Index of Section 1 Manual Pages
| Interix / SUA | perlcygwin.1 | Interix / SUA |
PERLCYGWIN(1) Perl Programmers Reference Guide PERLCYGWIN(1)
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 in the normal Cygwin
install. If you do not need to customize the configura-
tion, consider using one of those packages.
PREREQUISITES FOR COMPILING PERL ON CYGWIN
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://www.cygwin.com/
A recent net or commercial release of Cygwin is required.
At the time this document was last updated, Cygwin 1.5.2
was current.
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/WinME, WinNT/Win2K) or your Cygwin configuration
(ntea, ntsec, binary/text mounts). The only dependencies
come from hard-coded pathnames like "/usr/local". How-
ever, your host system and Cygwin configuration will
affect Perl's runtime behavior (see "TEST").
* "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".
* 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 directo-
ries and files, 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
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 PERL ON CYGWIN
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 run Config-
ure with -de. However, several useful customizations are
available.
Stripping Perl Binaries on Cygwin
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 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.
* "-lcrypt"
The crypt package distributed with Cygwin is a Linux
compatible 56-bit DES crypt port by Corinna Vinschen.
Alternatively, the crypt libraries in GNU libc have
been ported to Cygwin.
The DES based Ultra Fast Crypt port was done by Alexey
Truhan:
ftp://ftp.uni-erlangen.de/pub/pc/gnuwin32/cygwin/porters/Okhapkin_Sergey/cw32crypt-dist-0.tgz
NOTE: There are various export restrictions on DES
implementations, see the glibc README for more
details.
The MD5 port was done by Andy Piper:
ftp://ftp.uni-erlangen.de/pub/pc/gnuwin32/cygwin/porters/Okhapkin_Sergey/libcrypt.tgz
* "-lgdbm" ("use GDBM_File")
GDBM is available for Cygwin.
NOTE: The GDBM library only works on NTFS partitions.
* "-ldb" ("use DB_File")
BerkeleyDB is available for Cygwin.
NOTE: The BerkeleyDB library only completely works on
NTFS partitions.
* "-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. It also creates a compile time
dependency because perl.h includes and
(which will be required in the future when
compiling CPAN modules). CURRENTLY NOT SUPPORTED!
* "-lutil"
Included with the standard Cygwin netrelease is the
inetutils package which includes libutil.a.
Configure-time Options for Perl on Cygwin
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.
* "-Uuseperlio"
Undefining this symbol disables the PerlIO abstrac-
tion. PerlIO is now the default; it is not recom-
mended to disable PerlIO.
* "-Dusemultiplicity"
Multiplicity is required when embedding Perl in a C
program and using more than one interpreter instance.
This works with the Cygwin port.
* "-Duse64bitint"
By default Perl uses 32 bit integers. If you want to
use larger 64 bit integers, define this symbol.
* "-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, isnan, log, modf, pow, sin, sqrt}l, str-
told). These are not yet available with Cygwin.
* "-Dusethreads"
POSIX threads are implemented in Cygwin, define this
symbol if you want a threaded perl.
* "-Duselargefiles"
Cygwin uses 64-bit integers for internal size and
position calculations, this will be correctly detected
and defined by Configure.
* "-Dmksymlinks"
Use this to build perl outside of the source tree.
This works with Cygwin. Details can be found in the
INSTALL document. This is the recommended way to
build perl from sources.
Suspicious Warnings on Cygwin
You may see some messages during Configure that seem sus-
picious.
* dlsym()
ld2 is needed to build dynamic libraries, but it does
not exist when "dlsym()" checking occurs (it is not
created until "make" runs). You will see the follow-
ing message:
Checking whether your C needs a leading underscore ...
ld2: not found
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:
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.
* 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:: missing binary operator
This failure does not seem to cause any problems.
With older gcc versions, "parse error" is reported
instead of "missing binary operator".
MAKE ON CYGWIN
Simply run make and wait:
make 2>&1 | tee log.make
Errors on Cygwin
Errors like these are normal:
...
make: [extra.pods] Error 1 (ignored)
...
make: [extras.make] Error 1 (ignored)
ld2 on Cygwin
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" pro-
cess to install the ld2 script, this is because the
remainder of the "make" refers to ld2 without fully speci-
fying its path and does this from multiple subdirectories.
The assumption is that $installbin is in your current
"PATH". If this is not the case "make" will fail at some
point. If this happens, just manually copy ld2 from the
source directory to somewhere in your "PATH".
TEST ON CYGWIN
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. If a test can pass in some Cygwin
setup, it is always attempted and explainable test fail-
ures 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.
File Permissions on Cygwin
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 read-only 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 additional mode bits are stored
as extended file attributes. On WinNT with the ntsec
"CYGWIN" setting, permissions use the standard WinNT secu-
rity descriptors and access control lists. Without one of
these options, these tests will fail (listing not updated
yet):
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)
NDBM_File and ODBM_File do not work on FAT filesystems
Do not use NDBM_File or ODBM_File on FAT filesystem. They
can be built on a FAT filesystem, but many tests will
fail:
../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
If you intend to run only on FAT (or if using AnyDBM_File
on FAT), run Configure with the -Ui_ndbm and -Ui_dbm
options to prevent NDBM_File and ODBM_File being built.
