), there should be no problems even if
perl was built on \s-1FAT.\s0
.ie n .SS """fork()"" failures in io_* tests"
.el .SS "\f(CWfork()\fP failures in io_* tests"
.IX Subsection "fork() failures in io_* tests"
A \f(CW\*(C`fork()\*(C'\fR failure may result in the following tests failing:
.PP
.Vb 3
\&  ext/IO/lib/IO/t/io_multihomed.t
\&  ext/IO/lib/IO/t/io_sock.t
\&  ext/IO/lib/IO/t/io_unix.t
.Ve
.PP
See comment on fork in \*(L"Miscellaneous\*(R" below.
.SH "Specific features of the Cygwin port"
.IX Header "Specific features of the Cygwin port"
.SS "Script Portability on Cygwin"
.IX Subsection "Script Portability on Cygwin"
Cygwin does an outstanding job of providing UNIX-like semantics on top of
Win32 systems.  However, in addition to the items noted above, there are
some differences that you should know about.  This is a very brief guide
to portability, more information can be found in the Cygwin documentation.
.IP "\(bu" 4
Pathnames
.Sp
Cygwin pathnames are separated by forward (\fI/\fR) slashes, Universal
Naming Codes (\fI//UNC\fR) are also supported Since cygwin\-1.7 non-POSIX
pathnames are discouraged.  Names may contain all printable
characters.
.Sp
File names are case insensitive, but case preserving.  A pathname that
contains a backslash or drive letter is a Win32 pathname, and not
subject to the translations applied to \s-1POSIX\s0 style pathnames, but
cygwin will warn you, so better convert them to \s-1POSIX.\s0
.Sp
For conversion we have \f(CW\*(C`Cygwin::win_to_posix_path()\*(C'\fR and
\&\f(CW\*(C`Cygwin::posix_to_win_path()\*(C'\fR.
.Sp
Since cygwin\-1.7 pathnames are \s-1UTF\-8\s0 encoded.
.IP "\(bu" 4
Text/Binary
.Sp
Since cygwin\-1.7 textmounts are deprecated and strongly discouraged.
.Sp
When a file is opened it is in either text or binary mode.  In text mode
a file is subject to CR/LF/Ctrl\-Z translations.  With Cygwin, the default
mode for an \f(CW\*(C`open()\*(C'\fR is determined by the mode of the mount that underlies
the file. See \*(L"Cygwin::is_binmount\*(R"(). Perl provides a \f(CW\*(C`binmode()\*(C'\fR function
to set binary mode on files that otherwise would be treated as text.
\&\f(CW\*(C`sysopen()\*(C'\fR with the \f(CW\*(C`O_TEXT\*(C'\fR flag sets text mode on files that otherwise
would be treated as binary:
.Sp
.Vb 1
\&    sysopen(FOO, "bar", O_WRONLY|O_CREAT|O_TEXT)
.Ve
.Sp
\&\f(CW\*(C`lseek()\*(C'\fR, \f(CW\*(C`tell()\*(C'\fR and \f(CW\*(C`sysseek()\*(C'\fR only work with files opened in binary
mode.
.Sp
The text/binary issue is covered at length in the Cygwin documentation.
.IP "\(bu" 4
PerlIO
.Sp
PerlIO overrides the default Cygwin Text/Binary behaviour.  A file will
always be treated as binary, regardless of the mode of the mount it lives
on, just like it is in \s-1UNIX.\s0  So \s-1CR/LF\s0 translation needs to be requested in
either the \f(CW\*(C`open()\*(C'\fR call like this:
.Sp
.Vb 1
\&  open(FH, ">:crlf", "out.txt");
.Ve
.Sp
which will do conversion from \s-1LF\s0 to \s-1CR/LF\s0 on the output, or in the
environment settings (add this to your .bashrc):
.Sp
.Vb 1
\&  export PERLIO=crlf
.Ve
.Sp
which will pull in the crlf PerlIO layer which does \s-1LF\s0 \-> \s-1CRLF\s0 conversion
on every output generated by perl.
.IP "\(bu" 4
\&\fI.exe\fR
.Sp
The Cygwin \f(CW\*(C`stat()\*(C'\fR, \f(CW\*(C`lstat()\*(C'\fR and \f(CW\*(C`readlink()\*(C'\fR functions make the \fI.exe\fR
extension transparent by looking for \fIfoo.exe\fR when you ask for \fIfoo\fR
(unless a \fIfoo\fR also exists).  Cygwin does not require a \fI.exe\fR
extension, but \fIgcc\fR adds it automatically when building a program.
