yistep.sh

#!/usr/bin/env bash

# Usage:
# ./yistep.sh [filename.yo]

# IMPORTANT!!
# In order to work properly, this script needs to be in the same directory
#  as your yis executable

# ---

# Run ./yis command with the first argument this script was run with ($1)
# Pipe that output to the head command, which deletes all but the first line
#   At this point, we are expecting the value to be "Stopped in XX steps ..."
# Pipe that output to awk, which selects the 3rd space-separated word of the line
# Store that output in the variable Max
Max=`./yis $1 | head -n 1 | awk -F ' ' '{ print $3 }'`
# $Max now stores the total number of steps required to run program to completion

# Use the GNU seq command to generate a sequence of numbers from 1 to $Max
# Make sure your computer has this command available by running "which seq" at the terminal
for i in $(seq "$Max");
do
    # Run ./yis with the original first argument of this script and the current value of $i
    ./yis $1 $i

    # Read a single character (-n1) from the user, and store it in the value $key
    read -n1 -r -p "Press any key to continue, or q to quit" key

    # Print a newline, since we might not have gotten one from the user just now
    printf '\n'

    # Quit if key pressed was 'q'
    if [ "$key" = "q" ]; then
        exit
    fi
done