diff --git a/tests/various/clk2fflogic_effects.sh b/tests/various/clk2fflogic_effects.sh
index b51424d1b..f44afc1dd 100755
--- a/tests/various/clk2fflogic_effects.sh
+++ b/tests/various/clk2fflogic_effects.sh
@@ -4,7 +4,7 @@ set -ex
 ../../yosys -p "
 read_verilog -formal -DFAST clk2fflogic_effects.sv
 hierarchy -top top; proc;;
-tee -o clk2fflogic_effects.sim.log sim -fst /tmp/sim.fst -q -n 16
+tee -o clk2fflogic_effects.sim.log sim -fst clk2fflogic_effects.sim.fst -q -n 16
 "
 
 ../../yosys -p "
@@ -12,7 +12,7 @@ read_verilog -formal -DFAST clk2fflogic_effects.sv
 hierarchy -top top; proc;;
 clk2fflogic;;
 
-tee -o clk2fflogic_effects.clk2fflogic.log sim -fst /tmp/sim.fst -q -n 16
+tee -o clk2fflogic_effects.clk2fflogic.log sim -fst clk2fflogic_effects.clk2fflogic.fst -q -n 16
 "
 
 iverilog -g2012 -o clk2fflogic_effects.iv.out clk2fflogic_effects.sv
@@ -20,8 +20,8 @@ iverilog -g2012 -o clk2fflogic_effects.iv.out clk2fflogic_effects.sv
 ./clk2fflogic_effects.iv.out > clk2fflogic_effects.iv.log
 
 sort clk2fflogic_effects.iv.log > clk2fflogic_effects.iv.sorted.log
-tail +3 clk2fflogic_effects.sim.log | sort > clk2fflogic_effects.sim.sorted.log
-tail +3 clk2fflogic_effects.clk2fflogic.log | sort > clk2fflogic_effects.clk2fflogic.sorted.log
+tail -n +3 clk2fflogic_effects.sim.log | sort > clk2fflogic_effects.sim.sorted.log
+tail -n +3 clk2fflogic_effects.clk2fflogic.log | sort > clk2fflogic_effects.clk2fflogic.sorted.log
 
 cmp clk2fflogic_effects.iv.sorted.log clk2fflogic_effects.sim.sorted.log
 cmp clk2fflogic_effects.iv.sorted.log clk2fflogic_effects.clk2fflogic.sorted.log