However, when accessing an executable as a normal file (e.g., \fIcp\fR
in a makefile) the \fI.exe\fR is not transparent.  The \fIinstall\fR program
included with Cygwin automatically appends a \fI.exe\fR when necessary.
.IP "\(bu" 4
Cygwin vs. Windows process ids
.Sp
Cygwin processes have their own pid, which is different from the
underlying windows pid.  Most posix compliant Proc functions expect
the cygwin pid, but several Win32::Process functions expect the
winpid. E.g. \f(CW$$\fR is the cygwin pid of \fI/usr/bin/perl\fR, which is not
the winpid.  Use \f(CW\*(C`Cygwin::pid_to_winpid()\*(C'\fR and \f(CW\*(C`Cygwin::winpid_to_pid()\*(C'\fR
to translate between them.
.IP "\(bu" 4
Cygwin vs. Windows errors
.Sp
Under Cygwin, $^E is the same as $!.  When using Win32 \s-1API\s0 Functions,
use \f(CW\*(C`Win32::GetLastError()\*(C'\fR to get the last Windows error.
.IP "\(bu" 4
rebase errors on fork or system
.Sp
Using \f(CW\*(C`fork()\*(C'\fR or \f(CW\*(C`system()\*(C'\fR out to another perl after loading multiple dlls
may result on a \s-1DLL\s0 baseaddress conflict. The internal cygwin error
looks like like the following:
.Sp
.Vb 2
\& 0 [main] perl 8916 child_info_fork::abort: data segment start:
\& parent (0xC1A000) != child(0xA6A000)
.Ve
.Sp
or:
.Sp
.Vb 4
\& 183 [main] perl 3588 C:\ecygwin\ebin\eperl.exe: *** fatal error \-
\& unable to remap C:\ecygwin\ebin\ecygsvn_subr\-1\-0.dll to same address
\& as parent(0x6FB30000) != 0x6FE60000 46 [main] perl 3488 fork: child
\& 3588 \- died waiting for dll loading, errno11
.Ve
.Sp
See <http://cygwin.com/faq/faq\-nochunks.html#faq.using.fixing\-fork\-failures>
It helps if not too many DLLs are loaded in memory so the available address space is larger,
e.g. stopping the \s-1MS\s0 Internet Explorer might help.
.Sp
Use the perlrebase or rebase utilities to resolve the conflicting dll addresses.
The rebase package is included in the Cygwin setup. Use \fIsetup.exe\fR
from <http://www.cygwin.com/setup.exe> to install it.
.Sp
1. kill all perl processes and run \f(CW\*(C`perlrebase\*(C'\fR or
.Sp
2. kill all cygwin processes and services, start dash from cmd.exe and run \f(CW\*(C`rebaseall\*(C'\fR.
.IP "\(bu" 4
\&\f(CW\*(C`chown()\*(C'\fR
.Sp
On WinNT \f(CW\*(C`chown()\*(C'\fR can change a file's user and group IDs.  On Win9x \f(CW\*(C`chown()\*(C'\fR
is a no-op, although this is appropriate since there is no security model.
.IP "\(bu" 4
Miscellaneous
.Sp
File locking using the \f(CW\*(C`F_GETLK\*(C'\fR command to \f(CW\*(C`fcntl()\*(C'\fR is a stub that
returns \f(CW\*(C`ENOSYS\*(C'\fR.
.Sp
Win9x can not \f(CW\*(C`rename()\*(C'\fR an open file (although WinNT can).
.Sp
The Cygwin \f(CW\*(C`chroot()\*(C'\fR implementation has holes (it can not restrict file
access by native Win32 programs).
.Sp
Inplace editing \f(CW\*(C`perl \-i\*(C'\fR of files doesn't work without doing a backup
of the file being edited \f(CW\*(C`perl \-i.bak\*(C'\fR because of windowish restrictions,
therefore Perl adds the suffix \f(CW\*(C`.bak\*(C'\fR automatically if you use \f(CW\*(C`perl \-i\*(C'\fR
without specifying a backup extension.
.SS "Prebuilt methods:"
.IX Subsection "Prebuilt methods:"
.ie n .IP """Cwd::cwd""" 4
.el .IP "\f(CWCwd::cwd\fR" 4
.IX Item "Cwd::cwd"
Returns the current working directory.
