# tcsim_filter dev=xxx works --------------------------------------------------
tcsim | tcsim_filter dev=foo tos
#include "packet.def"

dev foo
dev bar

send foo IP_PCK($ip_tos=23)
send bar IP_PCK($ip_tos=42)
EOF
0.000000 E:17 20 0x00000000
# tcsim_filter does not output packet ID --------------------------------------
tcsim | tcsim_filter
dev eth0
send 0
EOF
0.000000 E 1 0x00000000
# fw filter does not allow element number 0 -----------------------------------
tcsim 2>&1
dev eth0 {
    prio {
	fw {
	    class on element(0);
	}
    }
}
EOF
ERROR
<stdin>:4: fw element ID must be non-zero
