Starting an executable using /affinity in cmd.exe (Windows XP) - command-line

Question

I have a program that I'm trying to use which crashes often, and one of the fixes for this is to set it to only use one processor.
I can easily do this through task manager manually, but I'd much prefer a solution along the lines of doubleclicking a shortcut.
I've tried making at .bat file with this line of code:
C:\Windows\System32\cmd.exe /C start /affinity 1 KSP.exe
However, it just refuses to run. removing the /C switch only starts the cmdbox.
Trying to type /affinity 1 KSP.exe into the cmdbox (Thankfully the cmdbox starts with the directory the .bat file is in, which is the same folder that the .exe isin so no problems there) simply gives this error:
Invalid switch - "/affinity".

Answer 1

I just ran into this same issue myself trying to run KSP on an older Win XP 32-bit rig. cmd.exe did not receive the /affinity switch until Vista, IIRC.
I realize OP is over a year old, however it is still currently an issue for some users. The solution is to use psexec.exe from Sysinternals in lieu of cmd.exe, which can be found here:
http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx
Microsoft's Sysinternal's psexec's -a flag can set processor affinity on Windows XP:
Usage: psexec [\\computer[,computer2[,...] | #file][-u user [-p psswd]][-n s][-l][-s|-e][-x][-i
[session]][-c [-f|-v]][-w directory][-d][-][-a n,n,...] cmd [arguments]
-a Separate processors on which the application can run with
commas where 1 is the lowest numbered CPU. For example,
to run the application on CPU 2 and CPU 4, enter:
"-a 2,4"
For example:
psexec -a 2 cmd /c "E:Games\KSP\KSP.exe"
Will run KSP on the 2nd core. (Core 1 in Task Manager)
Just correct the path for your system and put that in a .bat or the Target field of a shortcut.
And as an aside, you need to extract the PsTools (or simply PsExec.exe) either into C:\Windows or another folder that in the system path, or put it in your KSP root.

Answer 2

first be aware, you have to provide Administrator right to your program, either by right clic, and sart as admin, or by creating a task.
So, after you started your cmd with those admin right, you can start your program this way:
<code>`start /AFFINITY 1 /B notepad.exe`</code>
Using procexp, and right click + set affinity on the notepad process, you will see that it use only processor 0.
Doing:
<code>`start /AFFINITY 1 /B notepad.exe`</code>
And you'll see it running on processor 2.
Then if you want your process running on half of the core ?
Do this:
<code>`start /AFFINITY AA /B notepad.exe`</code>
On a octo core, it will run on processor 1, 3, 5, 7
/AA is for half of the cores, the odd, (1, 3, 5, 7)
/A is for quart of the cores, odd , (1, 3)
/F is for the first half, (0, 1, 2, 3)
/FF is for all, ( 0, 1, 2, 3, 4, 5, 6, 7)
Regards.