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NAME
       README.cygwin - Perl for Cygwin

SYNOPSIS
       This document will help you configure, make, test and
       install Perl on Cygwin.  This document also describes fea-
       tures of Cygwin that will affect how Perl behaves at run-
       time.

       NOTE: There are pre-built Perl packages available for Cyg-
       win and a version of Perl is provided on the Cygwin CD.
       If you have no need to customize the configuration, con-
       sider using one of these packages:

         http://cygutils.netpedia.net/


PREREQUISITES
       Cygwin = GNU+Cygnus+Windows (Don't leave UNIX without it)

       The Cygwin tools are ports of the popular GNU development
       tools for Win32 platforms.  They run thanks to the Cygwin
       library which provides the UNIX system calls and environ-
       ment these programs expect.  More information about this
       project can be found at:

         http://sourceware.cygnus.com/cygwin/

       A recent net or commercial release of Cygwin is required.

       At the time this document was written, the port required
       recent development snapshots that were expected to stabi-
       lize early in 2000 and be released to the net as B21 and
       commercially as v1.1.

       NOTE: At this point, minimal effort has been made to pro-
       vide compatibility with old (beta) Cygwin releases.  The
       focus has been to provide a high quality release and not
       worry about working around old Cygwin bugs.  If you wish
       to use Perl with Cygwin B20.1 or earlier, consider using
       either perl5.005_03 or perl5.005_62, which are available
       in source and binary form at `http://cygutils.netpe-
       dia.net/' or on the Cygwin CD.  If there is significant
       demand, a patch kit can be developed to port back to ear-
       lier Cygwin versions.

       Compiler

       A recent net or commercial release of gcc is required.

       At the time this document was written, gcc-2.95.2 was cur-
       rent and could be downloaded from:

         ftp://ftp.xraylith.wisc.edu/pub/khan/gnu-win32/cygwin/gcc-2.95.2/



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       Cygwin Configuration

       While building Perl some changes may be necessary to your
       Cygwin setup so that Perl builds cleanly.  These changes
       are not required for normal Perl usage.

       NOTE: The binaries that are built will run on all Win32
       versions.  They do not depend on your host system (Win9x,
       WinNT) or your Cygwin configuration (ntea, ntsec,
       binary/text mounts).  The only dependencies come from
       hardcoded pathnames like `/usr/local'.  However, your host
       system and Cygwin configuration will affect Perl's runtime
       behavior (see the TEST entry elsewhere in this document).
       Some regression tests may fail in different ways depending
       on your setup.  For now, the test suite does not skip
       tests that do not make sense given a particular setup.  If
       a test can pass in some Cygwin setup, it is left in and
       explainable test failures are documented.

       o `PATH'
           Set the `PATH' environment variable so that Configure
           finds the Cygwin versions of programs.  Any Windows
           directories should be removed or moved to the end of
           your `PATH'.

       o /bin/cat.exe
           There should be an instance of cat in /bin (or
           /usr/bin).  Configure tests `#!/bin/cat' and if it is
           not found, you will see the error:

             Configure: ./try: No such file or directory


       o /usr/bin
           If you do not have a /usr/bin directory, Configure
           will not prompt you to install perl into /usr/bin.

       o nroff
           If you do not have nroff (which is part of the groff
           package), Configure will not prompt you to install man
           pages.

       o Permissions
           On WinNT with either the ntea or ntsec `CYGWIN' set-
           tings, directory and file permissions may not be set
           correctly.  Since the build process creates files and
           directories, to be safe you may want to run a ``chmod
           -R +w *'' on the entire Perl source tree.

           Also, it is a well known WinNT "feature" that files
           created by a login that is a member of the Administra-
           tors group will be owned by the Administrators group.
           Depending on your umask, you may find that you can not
           write to files that you just created (because you are



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           no longer the owner).  When using the ntsec `CYGWIN'
           setting, this is not an issue because it "corrects"
           the ownership to what you would expect on a UNIX sys-
           tem.

CONFIGURE
       The default options gathered by Configure with the assis-
       tance of hints/cygwin.sh will build a Perl that supports
       dynamic loading (which requires a shared libperl.dll).

       This will run Configure and keep a record:

         ./Configure 2>&1 | tee log.configure

       If you are willing to accept all the defaults add a -d
       option.  However, several useful customizations are avail-
       able.

       Strip Binaries

       It is possible to strip the EXEs and DLLs created by the
       build process.  The resulting binaries will be signifi-
       cantly smaller.  If you want the binaries to be stripped,
       you can either add a -s option when Configure prompts you,

         Any additional ld flags (NOT including libraries)? [none] -s
         Any special flags to pass to gcc to use dynamic linking? [none] -s
         Any special flags to pass to ld2 to create a dynamically loaded library?
         [none] -s

       or you can edit hints/cygwin.sh and uncomment the relevant
       variables near the end of the file.

