[Bug 18617] New: Regedit can't import registry from standard input

http://bugs.winehq.org/show_bug.cgi?id=18617

Summary: Regedit can't import registry from standard input
           Product: Wine
           Version: 1.1.22
          Platform: PC-x86-64
        OS/Version: Linux
            Status: NEW
          Keywords: regression, source, testcase
          Severity: normal
          Priority: P2
         Component: programs
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

Created an attachment (id=21305)
 --> (http://bugs.winehq.org/attachment.cgi?id=21305)
Sample test program

Importing file like this works:
-------------------
REGEDIT4

[HKEY_CURRENT_USER\Software\Wine\Direct3D]
"UseGLSL"="enabled"
-------------------

However this command doesn't work:
echo -e
'REGEDIT4\n[HKEY_CURRENT_USER\Software\Wine\Direct3D]\n"UseGLSL"="enabled"\n'
| wine regedit -

This is due to this piece of code:
        if (fread( s, 2, 1, reg_file) == 1)
        {
            if (s[0] == 0xff && s[1] == 0xfe)
            {
                processRegLinesW(reg_file);
            } else
            {
->              rewind(reg_file);
                processRegLinesA(reg_file);
            }
        }

According to MS doing rewind on stdin clears the buffer. Sample program
attached.