PERLCYGWIN(1)

💖 PERLCYGWIN(1) 💖

okay bestie, welcome to perlcygwin, straight outta the Perl Programmers Reference Guide ✨ it's giving "let's get Perl running on Cygwin together" and honestly? we're gonna slay it 💅

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🌸 NAME 🌸

perlcygwin — Perl for Cygwin 🦋

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✨ SYNOPSIS ✨

This doc is gonna walk you through configuring, making, testing and installing Perl on Cygwin 🎀 It also spills the tea on Cygwin features that mess with how Perl behaves at runtime, fr fr.

NOTE: bestie, there are pre-built Perl packages already available for Cygwin, and a version of Perl ships in the normal Cygwin install 👑 If you don't need to customize the configuration, pls consider just using one of those packages, it's so much easier 😭

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🧚 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 environment these programs expect. Iconic behaviour honestly.

More info about this project lives at:

https://www.cygwin.com/

You're gonna need a recent net or commercial release of Cygwin ⭐

At the time this document was last updated, Cygwin 3.0.7 was current 👑

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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, so don't stress if you're just vibing with regular Perl.

NOTE: The binaries that get built will run on all Win32 versions 🎀 They do not depend on your host system or your Cygwin configuration (binary/text mounts, cygserver). The only dependencies come from hard-coded pathnames like /usr/local. However, 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 not-needed Windows directories should be removed or moved to the end of your PATH.
• nroff — If you don't have nroff (which is part of the groff package), Configure will not prompt you to install man pages 😭

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💅 CONFIGURE PERL ON CYGWIN 💅

The default options gathered by Configure with the assistance of hints/cygwin.sh will build a Perl that supports dynamic loading (which requires a shared cygperl5_16.dll) ✨

This will run Configure and keep a record:

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

If you're willing to accept all the defaults, run Configure with -de 👑 However, several useful customizations are available, so maybe don't just rawdog the defaults, bestie.

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🎀 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, which is lowkey so satisfying.

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 g++ to create a dynamically loaded
library?
[none] -s
Any special flags to pass to gcc to use dynamic linking? [none] -s

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

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🌸 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're 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. As of libcrypt 1.3 (March 2016), you will need to install the libcrypt-devel package for Configure to detect crypt() 💅
• -lgdbm_compat (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 💀

• cygserver (use IPC::SysV) — A port of SysV IPC is available for Cygwin 👑

NOTE: This has not been extensively tested 🚨 In particular, d_semctl_semun is undefined because it fails a Configure test. It also creates a compile time dependency because perl.h includes <sys/ipc.h> and <sys/sem.h> (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 🧚

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⭐ 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 🎀
• -Dusemymalloc — By default Perl does not use the malloc() 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 💅
• -Uuseperlio — Undefining this symbol disables the PerlIO abstraction. PerlIO is now the default; it is not recommended to disable PerlIO 😭
• -Dusemultiplicity — 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 -Uuseithreads ✨
• -Uuse64bitint — By default Perl uses 64 bit integers. If you want to use smaller 32 bit integers, define this symbol 👑
• -Duselongdouble — gcc supports long doubles (12 bytes) 💖 However, several additional long double math functions are necessary to use them within Perl ({atan2, cos, exp, floor, fmod, frexp, isnan, log, modf, pow, sin, sqrt}l, strtold). These are not yet available with newlib, the Cygwin libc 😭
• -Uuseithreads — Define this symbol if you want not-threaded faster 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 🌳 Details can be found in the INSTALL document. This is the recommended way to build perl from sources 🎀

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🔥 MAKE ON CYGWIN 🔥

Simply run make and wait:

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

where n is the maximum number of simultaneous compilations you want 💅 omitting this parameter is the same as specifying -j1 ✨

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🌈 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 👀 and you can run the tests in parallel by instead specifying

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

where n is the maximum number of tests to run simulataneously ⚡

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 😭

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💀 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 default ntsec CYGWIN 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):

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)

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🍓 NDBM_File and ODBM_File do not work on FAT filesystems 🍓

🚨 Do not use NDBM_File or ODBM_File on a 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 no CYGWIN=nontsec), there should be no problems even if perl was built on FAT ✨

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🙈 fork() failures in io_* tests 🙈

A fork() failure may result in the following tests failing:

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 literally ate when it comes to making Win32 systems feel like UNIX, no cap. But bestie, on top of everything we already talked about, there are some little differences you need to know about. This is the super-speedrun version of portability — for the full tea, go read the Cygwin docs.