       Optional Libraries

       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 at `http://cygutils.netpe-
       dia.net/'.

       o `-lcrypt'
           The crypt libraries in GNU libc have been ported to
           Cygwin.

           The DES based Ultra Fast Crypt port was done by Alexey
           Truhan:

             http://dome.weeg.uiowa.edu/pub/domestic/sos/cw32crypt-dist-0.tgz

           NOTE: There are various export restrictions on DES
           implementations, see the glibc README for more
           details.



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           The MD5 port was done by Andy Piper:

             http://dome.weeg.uiowa.edu/pub/domestic/sos/libcrypt.tgz

           More information can also be found at:

             http://miracle.geol.msu.ru/sos/


       o `-lgdbm' (`use GDBM_File')
           GDBM is available for Cygwin.  GDBM's ndbm/dbm compat-
           ibility feature also makes `NDBM_File' and `ODBM_File'
           possible (although they add little extra value).

       o `-ldb' (`use DB_File')
           BerkeleyDB is available for Cygwin.  Some details can
           be found in ext/DB_File/DB_File.pm.

       o `-lcygipc' (`use IPC::SysV')
           A port of SysV IPC is available for Cygwin.

           NOTE: This has not been extensively tested.  In par-
           ticular, `d_semctl_semun' is undefined because it
           fails a configure test and on Win9x the shm*() func-
           tions seem to hang.

       Configure-time Options

       The INSTALL 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.

       o `-Uusedl'
           Undefining this symbol forces Perl to be compiled
           statically.

       o `-Uusemymalloc'
           By default Perl uses the malloc() included with the
           Perl source.  If you want to force Perl to build with
           the system malloc() undefine this symbol.

       o `-Dusemultiplicity'
           Multiplicity is required when embedding Perl in a C
           program and using more than one interpreter instance.
           This works with the Cygwin port.

       o `-Duseperlio'
           The PerlIO abstraction works with the Cygwin port.

       o `-Duse64bitint'
           gcc supports 64-bit integers.  However, several addi-
           tional long long functions are necessary to use them



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           within Perl ({strtol,strtoul}l).  These are not yet
           available with Cygwin.

       o `-Duselongdouble'
           gcc supports long doubles (12 bytes).  However, sev-
           eral additional long double math functions are neces-
           sary to use them within Perl
           ({atan2,cos,exp,floor,fmod,frexp,log,modf,pow,sin,sqrt}l,str-
           told).  These are not yet available with Cygwin.

       o `-Dusethreads'
           POSIX threads are not yet implemented in Cygwin.

       o `-Duselargefiles'
           Although Win32 supports large files, Cygwin currently
           uses 32-bit integers for internal size and position
           calculations.

       Suspicious Warnings

       You may see some messages during Configure that seem sus-
       picious.

       o Whoa There
           Cygwin does not yet implement chroot(), setegid() or
           seteuid() functionality, but has stub functions that
           return `ENOSYS'.  You will see a message when Config-
           ure detects that its guess conflicts with the hint
           file.

             *** WHOA THERE!!! ***
                 The recommended value for $d_chroot on this machine was "undef"!
                 Keep the recommended value? [y]

           You should keep the recommended value.

       o dlsym
           ld2 is needed to build dynamic libraries, but it does
           not exist when dlsym() checking occurs (it is not cre-
           ated until ``make'' runs).  You will see the following
           message:

             Checking whether your dlsym() needs a leading underscore ...
             I can't compile and run the test program.
             I'm guessing that dlsym doesn't need a leading underscore.

           Since the guess is correct, this is not a problem.

       o Win9x and d_eofnblk
           Win9x does not correctly report `EOF' with a non-
           blocking read on a closed pipe.  You will see the fol-
           lowing messages:





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             But it also returns -1 to signal EOF, so be careful!
             WARNING: you can't distinguish between EOF and no data!

             *** WHOA THERE!!! ***
                 The recommended value for $d_eofnblk on this machine was "define"!
                 Keep the recommended value? [y]

           At least for consistency with WinNT, you should keep
           the recommended value.

       o Checking how std your stdio is...
           Configure reports:

             Your stdio doesn't appear very std.

           This is correct.

       o Compiler/Preprocessor defines
           The following error occurs because of the Cygwin
           `#define' of `_LONG_DOUBLE':

             Guessing which symbols your C compiler and preprocessor define...
             try.c:3847: parse error

           This failure does not seem to cause any problems.

