Trying to understand behavior of current directory and PATH variable.

The PATH variable on my machine is set to

C:\Perl64\site\bin;C:\Perl64\bin;C:\Windows\System32;C:\Program Files\Java\jdk1.7\bin;C:\Program Files (x86)\Notepad++;


I have a batch file (batchfile.bat) with the following commands -
dir
path
notepad++ source.frm -n2150
PAUSE

When I double click the batch file, I get the following output.

Code:

C:\ExcelExperiments>dir
 Volume in drive C has no label.
 Volume Serial Number is FC18-1C2F

 Directory of C:\ExcelExperiments

04/02/2012  12:42 PM    <DIR>          .
04/02/2012  12:42 PM    <DIR>          ..
04/02/2012  12:43 PM                45 batchfile.bat
04/02/2012  12:32 PM                32 Commands.txt
04/02/2012  12:28 PM            16,793 Excelfile.xlsx
03/09/2012  12:44 PM           308,196 source.frm
               4 File(s)        325,066 bytes
               2 Dir(s)  858,609,614,848 bytes free

C:\ExcelExperiments>path
PATH=C:\Perl64\site\bin;C:\Perl64\bin;C:\Windows\System32;C:\Program Files\Java\jdk1.7\bin;C:\Program Files (x86)\Notepad++;

C:\ExcelExperiments>notepad++ source.frm -n2150

C:\ExcelExperiments>PAUSE
Press any key to continue . . .

So far so good. Now, in the Excelfile.xlsx which is part of the current directory, I have a hyperlink that links to the batch file. However, when I click on this hyperlink, the current directory somehow changes to the Documents directory. Also, an additional entry is made temporarily to the PATH variable-

Code:

C:\Users\owner\Documents>dir
 Volume in drive C has no label.
 Volume Serial Number is FC18-1C2F

 Directory of C:\Users\owner\Documents

03/20/2012  04:54 PM    <DIR>          .
03/20/2012  04:54 PM    <DIR>          ..
02/08/2012  10:11 AM    <DIR>          Aptana Studio 3 Workspace
02/16/2012  03:37 PM    <DIR>          My Kindle Content
03/19/2012  11:05 AM    <DIR>          My Meetings
02/22/2012  01:43 PM    <DIR>          NetBeansProjects
02/16/2012  04:04 PM    <DIR>          SQL Server Management Studio
02/16/2012  04:02 PM    <DIR>          Visual Studio 2005
03/12/2012  12:06 PM    <DIR>          Visual Studio 2008
03/12/2012  12:23 PM    <DIR>          Visual Studio 2010
               0 File(s)              0 bytes
              10 Dir(s)  858,609,233,920 bytes free

C:\Users\owner\Documents>path
PATH=C:\Program Files (x86)\Microsoft Office\Office14\;C:\Perl64\site\bin;C:\Perl64\bin;C:\Windows\System32;C:\Program Files\Java\jdk1.7\bin;C:\Program Files (x86)\Notepad++;

C:\Users\owner\Documents>notepad++ source.frm -n2150

C:\Users\owner\Documents>PAUSE

How to prevent this changing of the current directory? Also, why is the additional entry made to the PATH variable?

Duzzy said:

One way around this is to change the directory before running the other cmds. The following code will change to the directory that the batch file is launched in.

Code:

cd "%~dp0"

Thanks for this tip. I still don't understand why the current directory changes though.