OS.SYSTEM ERROR !!!

[Terry Reedy]

Blubaugh, David A. wrote:
> To All, 
> 
> 
> I have been attempting to execute the following program within the
> Python environment:
> 
> Myprogram.exe, which means this is an executable file!!
> 
> I would usually execute this program (with the appropriate arguments) by
> going to following directory within MS-DOS (Windows XP):
> 
> C:\myprogramfolder\run> Myprogram.exe 1 1 acc 0
> 
> The executable would execute perfectly.

Because you execute it in the necessary directory.

> However, when I would try to execute the following lines of source code
> within a python script file:
> 
> import os
> 
> os.system(r"C:\myprogramfolder\run\Myprogram.exe 1 1 acc 0") 

This does not execute it in the proper directory.
os.getcwd() will tell you where you are -- mostly likely .../Pythonx.y.

Try:
os.chdir("C:/myprogramfolder/run") # / works fine, and without r prefix
os.system("Myprogram.exe 1 1 acc 0")

> The executable file would start to execute until it would print an error
> stating that it cannot use a (.dat) file, which is located under the
> following directory:  
> 
> C:\myprogramfolder\run\inputs\io\control.dat
> 
> 
> I believe I may be missing something here that prevents the executable
> file working within python from utilizing this (.dat).  The printed
> final error is the following:
> 
> ERROR opening inputs/io/control.dat
> 
> Does anyone know what that could be ??

That file does not exist in the Pythonx.y directory where the program 
starts ;-).

tjr