MAKE
       Simply run make and wait:

         make 2>&1 | tee log.make


       Warnings

       Warnings like these are normal:

         warning: overriding commands for target <file>
         warning: ignoring old commands for target <file>

         Warning: no export definition file provided
         dllwrap will create one, but may not be what you want


       ld2

       During ``make'', ld2 will be created and installed in your
       $installbin directory (where you said to put public exe-
       cutables).  It does not wait until the ``make install''
       process to install the ld2 script, this is because the
       remainder of the ``make'' refers to ld2 without fully
       specifying its path and does this from multiple subdirec-
       tories.  The assumption is that $installbin is in your
       current `PATH'.  If this is not the case or if you do not
       have an install program, ``make'' will fail at some point.



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       If this happens, just manually copy ld2 from the source
       directory to someplace in your `PATH'.

TEST
       There are two steps to running the test suite:

         make test 2>&1 | tee log.make-test

         cd t;./perl harness 2>&1 | tee ../log.harness

       The same tests are run both times, but more information is
       provided when running as ``./perl harness''.

       Test results vary depending on your host system and your
       Cygwin configuration.  It is possible that Cygwin will
       pass all the tests, but it is more likely that some tests
       will fail for one of these reasons.

       File Permissions

       UNIX 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 readonly attribute
       represented as the UNIX file user write bit (files are
       always readable, files are executable if they have a
       .{com,bat,exe} extension or begin with `#!', directories
       are always readable and executable).  On WinNT with the
       ntea `CYGWIN' setting, the remaining mode bits are stored
       as extended attributes.  On WinNT with the ntsec `CYGWIN'
       setting, permissions use the standard WinNT security
       descriptors and access control lists.  Without one of
       these options, these tests will fail:

         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)


       Hard Links

       FAT partitions do not support hard links (whereas NTFS
       does), in which case Cygwin implements link() by copying
       the file.  These tests will fail:





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         Failed Test           List of failed
         ------------------------------------
         io/fs.t               4
         op/stat.t             3


       Filetime Granularity

       On FAT partitions the filetime granularity is 2 seconds.
       The following test will fail:

         Failed Test           List of failed
         ------------------------------------
         io/fs.t               18


       Tainting Checks

       When Perl is running in taint mode, `$ENV{PATH}' is con-
       sidered tainted and not used, so DLLs not in the default
       system directories will not be found.  While the tests are
       running you will see warnings popup from the system with
       messages like:

         Win9x
           Error Starting Program
           A required .DLL file, CYGWIN1.DLL, was not found

         WinNT
           perl.exe or sh.exe - Unable to Locate DLL
           The dynamic link library cygwin1.dll could not be found in the
             specified path ...

       Just click OK and ignore them.  When running ``make
       test'', 2 popups occur.  During ``./perl harness'', 4 pop-
       ups occur.  Also, these tests will fail:

         Failed Test           List of failed
         ------------------------------------
         op/taint.t            1, 3, 31, 37

       Alternatively, you can copy cygwin1.dll into one of the
       Windows system directories (although, this is not recom-
       mended).

       /etc/group

       Cygwin does not require /etc/group, in which case the
       op/grent.t test will be skipped.  The check performed by
       op/grent.t expects to see entries that use the members
       field, otherwise this test will fail:






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         Failed Test           List of failed
         ------------------------------------
         op/grent.t            1


       Unexplained Failures

       Any additional tests that fail are likely due to bugs in
       Cygwin or the optional libraries.  It is expected that by
       the time of the next net release most of these will be
       solved so they are not described here.

       Script Portability

       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 only a very brief guide to
       portability, more information can be found in the Cygwin
       documentation.

       o Pathnames
           Cygwin pathnames can be separated by forward (/) or
           backward (\) slashes.  They may also begin with drive
           letters (C:) or Universal Naming Codes (//UNC).  DOS
           device names (aux, con, prn, com*, lpt?) are invalid
           as base filenames.  However, they can be used in
           extensions (e.g., hello.aux).  Names may not contain
           these characters:

             : * ? " < > |

           File names are case insensitive, but case preserving.
           With the mixed `CYGWIN' setting, file names are mixed-
           case (although, directory names remain case insensi-
           tive).

