AutoHotkey Community

[Samlii]

I am trying to do some things with the Environment, and so when I set up an enviroment variable (like comspec) that points to other env variables (comspec = %SystemRoot%\cmd.exe)

When I try to Run, %comspec% it fails saying it can't find the file (Its looking for %SystemRoot%\cmd.exe, literally)

Any way to tel the string to expand? Will StringRepl Replace the string when it transfers to the secondVariable?

Sam

[PenP]

Hi,

%SystemRoot%\cmd.exe is not the same as %COMSPEC%, try this:

[Chris]

(to add a little detail to the above reply)

The problem is that cmd.exe is in the system32 folder (at least on my system). Thus, the following works:

comspec = %SystemRoot%\system32\cmd.exe
run %comspec%

But are you sure you need to set the comspec variable? It is typically already defined, so you can omit the first line and just do:
Run %comspec%

[samlii]

I know its normally defined, and yes you are correct I missed the system32,

However that is not the problem.

What I am doing is resetting my Environment:

#+t::
MsgBox, 0, , "Comspec is %comspec%"
MsgBox, 0, , "SystemRoot is %SystemRoot%"
Run, %comspec% /k
return
#+r::
MsgBox, 0, , "Your environment settings are:"
Loop, HKEY_LOCAL_MACHINE, SYSTEM\CurrentControlSet\Control\Session Manager\Environment, 0, 0
{
RegRead, value
if ErrorLevel <> 0
value = *error*
EnvSet %a_LoopRegName%, ""
}
Loop, HKEY_LOCAL_MACHINE, SYSTEM\CurrentControlSet\Control\Session Manager\Environment, 0, 0
{
RegRead, value
if ErrorLevel <> 0
value = *error*
MsgBox, 0, , Setting %a_LoopRegName% to %value%
EnvSet %a_LoopRegName%, %value%
lm%a_LoopRegName% = %value%
}


The problem is when I try to run comspec again (which is defined as %SystemRoot%\system32\cmd.exe) it says it can't find the file specified.

%SystemRoot% is defined as c:\Winnt (on my win2k machine)

Could it be something in how they are being set? (ie escaping the %'s without my knowledge?)

[Chris]

A few things that might help:
1) When a script changes environment variables, the changes are not seen by other scripts and applications (except for processes created via Run/RunWait by a compiled script, I think). You would probably have to use System Properties -> Advanced -> Environment variables to make them take effect globally.

2) If a script variable of the same name as an environment variable is assigned a value, it will "hide" the environment variable from the script. In other word's, the script's own variable will take precedence.

3) If you open the script's main window via the tray icon, you can select View > Variables to find out what's in the script's variables (not the environment variables). Or you can add a MsgBox at a critical section in the script where you're experiencing a problem.

If the above doesn't help, perhaps you can post a specific short script that fails the produce the expected result... something I can run to try to analyze it.

[Samlii]

Chris,

Nothing is getting overwritten. The whole reason I am doing this is so that when I change the system Environment (through the System Properties), the script can pick up that change without having to exit the script (completely) and re start it

Here is a small Script that I think reflects the problem:

sysval = `%Bob`%
systest = %sysval%Test
Bob = Alice
MsgBox, 0, , %systest%
return

I think sysval is an accurate representation of what I get from the RegRead when the value has a %x% in it.

[Chris]

I understand now. The problem is that percent signs are evaluated only when physically present. You can't have percent signs inside a variable and have them evaluated later.

However, you can use any function that takes an input variable, such as StringTrimRight, to dynamically resolve the contents of a variable. For example:

sysval = Bob
Bob = Alice
StringTrimRight, systest, %sysval%, 0 ; This is the key line.
MsgBox, 0, , %systest%
return

But you might be able to avoid all the above by using EnvUpdate described at http://www.autohotkey.com/docs/commands/EnvUpdate.htm

[Samlii]

Chris,

First, thanks for taking the time with this, and thanks for creating the program, I don't want you to feel like I don't appreciate it.

Second, I started out trying to use Env Update, but it wouldn't retreive new values set from the Environment properties dialog. Maybe I am doing something wrong, does it work this way for you?

[Chris]

I tried the following script and it didn't work for me either:

msgbox %thing%
pause ; Here I added "thing" as a new environment var. in Sys Properties.
EnvUpdate
msgbox %thing%

Not only didn't it work, but a new cmd prompt I launched didn't see the change either. I think this aspect of the OS just isn't very reliable. Logging off and then on again might be the only sure way to update the variables.

