Index: main/file.c
===================================================================
--- main/file.c	(revision 300622)
+++ main/file.c	(working copy)
@@ -310,11 +310,9 @@
 		ast_translator_free_path(f->trans);
 
 	if (f->realfilename && f->filename) {
-			size = strlen(f->filename) + strlen(f->realfilename) + 15;
-			cmd = alloca(size);
-			memset(cmd,0,size);
-			snprintf(cmd, size, "/bin/mv -f \"%s\" \"%s\"", f->filename, f->realfilename);
-			ast_safe_system(cmd);
+		if (ast_safe_fork(0) == 0) {
+			execl("/bin/mv", "mv", "-f", f->filename, f->realfilename, SENTINEL);
+		}
 	}
 
 	if (f->filename)