           The mixed setting is only available with the
           "coolview" version of cygwin1.dll provided by Sergey
           Okhapkin at:

             ftp://ftp.franken.de/pub/win32/develop/gnuwin32/cygwin/porters/Okhapkin_Sergey/


       o Text/Binary
           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
           open() is determined by the mode of the mount that
           underlies the file.  Perl provides a binmode() func-
           tion to set binary mode on files that otherwise would
           be treated as text.  sysopen() with the `O_TEXT' flag
           sets text mode on files that otherwise would be
           treated as binary:



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               sysopen(FOO, "bar", O_WRONLY|O_CREAT|O_TEXT)

           lseek(), tell() and sysseek() only work with files
           opened in binary mode.

           The text/binary issue is covered at length in the Cyg-
           win documentation.

       o .exe
           The Cygwin stat() makes the .exe extension transparent
           by looking for a foo.exe when you ask for foo (unless
           a foo also exists).  Cygwin does not require a .exe
           extension, but gcc adds it automatically when building
           a program.  However, when accessing an executable as a
           normal file (e.g., install or cp in a makefile) the
           .exe is not transparent.

           NOTE: There is a version of install that understands
           the .exe semantics, it can be found at:

             ftp://ftp.franken.de/pub/win32/develop/gnuwin32/cygwin/porters/Humblet_Pierre_A/


       o chown()
           On WinNT with the ntsec `CYGWIN' setting, chown() can
           change a file's user and group IDs.  In all other con-
           figurations chown() is a no-op, although this is
           appropriate on Win9x since there is no security model.

       o Miscellaneous
           File locking using the `F_GETLK' command to fcntl() is
           a stub that returns `ENOSYS'.

           Win9x can not rename() an open file (although WinNT
           can).

INSTALL
       This will install Perl, including man pages.

         make install | tee log.make-install

       NOTE: If `STDERR' is redirected ``make install'' will not
       prompt you to install perl into /usr/bin.

       You may need to be Administrator to run ``make install''.
       If you are not, you must have write access to the directo-
       ries in question.

       Information on installing the Perl documentation in HTML
       format can be found in the INSTALL document.

MANIFEST
       These are the files in the Perl release that contain ref-
       erences to Cygwin.  These very brief notes attempt to



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       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.

       Documentation
             INSTALL README.cygwin
             Changes Changes5.005 Changes5.004
             AUTHORS MAINTAIN MANIFEST README.win32
             pod/perl.pod pod/perlfaq3.pod pod/perlhist.pod pod/perlmodlib.pod
             pod/perlport.pod pod/perltoc.pod pod/perl5004delta.pod


       Build, Configure, Make, Install
             cygwin/Makefile.SHs
             cygwin/ld2.in
             cygwin/perlld.in
             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           - linklibperl
             Porting/patchls       - cygwin in port list
             installman            - man pages with :: translated to .
             installperl           - install dll/ld2/perlld, install to pods
             makedepend.SH         - uwinfix


       Tests
             t/io/tell.t           - binmode
             t/lib/glob-basic.t    - Win32 directory list access differs from read mode
             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)


       Compiled Perl Source
             EXTERN.h              - __declspec(dllimport)
             XSUB.h                - __declspec(dllexport)
             cygwin/cygwin.c       - os_extras (getcwd)
             perl.c                - os_extras
             perl.h                - binmode
             doio.c                - win9x can not rename a file when it is open
             pp_sys.c              - do not define h_errno
             mg.c                  - environ WORKAROUND
             unixish.h             - environ WORKAROUND
             util.c                - environ WORKAROUND


       Compiled Module Source





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             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


       Perl Modules/Scripts
             lib/Cwd.pm            - hook to internal Cwd::cwd
             lib/ExtUtils/MakeMaker.pm
                                   - require MM_Cygwin.pm
             lib/ExtUtils/MM_Cygwin.pm
                                   - canonpath, cflags, manifypods, perl_archive
             lib/File/Spec/Unix.pm - preserve //unc
             lib/perl5db.pl        - use stdin not /dev/tty
             utils/perlcc.PL       - DynaLoader.a in compile, -DUSEIMPORTLIB
             utils/perldoc.PL      - version comment


BUGS
       Upon each start, make warns that a rule for perlmain.o is
       overridden (but there seems to be no better solution than
       adding an explicit define).

       ``make clean'' does not remove library .def and
       .exe.stackdump files.

       The ld2 script contains references to the source direc-
       tory.  You should change these to `/usr/local/bin' (or
       whatever) after install.

AUTHORS
       Charles Wilson <cwilson@ece.gatech.edu>, Eric Fifer
       <efifer@sanwaint.com>, alexander smishlajev <als@turn-
       here.com>, Steven Morlock <newspost@morlock.net>,
       Sebastien Barre <Sebastien.Barre@utc.fr>, Teun Burgers
       <burgers@ecn.nl>.

HISTORY
       Last updated: 1 March 2000

















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