.ie n .IP """Cygwin::pid_to_winpid""" 4
.el .IP "\f(CWCygwin::pid_to_winpid\fR" 4
.IX Item "Cygwin::pid_to_winpid"
Translates a cygwin pid to the corresponding Windows pid (which may or
may not be the same).
.ie n .IP """Cygwin::winpid_to_pid""" 4
.el .IP "\f(CWCygwin::winpid_to_pid\fR" 4
.IX Item "Cygwin::winpid_to_pid"
Translates a Windows pid to the corresponding cygwin pid (if any).
.ie n .IP """Cygwin::win_to_posix_path""" 4
.el .IP "\f(CWCygwin::win_to_posix_path\fR" 4
.IX Item "Cygwin::win_to_posix_path"
Translates a Windows path to the corresponding cygwin path respecting
the current mount points. With a second non-null argument returns an
absolute path. Double-byte characters will not be translated.
.ie n .IP """Cygwin::posix_to_win_path""" 4
.el .IP "\f(CWCygwin::posix_to_win_path\fR" 4
.IX Item "Cygwin::posix_to_win_path"
Translates a cygwin path to the corresponding cygwin path respecting
the current mount points. With a second non-null argument returns an
absolute path. Double-byte characters will not be translated.
.ie n .IP """Cygwin::mount_table()""" 4
.el .IP "\f(CWCygwin::mount_table()\fR" 4
.IX Item "Cygwin::mount_table()"
Returns an array of [mnt_dir, mnt_fsname, mnt_type, mnt_opts].
.Sp
.Vb 8
\&  perl \-e \*(Aqfor $i (Cygwin::mount_table) {print join(" ",@$i),"\en";}\*(Aq
\&  /bin c:\ecygwin\ebin system binmode,cygexec
\&  /usr/bin c:\ecygwin\ebin system binmode
\&  /usr/lib c:\ecygwin\elib system binmode
\&  / c:\ecygwin system binmode
\&  /cygdrive/c c: system binmode,noumount
\&  /cygdrive/d d: system binmode,noumount
\&  /cygdrive/e e: system binmode,noumount
.Ve
.ie n .IP """Cygwin::mount_flags""" 4
.el .IP "\f(CWCygwin::mount_flags\fR" 4
.IX Item "Cygwin::mount_flags"
Returns the mount type and flags for a specified mount point.
A comma-separated string of mntent\->mnt_type (always
\&\*(L"system\*(R" or \*(L"user\*(R"), then the mntent\->mnt_opts, where
the first is always \*(L"binmode\*(R" or \*(L"textmode\*(R".
.Sp
.Vb 2
\&  system|user,binmode|textmode,exec,cygexec,cygdrive,mixed,
\&  notexec,managed,nosuid,devfs,proc,noumount
.Ve
.Sp
If the argument is \*(L"/cygdrive\*(R", then just the volume mount settings,
and the cygdrive mount prefix are returned.
.Sp
User mounts override system mounts.
.Sp
.Vb 4
\&  $ perl \-e \*(Aqprint Cygwin::mount_flags "/usr/bin"\*(Aq
\&  system,binmode,cygexec
\&  $ perl \-e \*(Aqprint Cygwin::mount_flags "/cygdrive"\*(Aq
\&  binmode,cygdrive,/cygdrive
.Ve
.ie n .IP """Cygwin::is_binmount""" 4
.el .IP "\f(CWCygwin::is_binmount\fR" 4
.IX Item "Cygwin::is_binmount"
Returns true if the given cygwin path is binary mounted, false if the
path is mounted in textmode.
.ie n .IP """Cygwin::sync_winenv""" 4
.el .IP "\f(CWCygwin::sync_winenv\fR" 4
.IX Item "Cygwin::sync_winenv"
Cygwin does not initialize all original Win32 environment variables.
See the bottom of this page <http://cygwin.com/cygwin\-ug\-net/setup\-env.html>
for \*(L"Restricted Win32 environment\*(R".
.Sp
Certain Win32 programs called from cygwin programs might need some environment
variable, such as e.g. \s-1ADODB\s0 needs \f(CW%COMMONPROGRAMFILES\fR%.
Call \fICygwin::sync_winenv()\fR to copy all Win32 environment variables to your
process and note that cygwin will warn on every encounter of non-POSIX paths.
