Re: file descriptors opened as text files

["Larry Hall (RFK Partners Inc)" <lhall@rfk.com>]

At 05:08 PM 2/14/01, Jean Delvare wrote:


>> Type "mount" on your system.  What does it show?  Is the file in question
>> being written under any of these mount points?  Any of them binary?
>I think I understand the mount mechanism, and the binary vs text mode
>mount. But I don't see the point when runing out of bash. Do you pretend
>that the way I mount my drives with bash/mount changes the program
>behaviour when I run it directly from Windows ? (I can hardly believe it)

You proceed from a false supposition.

mount is a stand-alone utility.  It manipulates the way Cygwin sees the 
file system.  It has nothing to do with bash.  Since your program relies
on Cygwin and Cygwin interprets the file system through the existence or
absence of mount points, your program treats files as Cywgin would treat
the files, with or without bash.


>> Bingo.  Cygwin treats files as text by default, unless you specify a 
>> different default.  If you want your program to treat the file as binary,
>> add the appropriate flags on the appropriate calls.  Whamo!  Your problem
>> is solved.
>I hope so. That's also the way I see the thing. The question is : What
>flags ?
>When using handles, I can solve the problem with fopen(f,"rb") instead of
>fopen(f,"r"). And it works. But I read the whole read(2) man page (on
>Linux, it doesn't exist on Cygwin) and nowhere I saw a flag that force
>binary mode. Can you help ?


On Linux/UNIX, there's no difference between "binary" and "text" files, so
the added flag is inconsequential.  However, it is standard so whether the
docs mention it or not, its legal and will get you precisely what you want,
in a portable way.


>Anyway, thanks *a lot* for the help so far.


Happy to be of service.



Larry Hall                              lhall@rfk.com
RFK Partners, Inc.                      http://www.rfk.com
118 Washington Street                   (508) 893-9779 - RFK Office
Holliston, MA 01746                     (508) 893-9889 - FAX
                                        


--
Want to unsubscribe from this list?
Check out: http://cygwin.com/ml/#unsubscribe-simple