* src/grpconv.c: Fail if not called correctly.

* src/grpconv.c: At the end of main, the passwd and shadow files
	are locked. No need to check before unlocking. No need to set the
	lock as false neither since there cannot be anymore failures.

src/grpconv.c

@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 1996 - 2000, Marek Michałkiewicz
  * Copyright (c) 2002 - 2006, Tomasz Kłoczko
+ * Copyright (c) 2011       , Nicolas François
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -91,6 +92,7 @@ int main (int argc, char **argv)
 
 	if (1 != argc) {
 		(void) fputs (_("Usage: grpconv\n"), stderr);
+		fail_exit (2);
 	}
 	Prog = Basename (argv[0]);
 
@@ -209,13 +211,11 @@ int main (int argc, char **argv)
 		SYSLOG ((LOG_ERR, "failed to unlock %s", sgr_dbname ()));
 		/* continue */
 	}
-	sgr_locked = false;
 	if (gr_unlock () == 0) {
 		fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, gr_dbname ());
 		SYSLOG ((LOG_ERR, "failed to unlock %s", gr_dbname ()));
 		/* continue */
 	}
-	gr_locked = false;
 
 	nscd_flush_cache ("group");