.SH "INSTALL PERL ON CYGWIN"
.IX Header "INSTALL PERL ON CYGWIN"
This will install Perl, including \fIman\fR pages.
.PP
.Vb 1
\&  make install 2>&1 | tee log.make\-install
.Ve
.PP
\&\s-1NOTE:\s0 If \f(CW\*(C`STDERR\*(C'\fR is redirected \f(CW\*(C`make install\*(C'\fR will \fBnot\fR prompt
you to install \fIperl\fR into \fI/usr/bin\fR.
.PP
You may need to be \fIAdministrator\fR to run \f(CW\*(C`make install\*(C'\fR.  If you
are not, you must have write access to the directories in question.
.PP
Information on installing the Perl documentation in \s-1HTML\s0 format can be
found in the \fI\s-1INSTALL\s0\fR document.
.SH "MANIFEST ON CYGWIN"
.IX Header "MANIFEST ON CYGWIN"
These are the files in the Perl release that contain references to Cygwin.
These very brief notes attempt to explain the reason for all conditional
code.  Hopefully, keeping this up to date will allow the Cygwin port to
be kept as clean as possible.
.IP "Documentation" 4
.IX Item "Documentation"
.Vb 10
\& INSTALL README.cygwin README.win32 MANIFEST
\& pod/perl.pod pod/perlport.pod pod/perlfaq3.pod
\& pod/perldelta.pod pod/perl5004delta.pod pod/perl56delta.pod
\& pod/perl561delta.pod pod/perl570delta.pod pod/perl572delta.pod
\& pod/perl573delta.pod pod/perl58delta.pod pod/perl581delta.pod
\& pod/perl590delta.pod pod/perlhist.pod pod/perlmodlib.pod
\& pod/perltoc.pod Porting/Glossary pod/perlgit.pod
\& Porting/checkAUTHORS.pl
\& dist/Cwd/Changes ext/Compress\-Raw\-Zlib/Changes
\& dist/Time\-HiRes/Changes
\& ext/Compress\-Raw\-Zlib/README ext/Compress\-Zlib/Changes
\& ext/DB_File/Changes ext/Encode/Changes ext/Sys\-Syslog/Changes
\& ext/Win32API\-File/Changes
\& lib/ExtUtils/CBuilder/Changes lib/ExtUtils/Changes
\& lib/ExtUtils/NOTES lib/ExtUtils/PATCHING lib/ExtUtils/README
\& lib/Net/Ping/Changes lib/Test/Harness/Changes
\& lib/Term/ANSIColor/ChangeLog lib/Term/ANSIColor/README
\& README.symbian symbian/TODO
.Ve
.IP "Build, Configure, Make, Install" 4
.IX Item "Build, Configure, Make, Install"
.Vb 10
\& cygwin/Makefile.SHs
\& ext/IPC/SysV/hints/cygwin.pl
\& ext/NDBM_File/hints/cygwin.pl
\& ext/ODBM_File/hints/cygwin.pl
\& hints/cygwin.sh
\& Configure             \- help finding hints from uname,
\&                         shared libperl required for dynamic loading
\& Makefile.SH Cross/Makefile\-cross\-SH
\&                       \- linklibperl
\& Porting/patchls       \- cygwin in port list
\& installman            \- man pages with :: translated to .
