Broken stdio using sh.exe?

[robert dot jan dot schutten at philips dot com]

Short description:
------------------

stdio seems to be broken when communicating from bash.exe to sh.exe.

How to reproduce the problem:
-----------------------------

5 files are needed:

1) A small C file, called readbin.c.
   It reads 8 bytes from stdin and prints the hexadecimal 
   values of the characters that are read.

-- start of readbin.c --

#include <stdlib.h>
#include <stdio.h>

#define NUM_READ 8

int
main (int argc, char *argv[])
{
    FILE *file_ptr = stdin;
    unsigned char buffer[8];
    size_t num_read;
    int i;

    /* read NUM_READ bytes and print values */
    num_read = fread (buffer, sizeof(unsigned char), NUM_READ, file_ptr);
    if (num_read == NUM_READ) {
        for (i = 0; i < NUM_READ; i++) {
             printf ("%2x ", (int)buffer[i]);
        }
        printf ("\n");
    } else {
        fprintf (stderr, "%d bytes read, %d expected\n", num_read, NUM_READ);
    }

    return EXIT_SUCCESS;
}

-- end of readbin.c --

2) The excutable readbin.exe, built with:

schutten@PC6868 ~/tmp
$ gcc -o readbin readbin.c

3) I have a small binary file, called test.bin, 
   on which the od gives:

schutten@PC6868 ~/tmp
$ od -t x1 test.bin
0000000 61 62 63 64 1a 61 62 63 64 0a
0000012

4) There is one shell script that calls readbin.exe via bash:

schutten@PC6868 ~/tmp
$ cat readbin.bash
#!/bin/bash
./readbin

5) There is one shell script that calls readbin.exe via sh:

schutten@PC6868 ~/tmp
$ cat readbin.sh
#!/bin/sh
./readbin

The problem:
------------

Using bash to read from stdin works as expected:

schutten@PC6868 ~/tmp
$ cat test.bin | ./readbin.bash
61 62 63 64 1a 61 62 63

Using sh to read from stdin stops after the ^Z (hex: 1a) character:

schutten@PC6868 ~/tmp
$ cat test.bin | ./readbin.sh
4 bytes read, 8 expected

On other operating systems (linux) both shell scripts work as expected.
Since all our shell scripts use /bin/sh, this problem occurs a lot
in our system (we want to work truely multi-platform, we use
shell scripts for all our exectables that automagically start the
correct executable in a certain platform).

Workaround:
-----------

Rename sh.exe to whatever you like.
Make a link from sh.exe to bash.exe.
This makes that all our shell scripts work again...

My system:
----------

schutten@PC6868 ~/tmp
$ /bin/cygcheck -s

Cygnus Win95/NT Configuration Diagnostics
Current System Time: Tue Mar  6 11:08:41 2001

WinNT Ver 5.0 build 2195 Service Pack 1

Path:   /home/local/bin
        /usr/local/bin
        /usr/bin
        /bin
        //c/Progra~1/Networ~1/PGPNT
        //c/Progra~1/MiKTeX/texmf/miktex/bin

SysDir: C:\WINNT\System32
WinDir: C:\WINNT

PWD = `/home/local/tmp'
CYGWIN = `ntsec tty'
USER = `schutten'
MAKE_MODE = `unix'
HOME = `/home/local'

Use `-r' to scan registry

c:  hd  NTFS    5726Mb  72% CP CS UN PA FC
f:  fd           N/A    N/A
h:  net Samba  43308Mb  47% CP CS              schutten
i:  net Samba  33640Mb  89%          PA        schutten
q:  net NTFS   42154Mb  83% CP CS UN PA FC
s:  net Samba  16820Mb  50% CP CS              softtv

C:\cygwin\bin  /usr/bin  user    binmode
C:\cygwin\lib  /usr/lib  user    binmode
C:\cygwin  /        user    binmode

Found: C:\cygwin\bin\bash.exe
Found: C:\cygwin\bin\cat.exe
Found: C:\cygwin\bin\cpp.exe
Found: C:\cygwin\bin\find.exe
Found: \bin\find.exe
Found: C:\cygwin\bin\gcc.exe
Found: C:\cygwin\bin\gdb.exe
Found: C:\cygwin\bin\ld.exe
Found: C:\cygwin\bin\ls.exe
Found: C:\cygwin\bin\make.exe
Found: C:\cygwin\bin\sh.exe

   56k 2000/12/03 C:\cygwin\bin\cygbz21.0.dll
   82k 2001/01/21 C:\cygwin\bin\cygform5.dll
   18k 2000/10/23 C:\cygwin\bin\cyggdbm.dll
   17k 2001/01/07 C:\cygwin\bin\cyghistory4.dll
   14k 2000/10/23 C:\cygwin\bin\cygintl.dll
   81k 2000/12/05 C:\cygwin\bin\cygitcl30.dll
   35k 2000/12/05 C:\cygwin\bin\cygitk30.dll
   45k 2000/10/22 C:\cygwin\bin\cygjbig1.dll
  119k 2000/10/23 C:\cygwin\bin\cygjpeg6b.dll
   53k 2001/01/21 C:\cygwin\bin\cygmenu5.dll
  414k 2001/01/21 C:\cygwin\bin\cygncurses++5.dll
  299k 2001/01/21 C:\cygwin\bin\cygncurses5.dll
   34k 2001/01/21 C:\cygwin\bin\cygpanel5.dll
  163k 2001/02/03 C:\cygwin\bin\cygpng2.dll
  108k 2001/01/07 C:\cygwin\bin\cygreadline4.dll
  390k 2000/12/05 C:\cygwin\bin\cygtcl80.dll
    5k 2000/12/05 C:\cygwin\bin\cygtclpip80.dll
   10k 2000/12/05 C:\cygwin\bin\cygtclreg80.dll
  243k 2000/10/23 C:\cygwin\bin\cygtiff3.dll
  623k 2000/12/05 C:\cygwin\bin\cygtk80.dll
   41k 2000/11/20 C:\cygwin\bin\cygXpm-noX4.dll
   45k 2000/11/20 C:\cygwin\bin\cygXpm-X4.dll
   49k 2001/02/03 C:\cygwin\bin\cygz.dll
  615k 2001/01/31 C:\cygwin\bin\cygwin1.dll
    Cygwin DLL version info:
        dll major: 1001
        dll minor: 8
        dll epoch: 19
        dll bad signal mask: 19005
        dll old termios: 5
        dll malloc env: 28
        api major: 0
        api minor: 34
        shared data: 3
        dll identifier: cygwin1
        mount registry: 2
        cygnus registry name: Cygnus Solutions
        cygwin registry name: Cygwin
        program options name: Program Options
        cygwin mount registry name: mounts v2
        cygdrive flags: cygdrive flags
        cygdrive prefix: cygdrive prefix
        cygdrive default prefix:
        build date: Wed Jan 31 10:08:38 EST 2001
        shared id: cygwin1S3

Use -h to see help about each section

--
With kind regards,
     Robert Jan Schutten
  - "Imagination is more important than knowledge" - Einstein -
--
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