diff --git a/configure.ac b/configure.ac
index cc2a577..2fa04ef 100644
--- a/configure.ac
+++ b/configure.ac
@@ -81,15 +81,26 @@ then
   AC_DEFINE([LOG], [1], [Enable log])
 fi
 
-# Conf support (default:yes)
-AC_ARG_ENABLE([conf],AS_HELP_STRING([--disable-conf],[Disable use of config files and environment variables]),[enable_conf=$enableval],[enable_conf="yes"])
-AC_MSG_CHECKING(for conf flag)
-AC_MSG_RESULT($enable_conf)
-AM_CONDITIONAL([WITH_CONF], [test "$enable_conf" != "no"])
+# Conffiles support (default:yes)
+AC_ARG_ENABLE([conffiles],AS_HELP_STRING([--disable-conffiles],[Disable use of config files]),[enable_conffiles=$enableval],[enable_conffiles="yes"])
+AC_MSG_CHECKING(for conffiles flag)
+AC_MSG_RESULT($enable_conffiles)
+AM_CONDITIONAL([WITH_CONFFILES], [test "$enable_conffiles" != "no"])
  
-if test x"$enable_conf" = "xyes"
+if test x"$enable_conffiles" = "xyes"
 then
-  AC_DEFINE([CONF], [1], [Enable conf])
+  AC_DEFINE([CONFFILES], [1], [Enable conffiles])
+fi
+
+# Envvars support (default:yes)
+AC_ARG_ENABLE([envvars],AS_HELP_STRING([--disable-envvars],[Disable use of environment variables]),[enable_envvars=$enableval],[enable_envvars="yes"])
+AC_MSG_CHECKING(for envvars flag)
+AC_MSG_RESULT($enable_envvars)
+AM_CONDITIONAL([WITH_ENVVARS], [test "$enable_envvars" != "no"])
+ 
+if test x"$enable_envvars" = "xyes"
+then
+  AC_DEFINE([ENVVARS], [1], [Enable envvars])
 fi
 
 # Debug support (default:no)
diff --git a/libnfc/conf.c b/libnfc/conf.c
index 2fa744f..87aec26 100644
--- a/libnfc/conf.c
+++ b/libnfc/conf.c
@@ -21,7 +21,7 @@
 #  include "config.h"
 #endif // HAVE_CONFIG_H
 
-#ifdef CONF
+#ifdef CONFFILES
 #include <stdio.h>
 #include <stdlib.h>
 #include <dirent.h>
@@ -190,5 +190,5 @@ conf_load(nfc_context *context)
   conf_devices_load(LIBNFC_DEVICECONFDIR, context);
 }
 
-#endif // CONF
+#endif // CONFFILES
 
diff --git a/libnfc/log-printf.c b/libnfc/log-printf.c
index d0405d5..e8ef238 100644
--- a/libnfc/log-printf.c
+++ b/libnfc/log-printf.c
@@ -34,7 +34,7 @@
 void
 log_init(const nfc_context *context)
 {
-#ifdef CONF
+#ifdef ENVVARS
   char str[32];
   sprintf(str, "%"PRIu32, context->log_level);
   setenv("LIBNFC_LOG_LEVEL", str, 1);
@@ -52,7 +52,7 @@ void
 log_put(const uint8_t group, const char *category, const uint8_t priority, const char *format, ...)
 {
   char *env_log_level = NULL;
-#ifdef CONF
+#ifdef ENVVARS
   env_log_level = getenv("LIBNFC_LOG_LEVEL");
 #endif
   uint32_t log_level;
diff --git a/libnfc/nfc-internal.c b/libnfc/nfc-internal.c
index 8afa5fb..5a40325 100644
--- a/libnfc/nfc-internal.c
+++ b/libnfc/nfc-internal.c
@@ -29,7 +29,7 @@
 #include "config.h"
 #endif
 
-#ifdef CONF
+#ifdef CONFFILES
 #include "conf.h"
 #endif
 
@@ -88,7 +88,7 @@ nfc_context_new(void)
   }
   res->user_defined_device_count = 0;
 
-#ifdef CONF
+#ifdef ENVVARS
   // Load user defined device from environment variable at first
   char *envvar = getenv("LIBNFC_DEFAULT_DEVICE");
   if (envvar) {
@@ -97,9 +97,14 @@ nfc_context_new(void)
     res->user_defined_device_count++;
   }
 
+#endif // ENVVARS
+
+#ifdef CONFFILES
   // Load options from configuration file (ie. /etc/nfc/libnfc.conf)
   conf_load(res);
+#endif // CONFFILES
 
+#ifdef ENVVARS
   // Environment variables
   // Load "intrusive scan" option
   envvar = getenv("LIBNFC_INTRUSIVE_SCAN");
@@ -110,7 +115,7 @@ nfc_context_new(void)
   if (envvar) {
     res->log_level = atoi(envvar);
   }
-#endif // CONF
+#endif // ENVVARS
 
   // Initialize log before use it...
   log_init(res);
diff --git a/libnfc/nfc.c b/libnfc/nfc.c
index a9fe746..b3ce252 100644
--- a/libnfc/nfc.c
+++ b/libnfc/nfc.c
@@ -294,13 +294,15 @@ nfc_list_devices(nfc_context *context, nfc_connstring connstrings[], const size_
 {
   size_t device_found = 0;
 
-#ifdef CONF
+#ifdef CONFFILES
   // Load manually configured devices (from config file and env variables)
   // TODO From env var...
   for (uint32_t i = 0; i < context->user_defined_device_count; i++) {
     if (context->user_defined_devices[i].optional) {
       // let's make sure the device exists
       nfc_device *pnd = NULL;
+
+#ifdef ENVVARS
       char *env_log_level = getenv("LIBNFC_LOG_LEVEL");
       char *old_env_log_level = NULL;
       // do it silently
@@ -312,13 +314,19 @@ nfc_list_devices(nfc_context *context, nfc_connstring connstrings[], const size_
         strcpy(old_env_log_level, env_log_level);
       }
       setenv("LIBNFC_LOG_LEVEL", "0", 1);
+#endif // ENVVARS
+
       pnd = nfc_open(context, context->user_defined_devices[i].connstring);
+
+#ifdef ENVVARS
       if (old_env_log_level) {
         setenv("LIBNFC_LOG_LEVEL", old_env_log_level, 1);
         free(old_env_log_level);
       } else {
         unsetenv("LIBNFC_LOG_LEVEL");
       }
+#endif // ENVVARS
+
       if (pnd) {
         nfc_close(pnd);
         log_put(LOG_GROUP, LOG_CATEGORY, NFC_LOG_PRIORITY_DEBUG, "User device %s found", context->user_defined_devices[i].name);
@@ -335,7 +343,7 @@ nfc_list_devices(nfc_context *context, nfc_connstring connstrings[], const size_
         return device_found;
     }
   }
-#endif // CONF
+#endif // CONFFILES
 
   // Device auto-detection
   if (context->allow_autoscan) {