_4ti2: patch in absolute patch to which

pkgs/by-name/_4/_4ti2/package.nix

@@ -5,6 +5,7 @@
   autoreconfHook,
   glpk,
   gmp,
+  which,
 }:
 
 stdenv.mkDerivation (finalAttrs: {
@@ -18,6 +19,12 @@ stdenv.mkDerivation (finalAttrs: {
     hash = "sha256-bFvq90hLLGty7p6NLxOARVvKdizg3bp2NkP9nZpVFzQ=";
   };
 
+  postPatch = ''
+    substituteInPlace src/{groebner/script.template.in,zsolve/{graver,hilbert}.template} \
+      --replace-fail 'SCRIPT=$(realpath $(which "$0"))' \
+                     'SCRIPT=$(realpath $(${lib.getExe which} "$0"))'
+  '';
+
   nativeBuildInputs = [
     autoreconfHook
   ];