chjfth
20th December 2007 01:45 UTC

How to check env-var on compile time
HELP. I'd like to check whether an environment variable is defined when compiling an nsi file(because which files to pack relies on that env-var).

To check env-var UTBS, I tried :

!if "$%UTBS%" == ""
  !echo "Env-var UTBS is not defined. I cannot continue."
!else
  !echo "Env-var UTBS is defined to $%UTBS%"
!endif

If UTBS is defined, NSIS compiler outputs what we expect, i.e. %UTBS% is replaced with what UTBS's value is.

But if UTBS is not defined, it outputs

Processing script file: "checkenv.nsi"
Env-var UTBS is defined to $%UTBS% (checkenv.nsi:5)

That is not I'm expecting.

What can I do? (using NSIS v2.31)

{_trueparuex^}
20th December 2007 12:40 UTC

Edit: My workaround... It didn't work. :)

Edit 2:
Okay this one should work...

!define S $

!if "$%UTBS%" == "${S}%UTBS%"
  !echo "Env-var UTBS is not defined. I cannot continue."
!else
  !echo "Env-var UTBS is defined to $%UTBS%"
!endif

In compile time $$ constants doesn't work in front of the environment variable. So using !if "$%UTBS%" == "$$%UTBS%" didn't work.

chjfth
21st December 2007 11:25 UTC

Thank you very much. Your trick really works.