Comment author: administrator

I have done my own experiment and I saw translation to \r\n:

let _ = set_binary_mode_out stdout true in
print_string "one\ntwo"

I checked with emacs hexl-mode and I saw that \r\n is present there.

Ah, I installed cygwin in DOS mode!!! This must be it. But this still argues that set_binary_mode_out should do something, because you do not know how cygwin was installed.

But here is the actual thing that hit me:

If you try to use camlp4 the ocamlc compiler crashes:

ocamlc -pp "camlp4o pa_macro.cmo" -I +camlp4 -c foo.ml

• this crashes because the preprocessor outputs the binary format AST to stdout, which ocamlc redirects to a temporary file (in driver/pparse.ml). The camlp4o command uses pr_dump.cmo by default and you can see right at the top of camlp4/meta/pr_dump.ml that it uses set_binary_mode_out to set stdout to binary.

I can work around this problem in two ways. I can add pr_o.cmo to the camlp4o command above, which will make camlp4 print Ocaml source not binary AST. Or, I can change ocamlc to not pipe the results of the pretty printer to stdout, but send it directly to the temporary file (change format string in driver/pparse.ml to use format string "%s %s -o %s"). Clearly in this later case the code in pr_dump.ml is able to set the binary mode because it uses open_out_bin instead of set_binary_mode_out.

As you can see, if you do not fix the set_binary_mode_out (which I think should be done), we must fix how the preprocessor is invoked in ocamlc.

George.

-----Original Message-----
From: Michel Mauny [mailto:michel@mauny.net]
Sent: Monday, October 24, 2005 10:49 AM
To: necula@cs.berkeley.edu
Cc: caml@pauillac.inria.fr; caml-bugs@pauillac.inria.fr
Subject: Re: [Caml-devel] Bug in set_binary_mode out for
cygwin (#3818)

George,

As you noticed, set_binary_mode_out has no effect on Cygwin.

However, I'm not sure this is the source of your problem:
stdout seems to be already in "binary mode" in Cygwin.
Printing "\n" | od -c shows no translation of newlines, while
translations of "\n" into "\r\n"
do occur when printing to files.

Do you have a small example showing the bug in camlp4?

Cheers,

-- Michel

necula@cs.berkeley.edu wrote:

Full_Name: George Necula
Version: 3.08.4
OS: Win XP/cygwin
Submission from: adsl-63-204-134-90.dsl.snfc21.pacbell.net
(63.204.134.90)

I have discovered that "set_binary_mode_out c true" has no
effect on
cygwin. In
fact, this function does nothing except when compiling for Windows
(but not for
cygwin).

This is a big problem because it prevents the use of the -pp option
for ocamlc
on cygwin. camlp4 will print the AST to stdout and will use
set_binary_mode_out.
When ocamlc reads in the AST it segfaults. The workaround is to make
sure you
add pr_o.cmo to the preprocessor command, to ensure that
Ocaml source
is piped
to stdout.

---

Caml-devel mailing list
Caml-devel@yquem.inria.fr
http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-devel

--
Michel

Mail: michel@mauny.net
Tél: (+33) 1 3080 9638 (Home)
(+33) 8 7379 9638 (VoIP@Home)
(+33) 6 7319 3516 (Cell.)
(+33) 1 4552 5388 (ENSTA)
(+33) 1 3963 5796 (INRIA)

Comment author: administrator

George,

As you noticed, set_binary_mode_out has no effect on Cygwin.

However, I'm not sure this is the source of your problem: stdout seems
to be already in "binary mode" in Cygwin. Printing "\n" | od -c shows
no translation of newlines, while translations of "\n" into "\r\n"
do occur when printing to files.

Do you have a small example showing the bug in camlp4?

Cheers,

-- Michel

necula@cs.berkeley.edu wrote:

Full_Name: George Necula
Version: 3.08.4
OS: Win XP/cygwin
Submission from: adsl-63-204-134-90.dsl.snfc21.pacbell.net (63.204.134.90)

I have discovered that "set_binary_mode_out c true" has no effect on
cygwin. In
fact, this function does nothing except when compiling for Windows
(but not for
cygwin).

This is a big problem because it prevents the use of the -pp option
for ocamlc
on cygwin. camlp4 will print the AST to stdout and will use
set_binary_mode_out.
When ocamlc reads in the AST it segfaults. The workaround is to make
sure you
add pr_o.cmo to the preprocessor command, to ensure that Ocaml source
is piped
to stdout.

---

Caml-devel mailing list
Caml-devel@yquem.inria.fr
http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-devel

--
Michel

Mail: michel@mauny.net
Tél: (+33) 1 3080 9638 (Home)
(+33) 8 7379 9638 (VoIP@Home)
(+33) 6 7319 3516 (Cell.)
(+33) 1 4552 5388 (ENSTA)
(+33) 1 3963 5796 (INRIA)

Comment author: administrator

Merci beaucoup! Ca marche.

George.

-----Original Message-----
From: Michel Mauny [mailto:caml-bugs@pauillac.inria.fr]
Sent: Tuesday, October 25, 2005 1:47 PM
To: necula@cs.berkeley.edu
Subject: Re: Bug in set_binary_mode out for cygwin (#3818)

I have discovered that "set_binary_mode_out c true" has no
effect on cygwin.
In
fact, this function does nothing except when compiling for Windows
(but not
for
cygwin).

Right. I activated set_binary_mode_out (as well as the predicate
caml_channel_binary_mode) on Cygwin.

The patch is easy:

diff -r1.71 byterun/io.c
125c125
< #ifdef _WIN32

#if defined(_WIN32) || defined(CYGWIN)
516c516
< #ifdef _WIN32

---

#if defined(_WIN32) || defined(CYGWIN)

then make clean', configure' and rebuild ocaml.

-- Michel

Comment author: administrator

I have discovered that "set_binary_mode_out c true" has no effect on cygwin.
In
fact, this function does nothing except when compiling for Windows (but not
for
cygwin).

Right. I activated set_binary_mode_out (as well as the predicate
caml_channel_binary_mode) on Cygwin.

The patch is easy:

diff -r1.71 byterun/io.c
125c125
< #ifdef _WIN32

#if defined(_WIN32) || defined(CYGWIN)
516c516
< #ifdef _WIN32

#if defined(_WIN32) || defined(CYGWIN)

then make clean', configure' and rebuild ocaml.

-- Michel

Comment author: administrator

Don't do the suggested change in driver/pparse.ml, it would break using sed as
a
preprocessor. -DD

Fixed 2005-10-25 -MM