Changing directories from a C console program

[oddstray]

Hi,

I'm using WinXP. I wrote a short C utility in which I want to change
directories and run programs. When I use the system() method and pass
in the same command that works in a cmd.exe session, it claims "Unable
to locate the directory". This happens for directories with and
without spaces in their names. Can anyone tell me what's wrong?
Thanks.


B


Here's the code snippet that fails:

if( _chdir( "C:" ) != 0 )
printf( "Unable to locate the directory: %s\n", "C:" );
else
system( "dir *.*");

// WORKS THIS FAR

if( _wchdir( "cd Perl" ) != 0 )
printf( "Unable to locate the directory: %s\n", "Perl" );
else
system( "dir *.*");

if( _wchdir( "cd C:\\Perl" ) != 0 )
printf( "Unable to locate the directory: %s\n", "C:\\Perl" );
else
system( "dir *.*");

// 'UNABLE TO LOCATE' EITHER OF THESE ALTHOUGH THIS DIRECTORY DOES
EXIST

[Jack Klein]

Re: Changing directories from a C console program

On 26 Aug 2004 17:57:50 -0700, oddstray@gmail. com (oddstray) wrote in
comp.lang.c:
[color=blue]
> Hi,
>
> I'm using WinXP. I wrote a short C utility in which I want to change
> directories and run programs. When I use the system() method and pass
> in the same command that works in a cmd.exe session, it claims "Unable
> to locate the directory". This happens for directories with and
> without spaces in their names. Can anyone tell me what's wrong?
> Thanks.[/color]

Not here, we can't. The standard C language has no support for
directories at all. Not all systems have them and they are
implemented in vastly different ways on some platforms that do.
[color=blue]
> Here's the code snippet that fails:
>
> if( _chdir( "C:" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "C:" );
> else
> system( "dir *.*");
>
> // WORKS THIS FAR
>
> if( _wchdir( "cd Perl" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "Perl" );
> else
> system( "dir *.*");
>
> if( _wchdir( "cd C:\\Perl" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "C:\\Perl" );
> else
> system( "dir *.*");
>
> // 'UNABLE TO LOCATE' EITHER OF THESE ALTHOUGH THIS DIRECTORY DOES
> EXIST[/color]

There are no functions named "_chdir" or "_wchdir" in the standard C
library, they are extensions provided by your compiler. You need to
ask about this in one of Microsoft's support groups in the
news:microsoft. public.vc.* family, or a group like
news:comp.os.ms-windows.program mer.win32.

It is a Windows issue, not a C language one.

--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://www.eskimo.com/~scs/C-faq/top.html
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.l earn.c-c++

http://www.contrib.andrew.cmu.edu/~ajo/docs/FAQ-acllc.html

[Keith Thompson]

Re: Changing directories from a C console program

oddstray@gmail. com (oddstray) writes:[color=blue]
> I'm using WinXP. I wrote a short C utility in which I want to change
> directories and run programs. When I use the system() method and pass
> in the same command that works in a cmd.exe session, it claims "Unable
> to locate the directory". This happens for directories with and
> without spaces in their names. Can anyone tell me what's wrong?
> Thanks.
>
>
> B
>
>
> Here's the code snippet that fails:
>
> if( _chdir( "C:" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "C:" );
> else
> system( "dir *.*");
>
> // WORKS THIS FAR
>
> if( _wchdir( "cd Perl" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "Perl" );
> else
> system( "dir *.*");
>
> if( _wchdir( "cd C:\\Perl" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "C:\\Perl" );
> else
> system( "dir *.*");
>
> // 'UNABLE TO LOCATE' EITHER OF THESE ALTHOUGH THIS DIRECTORY DOES
> EXIST[/color]

We don't know. The _chdir() and _wchdir() functions aren't defined in
standard C; neither are directories, for that matter. You might try a
Windows-specific newsgroup. (But first, you might ask yourself
whether _wchdir() expects a directory name or a command string.)

--
Keith Thompson (The_Other_Keit h) kst-u@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.

[jacob navia]

Re: Changing directories from a C console program

oddstray wrote:[color=blue]
> Hi,
>
> I'm using WinXP. I wrote a short C utility in which I want to change
> directories and run programs. When I use the system() method and pass
> in the same command that works in a cmd.exe session, it claims "Unable
> to locate the directory". This happens for directories with and
> without spaces in their names. Can anyone tell me what's wrong?
> Thanks.
>
>
> B
>
>
> Here's the code snippet that fails:
>
> if( _chdir( "C:" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "C:" );
> else
> system( "dir *.*");
>
> // WORKS THIS FAR
>
> if( _wchdir( "cd Perl" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "Perl" );
> else
> system( "dir *.*");
>
> if( _wchdir( "cd C:\\Perl" ) != 0 )
> printf( "Unable to locate the directory: %s\n", "C:\\Perl" );
> else
> system( "dir *.*");
>
> // 'UNABLE TO LOCATE' EITHER OF THESE ALTHOUGH THIS DIRECTORY DOES
> EXIST[/color]

wchdir expects a wide character set string, not a multi byte one.
Hence, it doesn't find any directory you pass it.

Rule:
Use the documentation when something doesn't work.

[Alan Balmer]

Re: Changing directories from a C console program

On 26 Aug 2004 17:57:50 -0700, oddstray@gmail. com (oddstray) wrote:
[color=blue]
>
>I'm using WinXP. I wrote a short C utility in which I want to change
>directories and run programs. When I use the system() method and pass
>in the same command that works in a cmd.exe session, it claims "Unable
>to locate the directory". This happens for directories with and
>without spaces in their names. Can anyone tell me what's wrong?
>Thanks.[/color]

Off topic here. Try a Windows programming group. However, I note that
you have one method which works - why not use it?

{OT} I wouldn't expect the system calls to work. You spawn a shell,
change directory in that shell, then close the shell and return to the
program you spawned it from. {/OT]

--
Al Balmer
Balmer Consulting
removebalmercon sultingthis@att .net

[Kenneth Brody]

Re: Changing directories from a C console program

oddstray wrote:
[...][color=blue]
> if( _wchdir( "cd Perl" ) != 0 )[/color]
[...]

Do you really have a directory called "cd Perl"?

If so, then something else is wrong, and you'll need to ask help in a
Windows-related group.

If not, then I hope you see the problem now.

--
+-------------------------+--------------------+-----------------------------+
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