the order is: write a makelineup program, e.g., mymakelineup this takes a single input "l" or "r" on its own line which represents the starting pitcher's throwing side and it reads the "batters" file and it outputs 9 numbers, in order, each on its own line, e.g. 13 14 9 4 1 5 6 2 15 make sure makelineup is executable (chmod a+x makelineup) and if . is not in your path, you say ./makelineup also, check that gawk is in the right place by saying "which gawk" to the shell and comparing the path to the first line of makelineup run sim4: sim4 -v prog=mymakelineup -v remake=0 -v output=1 -v iters=200 | less or just sim4 -v remake=0 sim4 -v remake=0 -v output=1 | less make sure sim4 is executable (chmod a+x sim4) and if . is not in your path, you say ./sim4 also, check that gawk is in the right place by saying "which gawk" to the shell and comparing the path to the first line of sim4 ps, bug was fixed for walking a run in "0 runs score"