Other than this, I don't know much about EnvUpdate other than what's documented in the help file. Internally, all it does is:

SendMessage(HWND_BROADCAST, WM_SETTINGCHANGE, 0, (LPARAM)"Environment")

You can try to google some of those keywords to see if there is more info.

[Guest]

Well thanks for trying Chris, according to MSDN the updates are sent to the to level windows, so either the system isn't sending the correct update message, or AHK isn't handling it correctly in the message loop. Maybe I'll look at the code later, if I find time DO you know if it compiles with MingW or only with VC?

Anyways I found a way around it:

#+r::
null = %SystemRoot%
null = %USERPROFILE%
Loop, HKEY_LOCAL_MACHINE, SYSTEM\CurrentControlSet\Control\Session Manager\Environment, 0, 0
{
RegRead, value
if ErrorLevel <> 0
value = *error*
EnvSet %a_LoopRegName%, ""
}
Loop, HKEY_CURRENT_USER, Environment, 0, 0
{
RegRead, value
if ErrorLevel <> 0
value = *error*
EnvSet %a_LoopRegName%, ""
}
Loop, HKEY_LOCAL_MACHINE, SYSTEM\CurrentControlSet\Control\Session Manager\Environment, 0, 0
{
RegRead, value
if ErrorLevel <> 0
value = *error*
EnvSet %a_LoopRegName%, %value%
StringLower, keyLower, a_LoopRegName
lm%keyLower% = %value%
}
Loop, HKEY_CURRENT_USER, Environment, 0, 0
{
RegRead, value
if ErrorLevel <> 0
value = *error*
StringLower, keyLower, a_LoopRegName

IfNotEqual, lm%keyLower%,
{
StringTrimRight, clipboard, lm%keyLower%, 0
EnvSet %a_LoopRegName%, %clipboard%;%value%
}
else
{
EnvSet %a_LoopRegName%, %value%
}
}
expandLeaveUnknown = off
Loop, HKEY_LOCAL_MACHINE, SYSTEM\CurrentControlSet\Control\Session Manager\Environment, 0, 0
{
RegRead, value
if ErrorLevel <> 0
continue
clipboard = %value%
GoSub ExpandInternal
EnvSet %a_LoopRegName%, %clipboard%
}
Loop, HKEY_CURRENT_USER, Environment, 0, 0
{
RegRead, value
if ErrorLevel <> 0
continue
clipboard = %value%
GoSub ExpandInternal
EnvSet %a_LoopRegName%, %clipboard%
}
EnvUpdate
return

ExpandInternal:
percPos = 1
Loop
{
oldpercPos = %percPos%

StringGetPos, startPercent, clipboard, `%, L%percPos%
If errorlevel <> 0
break

percPos++
StringGetPos, endPercent, clipboard, `%, L%percPos%
If errorlevel <> 0
break
percPos++

endPercent -= %startPercent% ; find amount of chars between start and end
endPercent -= 1 ; Take one away since we dont want the last percent
startPercent += 2 ; Because of the fact that start position is specified and getPos starts at zero we add two

StringMid, varName, clipboard, %startPercent%, %endPercent%
StringTrimLeft, varValue, %varName%, 0

IfEqual, varValue,
{
IfEqual, expandLeaveUnknown, on
Continue
}

MsgBox, 0, , Replacing %varname% with %varValue%
StringReplace, clipboard, clipboard, `%%varName%`%, %varValue%, All

percPos = %oldpercPos%

}
return

[Samlii]

One other thing,

The two nulls up at the top (null = %SystemRoot%) had to be done so that when the varValue was found for the replace it would find them, otherwise they came back as empty values, any ideas as to why?

Also is there a way to either 1) make real functions, or 2) give a Sub args, otherthan how I did it? (Without modifying the actual cpp source?)

[Chris]

[Samlii]

[Chris]

I see it now, thanks a lot. In tomorrow's release, the following change will appear:

Fixed InputVars that dynamically resolve to the names of environment variables. Sometimes the value was not being fetched from the environment [thanks Samlii]. Example:
EnvVar = SystemRoot
StringTrimLeft, OutputVar, %EnvVar%, 0