Dumb more/less command if the system doesn't give you one and you don't want to install

more

#!/bin/ash

# Default lines per page
LINES_PER_PAGE=${PAGER_LINES:-20}



# Function to display a page
display_page() {
    local start_line=$1
    local end_line=$2
    while [ $CURRENT_LINE -le $END_LINE ]; do
        if IFS= read -r aline ; then
           echo "$aline"
           CURRENT_LINE=$(( CURRENT_LINE + 1 ))
        else
            EOF=1
            break
        fi
    done

}

# Check if a file is provided
DONE=0
FN=stdin

while [ $DONE -eq 0 ] ; do
    if [ ! -z "$1" ]; then
        exec 0< "$1"
        FN="$1"
        shift
    fi
    CURRENT_LINE=0
    EOF=0
    if [ -z "$1" ]; then
        DONE=1     # done when this is over?
    fi
    while [ $EOF == 0 ] ; do
       END_LINE=$(( CURRENT_LINE + LINES_PER_PAGE - 1 ))
       clear # Clear screen for a cleaner page display
       display_page "$CURRENT_LINE" "$END_LINE"

       if [ $EOF == 0 -o $DONE == 0 ]; then
           echo -e "\n$FN -- Press Enter for next page, 'q' to quit 'n' for next file --"
           read -r -n 1 USER_INPUT </dev/tty
           if [[ "$USER_INPUT" == "n" || "$USER_INPUT" == "N" ]]; then
               EOF=1
               break;
           fi
           if [[ "$USER_INPUT" == "q" || "$USER_INPUT" == "Q" ]]; then
               EOF=1
               DONE=1   # bail
               break
           fi
         fi
         CURRENT_LINE=$((END_LINE + 1))
    done
    if [ ! -z "$1" ]; then
        true
    else
        break
    fi
done