\& installperl           \- install dll, install to \*(Aqpods\*(Aq
\& makedepend.SH         \- uwinfix
\& regen_lib.pl          \- file permissions
\&
\& NetWare/Makefile
\& plan9/mkfile
\& symbian/sanity.pl symbian/sisify.pl
\& hints/uwin.sh
\& vms/descrip_mms.template
\& win32/Makefile win32/makefile.mk
.Ve
.IP "Tests" 4
.IX Item "Tests"
.Vb 10
\& t/io/fs.t             \- no file mode checks if not ntsec
\&                         skip rename() check when not
\&                         check_case:relaxed
\& t/io/tell.t           \- binmode
\& t/lib/cygwin.t        \- builtin cygwin function tests
\& t/op/groups.t         \- basegroup has ID = 0
\& t/op/magic.t          \- $^X/symlink WORKAROUND, s/.exe//
\& t/op/stat.t           \- no /dev, skip Win32 ftCreationTime quirk
\&                         (cache manager sometimes preserves ctime of
\&                         file previously created and deleted), no \-u
\&                         (setuid)
\& t/op/taint.t          \- can\*(Aqt use empty path under Cygwin Perl
\& t/op/time.t           \- no tzset()
.Ve
.IP "Compiled Perl Source" 4
.IX Item "Compiled Perl Source"
.Vb 10
\& EXTERN.h              \- _\|_declspec(dllimport)
\& XSUB.h                \- _\|_declspec(dllexport)
\& cygwin/cygwin.c       \- os_extras (getcwd, spawn, and several
\&                         Cygwin:: functions)
\& perl.c                \- os_extras, \-i.bak
\& perl.h                \- binmode
\& doio.c                \- win9x can not rename a file when it is open
\& pp_sys.c              \- do not define h_errno, init
\&                         _pwent_struct.pw_comment
\& util.c                \- use setenv
\& util.h                \- PERL_FILE_IS_ABSOLUTE macro
\& pp.c                  \- Comment about Posix vs IEEE math under
\&                         Cygwin
\& perlio.c              \- CR/LF mode
\& perliol.c             \- Comment about EXTCONST under Cygwin
.Ve
.IP "Compiled Module Source" 4
.IX Item "Compiled Module Source"
.Vb 10
\& ext/Compress\-Raw\-Zlib/Makefile.PL
\&                       \- Can\*(Aqt install via CPAN shell under Cygwin
\& ext/Compress\-Raw\-Zlib/zlib\-src/zutil.h
\&                       \- Cygwin is Unix\-like and has vsnprintf
\& ext/Errno/Errno_pm.PL \- Special handling for Win32 Perl under
\&                         Cygwin
\& ext/POSIX/POSIX.xs    \- tzname defined externally
\& ext/SDBM_File/sdbm/pair.c
\&                       \- EXTCONST needs to be redefined from
\&                         EXTERN.h
\& ext/SDBM_File/sdbm/sdbm.c
\&                       \- binary open
\& ext/Sys/Syslog/Syslog.xs
\&                       \- Cygwin has syslog.h
\& ext/Sys/Syslog/win32/compile.pl
\&                       \- Convert paths to Windows paths
\& ext/Time\-HiRes/HiRes.xs
\&                       \- Various timers not available
\& ext/Time\-HiRes/Makefile.PL
\&                       \- Find w32api/windows.h
\& ext/Win32/Makefile.PL \- Use various libraries under Cygwin
\& ext/Win32/Win32.xs    \- Child dir and child env under Cygwin
\& ext/Win32API\-File/File.xs
\&                       \- _open_osfhandle not implemented under
\&                         Cygwin
\& ext/Win32CORE/Win32CORE.c
\&                       \- _\|_declspec(dllexport)
.Ve
.IP "Perl Modules/Scripts" 4
.IX Item "Perl Modules/Scripts"
.Vb 10
\& ext/B/t/OptreeCheck.pm \- Comment about stderr/stdout order under
\&                          Cygwin
\& ext/Digest\-SHA/bin/shasum
\&                       \- Use binary mode under Cygwin
\& ext/Sys/Syslog/win32/Win32.pm
\&                       \- Convert paths to Windows paths
\& ext/Time\-HiRes/HiRes.pm
\&                       \- Comment about various timers not available
\& ext/Win32API\-File/File.pm
\&                       \- _open_osfhandle not implemented under