With NTFS (and CYGWIN=ntsec), there should be no problems
even if perl was built on FAT.
"fork()" failures in io_* tests
A "fork()" failure may result in the following tests fail-
ing:
ext/IO/lib/IO/t/io_multihomed.t
ext/IO/lib/IO/t/io_sock.t
ext/IO/lib/IO/t/io_unix.t
See comment on fork in Miscellaneous below.
Specific features of the Cygwin port
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.
* 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?, nul) are
invalid as base filenames. However, they can be used
in extensions (e.g., hello.aux). Names may contain
all printable characters except these:
: * ? " < > |
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 transla-
tions applied to POSIX style pathnames).
* 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:
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.
* PerlIO
PerlIO overrides the default Cygwin Text/Binary
behaviour. A file will always treated as binary,
regardless which mode of the mount it lives on, just
like it is in UNIX. So CR/LF translation needs to be
requested in either the "open()" call like this:
open(FH, ">:crlf", "out.txt");
which will do conversion from LF to CR/LF on the out-
put, or in the environment settings (add this to your
.bashrc):
export PERLIO=crlf
which will pull in the crlf PerlIO layer which does LF
-> CRLF conversion on every output generated by perl.
* .exe
The Cygwin "stat()", "lstat()" and "readlink()" func-
tions make the .exe extension transparent by looking
for 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., cp in a makefile) the .exe is not transparent.
The install included with Cygwin automatically appends
a .exe when necessary.
* cygwin vs. windows process ids
Cygwin processes have their own pid, which is differ-
ent from the underlying windows pid. Most posix com-
pliant Proc functions expect the cygwin pid, but sev-
eral Win32::Process functions expect the winpid. E.g.
$$ is the cygwin pid of /usr/bin/perl, which is not
the winpid. Use "Cygwin::winpid_to_pid()" and "Cyg-
win::winpid_to_pid()" to translate between them.
* "chown()"
On WinNT "chown()" can change a file's user and group
IDs. On Win9x "chown()" is a no-op, although this is
appropriate 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).
The Cygwin "chroot()" implementation has holes (it can
not restrict file access by native Win32 programs).
Inplace editing "perl -i" of files doesn't work with-
out doing a backup of the file being edited "perl
-i.bak" because of windowish restrictions, therefore
Perl adds the suffix ".bak" automatically if you use
"perl -i" without specifying a backup extension.
Using "fork()" after loading multiple dlls may fail
with an internal cygwin error like the following:
C:\CYGWIN\BIN\PERL.EXE: *** couldn't allocate memory 0x10000(4128768) for 'C:\CYGWIN\LIB\PERL5\5.6.1\CYGWIN-MULTI\AUTO\SOCKET\SOCKET.DLL' alignment, Win32 error 8
200 [main] perl 377147 sync_with_child: child -395691(0xB8) died before initialization with status code 0x1
1370 [main] perl 377147 sync_with_child: *** child state child loading dlls
Use the rebase utility to resolve the conflicting dll
addresses. The rebase package is included in the Cyg-
win netrelease. Use setup.exe from http://www.cyg-
win.com/setup.exe to install it and run rebaseall.
Prebuilt methods:
"Cwd::cwd"
Returns current working directory.
"Cygwin::pid_to_winpid"
Translates a cygwin pid to the corresponding Windows
pid (which may or may not be the same).
"Cygwin::winpid_to_pid"
Translates a Windows pid to the corresponding cygwin
pid (if any).
INSTALL PERL ON CYGWIN
This will install Perl, including man pages.
make install 2>&1 | 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 ON CYGWIN
These are the files in the Perl release that contain ref-
erences 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 (listing not updated yet).
Documentation
INSTALL README.cygwin README.win32 MANIFEST
Changes Changes5.005 Changes5.004 Changes5.6
pod/perl.pod pod/perlport.pod pod/perlfaq3.pod
pod/perldelta.pod pod/perl5004delta.pod pod/perl56delta.pod
pod/perlhist.pod pod/perlmodlib.pod perl/buildtoc pod/perltoc.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/b.t - ignore Cwd from os_extras
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)
t/lib/cygwin.t - builtin cygwin function tests
Compiled Perl Source
EXTERN.h - __declspec(dllimport)
XSUB.h - __declspec(dllexport)
cygwin/cygwin.c - os_extras (getcwd, spawn, Cygwin::winpid_to_pid,
Cygwin::pid_to_winpid)
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, pp_system with spawn
util.c - use setenv
Compiled Module Source
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/Find.pm - on remote drives stat() always sets st_nlink to 1
lib/File/Spec/Unix.pm - preserve //unc
lib/File/Temp.pm - no directory sticky bit
lib/perl5db.pl - use stdin not /dev/tty
utils/perldoc.PL - version comment
BUGS ON CYGWIN
Support for swapping real and effective user and group IDs
is incomplete. On WinNT Cygwin provides "setuid()",
"seteuid()", "setgid()" and "setegid()". However, addi-
tional Cygwin calls for manipulating WinNT access tokens
and security contexts are required.
AUTHORS
Charles Wilson , Eric Fifer
, alexander smishlajev , Steven Morlock ,
Sebastien Barre , Teun Burgers
, Gerrit P. Haase .
HISTORY
Last updated: 2005-02-11
perl v5.8.8 2006-01-07 PERLCYGWIN(1)