backfill.sh

#!/usr/bin/env bash
# modified as PLC doesnt process *.bin files
set -euo pipefail

BASE="/media/eri/6634-6631/FCDATA01/DATALOG/1-secLog"
START_DATE="20260401"

CHUNK_MB=16
RESERVE_MB=10000

TMPFILE="/home/eri/Desktop/out.csv"

# Create reusable file once
if [[ ! -f "$TMPFILE" ]]; then
    echo "Creating temp file $TMPFILE (${CHUNK_MB} MB)..."
    dd if=/dev/zero of="$TMPFILE" bs=1M count="$CHUNK_MB" status=progress
fi

current="$START_DATE"

while true; do
    current=$(date -d "${current} -1 day" +%Y%m%d)
    dir="$BASE/$current"
    mkdir -p "$dir"

    free_kb=$(df --output=avail "$BASE" | tail -n 1)
    free_mb=$((free_kb / 1024))

    usable_mb=$((free_mb - RESERVE_MB))
    if (( usable_mb <= 0 )); then
        echo "Stopping: not enough free space left."
        break
    fi

    outfile="$dir/file.csv"

    echo "Writing $outfile (${CHUNK_MB} MB)..."
    cp "$TMPFILE" "$outfile"
done

echo "Done."