Get tmp dir from environment (also check TMP and TEMP)

Follow new JAliEn feature to allow storing token certs in a custom tmp location

TJAlien.cxx

@@ -43,6 +43,20 @@ TJAlien::TJAlien (const char* gridUrl, const char* uId, const char* passwd,
     fGrid = "alien";
     gGrid = this;
 
+    if (getenv("HOME") != NULL)
+        homedir = getenv("HOME");
+    else
+        homedir = "~";
+
+    if (getenv("TMPDIR") != NULL)
+        tmpdir = getenv("TMPDIR");
+    else if (getenv("TMP") != NULL)
+        tmpdir = getenv("TMP");
+    else if (getenv("TEMP") != NULL)
+        tmpdir = getenv("TEMP");
+    else
+        tmpdir = P_tmpdir;
+
     CreateConnection();
 }
 
@@ -69,16 +83,6 @@ void TJAlien::CreateConnection()
         readBuffer = "";
 
         // Load certificate
-        if (getenv("HOME") == NULL)
-            homedir = "~";
-        else
-            homedir = getenv("HOME");
-
-        if (getenv("TMPDIR") == NULL)
-            tmpdir = P_tmpdir;
-        else
-            tmpdir = getenv("TMPDIR");
-
         std::stringstream tokencert_s, tokenkey_s;
 
         tokencert_s << tmpdir << "/tokencert_" << getuid() << ".pem";