Which command writes the number of ERROR lines in system.log to task1_output.txt?
ERROR
system.log
task1_output.txt
grep -c 'ERROR' system.log > task1_output.txt
grep 'ERROR' system.log > task1_output.txt
grep -vc 'ERROR' system.log > task1_output.txt
grep -c task1_output.txt > system.log