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[PATCH] perl.h, README.cygwin: Cygwin O_TEXT <> O_BINARY issue

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From:
Gerrit P. Haase
Date:
May 31, 2003 05:07
Subject:
[PATCH] perl.h, README.cygwin: Cygwin O_TEXT <> O_BINARY issue
Message ID:
179860591535.20030531141207@familiehaase.de
Hallo perl5-porters,

  Cygwin has O_TEXT <> O_BINARY, with this patch it will no longer
  default to PERLIO_USING_CRLF which causes several problems with
  existing scripts and other issues with LF -> CRLF translation.
  If it is needed, it is still possible to pull it in with the
  environment setting PERLIO=crlf.


$ diff -ur perl.h~ perl.h
--- perl.h~     2003-05-30 17:36:43.000000000 +0200
+++ perl.h      2003-05-30 19:06:54.000000000 +0200
@@ -4092,7 +4092,7 @@
 #if O_TEXT != O_BINARY
     /* If you have different O_TEXT and O_BINARY and you are a CLRF shop,
      * that is, you are somehow DOSish. */
-#   if defined(__BEOS__) || defined(__VOS__)
+#   if defined(__BEOS__) || defined(__VOS__) || defined(__CYGWIN__)
     /* BeOS has O_TEXT != O_BINARY but O_TEXT and O_BINARY have no effect;
      * BeOS is always UNIXoid (LF), not DOSish (CRLF). */
     /* VOS has O_TEXT != O_BINARY, and they have effect,

  
  
$ diff -ur README.cygwin~ README.cygwin
--- README.cygwin~      2003-05-31 13:05:28.000000000 +0200
+++ README.cygwin       2003-05-31 13:49:57.000000000 +0200
@@ -31,7 +31,7 @@
 
 A recent net or commercial release of Cygwin is required.
 
-At the time this document was last updated, Cygwin 1.3.12 was current.
+At the time this document was last updated, Cygwin 1.3.22 was current.
 
 
 =head2 Cygwin Configuration
@@ -177,13 +177,13 @@
 
 =item * C<-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.
+By default Perl uses the C<malloc()> included with the Perl source.  If you
+want to force Perl to build with the system C<malloc()> undefine this symbol.
 
 =item * C<-Uuseperlio>
 
-Undefining this symbol disables the PerlIO abstraction, which is now the
-default.
+Undefining this symbol disables the PerlIO abstraction, PerlIO is now the
+default, it is not recommended to disable PerlIO.
 
 =item * C<-Dusemultiplicity>
 
@@ -218,7 +218,8 @@
 =item * C<-Dmksymlinks>
 
 Use this to build perl outside of the source tree.  This works with Cygwin.
-Details can be found in the F<INSTALL> document.
+Details can be found in the F<INSTALL> document.  This is the recommended 
+way to build perl form sources.
 
 =back
 
@@ -231,10 +232,10 @@
 =item * I<dlsym()>
 
 I<ld2> is needed to build dynamic libraries, but it does not exist
-when dlsym() checking occurs (it is not created until `C<make>' runs).
+when C<dlsym()> checking occurs (it is not created until `C<make>' runs).
 You will see the following message:
 
-  Checking whether your dlsym() needs a leading underscore ...
+  Checking whether your C<dlsym()> 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.
@@ -367,9 +368,9 @@
 With NTFS (and CYGWIN=ntsec), there should be no problems even if
 perl was built on FAT.
 
-=head2 fork() failures in io_* tests
+=head2 C<fork()> failures in io_* tests
 
-A fork() failure may result in the following tests failing:
+A C<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
@@ -405,20 +406,37 @@
 
 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() function to set binary mode on files
-that otherwise would be treated as text.  sysopen() with the C<O_TEXT>
+mode for an C<open()> is determined by the mode of the mount that underlies
+the file.  Perl provides a C<binmode()> function to set binary mode on files
+that otherwise would be treated as text.  C<sysopen()> with the C<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.
+C<lseek()>, C<tell()> and C<sysseek()> only work with files opened in binary mode.
 
 The text/binary issue is covered at length in the Cygwin documentation.
 
+=item * 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 n UNIX.  So CR/LF translation needs to be requested in 
+either the C<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 which does LF -> CRLF conversion 
+on every output generated by perl.
+
 =item * F<.exe>
 
-The Cygwin stat(), lstat() and readlink() functions make the F<.exe>
+The Cygwin C<stat()>, C<lstat()> and C<readlink()> functions make the F<.exe>
 extension transparent by looking for F<foo.exe> when you ask for F<foo>
 (unless a F<foo> also exists).  Cygwin does not require a F<.exe>
 extension, but I<gcc> adds it automatically when building a program.
@@ -426,27 +444,27 @@
 in a makefile) the F<.exe> is not transparent.  The I<install> included
 with Cygwin automatically appends a F<.exe> when necessary.
 
-=item * chown()
+=item * C<chown()>
 
-On WinNT chown() can change a file's user and group IDs.  On Win9x chown()
+On WinNT C<chown()> can change a file's user and group IDs.  On Win9x C<chown()>
 is a no-op, although this is appropriate since there is no security model.
 
 =item * Miscellaneous
 
-File locking using the C<F_GETLK> command to fcntl() is a stub that
+File locking using the C<F_GETLK> command to C<fcntl()> is a stub that
 returns C<ENOSYS>.
 
-Win9x can not rename() an open file (although WinNT can).
+Win9x can not C<rename()> an open file (although WinNT can).
 
-The Cygwin chroot() implementation has holes (it can not restrict file
+The Cygwin C<chroot()> implementation has holes (it can not restrict file
 access by native Win32 programs).
 
 Inplace editing C<perl -i> of files doesn't work without doing a backup 
 of the file being edited C<perl -i.bak> because of windowish restrictions,
-therefore Perl adds the C<.bak> automatically if you use C<perl -i> 
+therefore Perl adds the suffix C<.bak> automatically if you use C<perl -i> 
 without specifying a backup extension.
 
-Using fork() after loading multiple dlls may fail with an internal cygwin
+Using C<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
@@ -456,7 +474,7 @@
 
 Use the rebase utility to resolve the conflicting dll addresses.  The
 rebase package is included in the Cygwin netrelease.  Use setup.exe from
-F<http://www.cygwin.com/setup.exe> to install it.
+F<http://www.cygwin.com/setup.exe> to install it and run rebaseall.
 
 =back
 
@@ -545,7 +563,7 @@
                         - 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/Find.pm      - on remote drives C<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
@@ -556,7 +574,7 @@
 =head1 BUGS ON CYGWIN
 
 Support for swapping real and effective user and group IDs is incomplete.
-On WinNT Cygwin provides setuid(), seteuid(), setgid() and setegid().
+On WinNT Cygwin provides C<setuid()>, C<seteuid()>, C<setgid()> and C<setegid()>.
 However, additional Cygwin calls for manipulating WinNT access tokens
 and security contexts are required.
 

#Gerrit
-- 
=^..^=


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