made snprintf() return the number of characters written on success, as it advertises to do

SVN revision: 12063

legacy/embryo/src/lib/embryo_str.c

@@ -383,7 +383,7 @@ _embryo_str_snprintf(Embryo_Program *ep, Embryo_Cell *params)
    s2[o] = 0;
    
    STRSET(ep, params[1], s2);
-   return 0;
+   return strlen(s2);
 }
 
 static Embryo_Cell