\&                         Cygwin
\& ext/Win32CORE/Win32CORE.pm
\&                       \- History of Win32CORE under Cygwin
\& lib/Cwd.pm            \- hook to internal Cwd::cwd
\& lib/ExtUtils/CBuilder/Platform/cygwin.pm
\&                       \- use gcc for ld, and link to libperl.dll.a
\& lib/ExtUtils/CBuilder.pm
\&                       \- Cygwin is Unix\-like
\& lib/ExtUtils/Install.pm \- Install and rename issues under Cygwin
\& lib/ExtUtils/MM.pm    \- OS classifications
\& lib/ExtUtils/MM_Any.pm \- Example for Cygwin
\& lib/ExtUtils/MakeMaker.pm
\&                       \- require MM_Cygwin.pm
\& lib/ExtUtils/MM_Cygwin.pm
\&                       \- canonpath, cflags, manifypods, perl_archive
\& lib/File/Fetch.pm     \- Comment about quotes using a Cygwin example
\& lib/File/Find.pm      \- on remote drives stat() always sets
\&                         st_nlink to 1
\& lib/File/Spec/Cygwin.pm \- case_tolerant
\& lib/File/Spec/Unix.pm \- preserve //unc
\& lib/File/Spec/Win32.pm \- References a message on cygwin.com
\& lib/File/Spec.pm      \- Pulls in lib/File/Spec/Cygwin.pm
\& lib/File/Temp.pm      \- no directory sticky bit
\& lib/Module/CoreList.pm \- List of all module files and versions
\& lib/Net/Domain.pm     \- No domainname command under Cygwin
\& lib/Net/Netrc.pm      \- Bypass using stat() under Cygwin
\& lib/Net/Ping.pm       \- ECONREFUSED is EAGAIN under Cygwin
\& lib/Pod/Find.pm       \- Set \*(Aqpods\*(Aq dir
\& lib/Pod/Perldoc/ToMan.pm \- \*(Aq\-c\*(Aq switch for pod2man
\& lib/Pod/Perldoc.pm    \- Use \*(Aqless\*(Aq pager, and use .exe extension
\& lib/Term/ANSIColor.pm \- Cygwin terminal info
\& lib/perl5db.pl        \- use stdin not /dev/tty
\& utils/perlbug.PL      \- Add CYGWIN environment variable to report
.Ve
.IP "Perl Module Tests" 4
.IX Item "Perl Module Tests"
.Vb 10
\& dist/Cwd/t/cwd.t
\& ext/Compress\-Zlib/t/14gzopen.t
\& ext/DB_File/t/db\-btree.t
\& ext/DB_File/t/db\-hash.t
\& ext/DB_File/t/db\-recno.t
\& ext/DynaLoader/t/DynaLoader.t
\& ext/File\-Glob/t/basic.t
\& ext/GDBM_File/t/gdbm.t
\& ext/POSIX/t/sysconf.t
\& ext/POSIX/t/time.t
\& ext/SDBM_File/t/sdbm.t
\& ext/Sys/Syslog/t/syslog.t
\& ext/Time\-HiRes/t/HiRes.t
\& ext/Win32/t/Unicode.t
\& ext/Win32API\-File/t/file.t
\& ext/Win32CORE/t/win32core.t
\& lib/AnyDBM_File.t
\& lib/Archive/Extract/t/01_Archive\-Extract.t
\& lib/Archive/Tar/t/02_methods.t
\& lib/ExtUtils/t/Embed.t
\& lib/ExtUtils/t/eu_command.t
\& lib/ExtUtils/t/MM_Cygwin.t
\& lib/ExtUtils/t/MM_Unix.t
\& lib/File/Compare.t
\& lib/File/Copy.t
\& lib/File/Find/t/find.t
\& lib/File/Path.t
\& lib/File/Spec/t/crossplatform.t
\& lib/File/Spec/t/Spec.t
\& lib/Net/hostent.t
\& lib/Net/Ping/t/110_icmp_inst.t
\& lib/Net/Ping/t/500_ping_icmp.t
\& lib/Net/t/netrc.t
\& lib/Pod/Simple/t/perlcyg.pod
\& lib/Pod/Simple/t/perlcygo.txt
\& lib/Pod/Simple/t/perlfaq.pod
\& lib/Pod/Simple/t/perlfaqo.txt
\& lib/User/grent.t
\& lib/User/pwent.t
.Ve
.SH "BUGS ON CYGWIN"
.IX Header "BUGS ON CYGWIN"
Support for swapping real and effective user and group IDs is incomplete.
On WinNT Cygwin provides \f(CW\*(C`setuid()\*(C'\fR, \f(CW\*(C`seteuid()\*(C'\fR, \f(CW\*(C`setgid()\*(C'\fR and \f(CW\*(C`setegid()\*(C'\fR.
However, additional Cygwin calls for manipulating WinNT access tokens
and security contexts are required.
.SH "AUTHORS"
.IX Header "AUTHORS"
Charles Wilson <cwilson@ece.gatech.edu>,
Eric Fifer <egf7@columbia.edu>,
alexander smishlajev <als@turnhere.com>,
Steven Morlock <newspost@morlock.net>,
Sebastien Barre <Sebastien.Barre@utc.fr>,
Teun Burgers <burgers@ecn.nl>,
Gerrit P. Haase <gp@familiehaase.de>,
Reini Urban <rurban@cpan.org>,
Jan Dubois <jand@activestate.com>,
Jerry D. Hedden <jdhedden@cpan.org>.
.SH "HISTORY"
.IX Header "HISTORY"
Last updated: 2012\-02\-08