• Pathnames 🛤️

Cygwin pathnames get separated by forward (/) slashes, and Universal Naming Codes (//UNC) are supported too. Since cygwin-1.7, non-POSIX pathnames should not be used, periodt. Names can contain all printable characters.

File names are case insensitive but case preserving. A pathname that contains a backslash or a drive letter is a Win32 pathname, and it does not get the translations that POSIX style pathnames get — but cygwin will warn you about it, so pls just convert them to POSIX.

For conversion we have Cygwin::win_to_posix_path() and Cygwin::posix_to_win_path().

Since cygwin-1.7, pathnames are UTF-8 encoded. ✨

• Text/Binary 📄💾

Since cygwin-1.7, textmounts are deprecated and strongly discouraged. Don't do it.

When a file is opened it's 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 decided by the mode of the mount that underlies the file. See "Cygwin::is_binmount"(). Perl gives you a binmode() function to set binary mode on files that would otherwise be treated as text. And sysopen() with the "O_TEXT" flag sets text mode on files that would otherwise 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. That's just the rules. 😤

The text/binary issue is covered at length in the Cygwin documentation.

• PerlIO 🫶

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 UNIX. So CR/LF translation needs to be requested, either in the open() call like this:

open(FH, ">:crlf", "out.txt");

which will do conversion from LF to CR/LF on the output, or in the environment settings (add this to your .bashrc):

export PERLIO=crlf

which will pull in the crlf PerlIO layer that does LF -> CRLF conversion on every output generated by perl.

• .exe 🪟

The Cygwin stat(), lstat() and readlink() functions 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 program included with Cygwin automatically appends a .exe when necessary.

• Cygwin vs. Windows process ids 🆔

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. $$ is the cygwin pid of /usr/bin/perl, which is not the winpid. Use Cygwin::pid_to_winpid() and Cygwin::winpid_to_pid() to translate between them.

• Cygwin vs. Windows errors 😭

Under Cygwin, $^E is the same as $!. When using Win32 API Functions, use Win32::GetLastError() to get the last Windows error.

• rebase errors on fork or system 💀

Using fork() or system() out to another perl after loading multiple dlls may result in a DLL baseaddress conflict. The internal cygwin error looks like the following:

0 [main] perl 8916 child_info_fork::abort: data segment start:
parent (0xC1A000) != child(0xA6A000)

or:

183 [main] perl 3588 C:\cygwin\bin\perl.exe: *** fatal error -
unable to remap C:\cygwin\bin\cygsvn_subr-1-0.dll to same address
as parent(0x6FB30000) != 0x6FE60000 46 [main] perl 3488 fork: child
3588 - died waiting for dll loading, errno11

See <https://cygwin.com/faq/faq.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 MS Internet Explorer might help. 🙈

Use the rebase utilities to resolve the conflicting dll addresses. The rebase package is included in the Cygwin setup. Use setup.exe from <https://cygwin.com/install.html> to install it.

1. kill all perl processes and run "/bin/find <dir" -xdev -name \*.dll | /bin/rebase -OT ->> or
2. kill all cygwin processes and services, and run setup.exe.

• Miscellaneous 🎀

File locking using the "F_GETLK" command to fcntl() is a stub that returns "ENOSYS".

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 without 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.

🔮 Prebuilt methods: 🔮

"Cwd::cwd"

Returns the 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).

"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.

"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.

