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/
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.
· `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'.
· /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
· /usr/bin
If you do not have a /usr/bin directory, Configure
will not prompt you to install perl into /usr/bin.
· nroff
If you do not have nroff (which is part of the groff
package), Configure will not prompt you to install man
pages.
· 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
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/'.
· `-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.
http://dome.weeg.uiowa.edu/pub/domestic/sos/libcrypt.tgz
More information can also be found at:
http://miracle.geol.msu.ru/sos/
· `-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).
· `-ldb' (`use DB_File')
BerkeleyDB is available for Cygwin. Some details can
be found in ext/DB_File/DB_File.pm.
· `-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.
· `-Uusedl'
Undefining this symbol forces Perl to be compiled
statically.
· `-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.
· `-Dusemultiplicity'
Multiplicity is required when embedding Perl in a C
program and using more than one interpreter instance.
This works with the Cygwin port.
· `-Duseperlio'
The PerlIO abstraction works with the Cygwin port.
· `-Duse64bitint'
gcc supports 64-bit integers. However, several addi
tional long long functions are necessary to use them
available with Cygwin.
· `-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.
· `-Dusethreads'
POSIX threads are not yet implemented in Cygwin.
· `-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.
· 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.
· 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.
· 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:
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.
· Checking how std your stdio is...
Configure reports:
Your stdio doesn't appear very std.
This is correct.
· 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 $installbin is in your
current `PATH'. If this is not the case or if you do not
have an install program, ``make'' will fail at some point.
directory to someplace in your `PATH'.
TEST
There are two steps to running the test suite:
make test 2>&1 | tee log.make-test
cd t;./perl harness 2>&1 | tee ../log.harness
The same tests are run both times, but more information is
provided when running as ``./perl harness''.
Test results vary depending on your host system and your
Cygwin configuration. It is possible that Cygwin will
pass all the tests, but it is more likely that some tests
will fail for one of these reasons.
File Permissions
UNIX file permissions are based on sets of mode bits for
{read,write,execute} for each {user,group,other}. By
default Cygwin only tracks the Win32 readonly attribute
represented as the UNIX file user write bit (files are
always readable, files are executable if they have a
.{com,bat,exe} extension or begin with `#!', directories
are always readable and executable). On WinNT with the
ntea `CYGWIN' setting, the remaining mode bits are stored
as extended attributes. On WinNT with the ntsec `CYGWIN'
setting, permissions use the standard WinNT security
descriptors and access control lists. Without one of
these options, these tests will fail:
Failed Test List of failed
------------------------------------
io/fs.t 5, 7, 9-10
lib/anydbm.t 2
lib/db-btree.t 20
lib/db-hash.t 16
lib/db-recno.t 18
lib/gdbm.t 2
lib/ndbm.t 2
lib/odbm.t 2
lib/sdbm.t 2
op/stat.t 9, 20 (.tmp not an executable extension)
Hard Links
FAT partitions do not support hard links (whereas NTFS
does), in which case Cygwin implements link() by copying
the file. These tests will fail:
------------------------------------
io/fs.t 4
op/stat.t 3
Filetime Granularity
On FAT partitions the filetime granularity is 2 seconds.
The following test will fail:
Failed Test List of failed
------------------------------------
io/fs.t 18
Tainting Checks
When Perl is running in taint mode, `$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:
------------------------------------
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.
· 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/
· 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:
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.
· .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/
· 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.
· 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
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
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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