PATH is erased/replaced

[jan007]

Hi,
I've made a commandline utility (.exe) that depends on a couple of dll's.
After looking for some kind of packer that would allow me to let users download and use a single (working) exe (with the dll's included) it seems that is impossible.
So someone pointed me to NSIS, which is a great tool, although I don't actually need to install software.

Crucial in my setup is that users don't have to add the directory with the exe to their environmental PATH variable. NSIS does a great job with this but in my case it erased my entire PATH even though I used A(ppend).
Gladly enough I read a lot of related posts before I tried, so I made a backup of my PATH.
But I can't seem to find a solution to this problem. My PATH contains 1081 characters and slimming it down does solve the problem. But I can't ask my users to do that or otherwise I could just as well offer a zip and make them add the dir to their PATH themselves.

1)Is there a 'real' solution to this problem?
2)Can I otherwise somehow count the characters of their PATH variable and show a warning that their PATH will not be updated and that they will (still) have to add it themselves manually and show/link to a manual of how to do this?
3)The directory which should added to the PATH variable is now hardcoded in my nsi script, but when people choose to 'install' in another directory this won't be correct. How can I retrieve what 'custom' directory they choose and use that dir to append to their PATH?
4)As I said before: I'm not actually installing software, it's more like saving into a dir and setting up the PATH. So, can I leave out all the registry stuff from the example.nsi or can this be usefull for other things such as an uninstaller which in my case would be just to remove the dir+contents and the PATH var?

I'm using NSIS 2.45 and Windows XP.

Thanks in advance!

Although the provided examples seem quite easy to change to reflect my setup I'm still posting it to make sure it does not contain unwanted, unneeded or even dangerous stuff.

code:
!include EnvVarUpdate.nsh

Name "MyApp"

OutFile "MyApp_installer.exe"

InstallDir $PROGRAMFILES\MyApp

InstallDirRegKey HKLM "Software\MyApp" "Install_Dir"

RequestExecutionLevel admin



Page components

Page directory

Page instfiles



UninstPage uninstConfirm

UninstPage instfiles



Section "MyApp (required)"

  SectionIn RO

  

  SetOutPath $INSTDIR

  

  File "MyApp.exe"

  File "gc.dll"

  File "neko.dll"

  File "regexp.ndll"

  File "std.ndll"

  File "zlib.ndll"	

  File "LICENSE"	

  File "neko_source_download.txt"

  File "howto.txt"	

	

  WriteRegStr HKLM SOFTWARE\MyApp "Install_Dir" "$INSTDIR"



  WriteRegStr HKLM "Software\Microsoft\Windows\CurrentVersion\Uninstall\MyApp" "DisplayName" "MyApp"

  WriteRegStr HKLM "Software\Microsoft\Windows\CurrentVersion\Uninstall\MyApp" "UninstallString" '"$INSTDIR\uninstall.exe"'

  WriteRegDWORD HKLM "Software\Microsoft\Windows\CurrentVersion\Uninstall\MyApp" "NoModify" 1

  WriteRegDWORD HKLM "Software\Microsoft\Windows\CurrentVersion\Uninstall\MyApp" "NoRepair" 1

  WriteUninstaller "uninstall.exe"

  ${EnvVarUpdate} $0 "PATH" "A" "HKLM" "C:\Program Files\MyApp"

SectionEnd



Section "Start Menu Shortcuts (uninstaller)"

  CreateDirectory "$SMPROGRAMS\MyApp"

  CreateShortCut "$SMPROGRAMS\MyApp\Uninstall.lnk" "$INSTDIR\uninstall.exe" "" "$INSTDIR\uninstall.exe" 0

  CreateShortCut "$SMPROGRAMS\MyApp\howto.lnk" "$INSTDIR\howto.txt" "" "$INSTDIR\howto.txt" 0

SectionEnd



Section "Uninstall"

  DeleteRegKey HKLM "Software\Microsoft\Windows\CurrentVersion\Uninstall\MyApp"

  DeleteRegKey HKLM SOFTWARE\MyApp



  Delete $INSTDIR\MyApp.exe

  Delete $INSTDIR\uninstall.exe

  Delete $INSTDIR\gc.dll

  Delete $INSTDIR\neko.dll

  Delete $INSTDIR\regexp.ndll

  Delete $INSTDIR\std.ndll

  Delete $INSTDIR\zlib.ndll

  Delete $INSTDIR\LICENSE

  Delete $INSTDIR\neko_source_download.txt

  Delete $INSTDIR\howto.txt



  Delete "$SMPROGRAMS\MyApp\*.*"



  RMDir "$SMPROGRAMS\MyApp"

  RMDir "$INSTDIR"

	

	${un.EnvVarUpdate} $0 "PATH" "R" "HKLM" "C:\Program Files\MyApp"

SectionEnd

Cheers,

Jan