Cygwin::mount_table()

Returns an array of [mnt_dir, mnt_fsname, mnt_type, mnt_opts].

perl -e 'for $i (Cygwin::mount_table) {print join(" ",@$i),"\n";}'
/bin c:\cygwin\bin system binmode,cygexec
/usr/bin c:\cygwin\bin system binmode
/usr/lib c:\cygwin\lib system binmode
/ c:\cygwin system binmode
/cygdrive/c c: system binmode,noumount
/cygdrive/d d: system binmode,noumount
/cygdrive/e e: system binmode,noumount

"Cygwin::mount_flags"

Returns the mount type and flags for a specified mount point. A comma-separated string of mntent->mnt_type (always "system" or "user"), then the mntent->mnt_opts, where the first is always "binmode" or "textmode".

system|user,binmode|textmode,exec,cygexec,cygdrive,mixed,
notexec,managed,nosuid,devfs,proc,noumount

If the argument is "/cygdrive", then just the volume mount settings, and the cygdrive mount prefix are returned.

User mounts override system mounts. 👑

$ perl -e 'print Cygwin::mount_flags "/usr/bin"'
system,binmode,cygexec
$ perl -e 'print Cygwin::mount_flags "/cygdrive"'
binmode,cygdrive,/cygdrive

"Cygwin::is_binmount"

Returns true if the given cygwin path is binary mounted, false if the path is mounted in textmode.

"Cygwin::sync_winenv"

Cygwin does not initialize all original Win32 environment variables. See the bottom of this page <https://cygwin.com/cygwin-ug-net/setup-env.html> for "Restricted Win32 environment".

Certain Win32 programs called from cygwin programs might need some environment variable, such as e.g. ADODB needs %COMMONPROGRAMFILES%. Call Cygwin::sync_winenv() to copy all Win32 environment variables to your process and note that cygwin will warn on every encounter of non-POSIX paths.

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🌸 INSTALL PERL ON CYGWIN 🌸

This will install Perl, including man pages. Obsessed. 💖

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 directories in question.

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

📚 Documentation 📚

okay so these are all the docs that mention Cygwin, bestie — pure lore:

• 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/updateAUTHORS.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

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🛠️ Build, Configure, Make, Install 🛠️

the whole pipeline where Cygwin shows up, and why:

• 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 'pods'
• makedepend.SH — uwinfix
• regen_lib.pl — file permissions
• plan9/mkfile
• vms/descrip_mms.template
• win32/Makefile

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🧪 Tests 🧪

the test files that go "hold up, Cygwin" and do something special:

• 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't use empty path under Cygwin Perl
• t/op/time.t — no tzset()

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💻 Compiled Perl Source 💻

the C files that #ifdef'd for us, and the receipts:

• 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

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📦 Compiled Module Source 📦

same energy but for the modules, slay:

• ext/Compress-Raw-Zlib/Makefile.PL — Can't 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)

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🐚 Perl Modules/Scripts 🐚

the .pm and script glow-ups, with commentary:

• 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 'pods' dir
• lib/Pod/Perldoc/ToMan.pm — '-c' switch for pod2man
• lib/Pod/Perldoc.pm — Use 'less' 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

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🧾 Perl Module Tests 🧾

no notes attached, they just are, and they're all valid:

• 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

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💀 BUGS ON CYGWIN 💀

okay so this is the part where we hold hands. Support for swapping real and effective user and group IDs is incomplete. On WinNT Cygwin provides setuid(), seteuid(), setgid() and setegid(). However, additional Cygwin calls for manipulating WinNT access tokens and security contexts are required.

so like… it works, but it's giving unfinished. not a you problem, it's a needs-more-Cygwin-calls problem. 💅

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👑 AUTHORS 👑

the literal icons who built this, no cap, bow down:

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>.

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📜 HISTORY 📜

Last updated: 2019-11-14

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and that's the whole page bestie 🫶 this one came from perl v5.42.3, dated 2026-08-03 — the PERLCYGWIN(1) era, iconic behavior only. go forth and compile, mwah 💖✨🎀