[SCRIPT] Batch rename .gre.srt subtitle files to .ell.srt

What it does

This script recursively scans your Media library and renames subtitle files from the deprecated gre ISO 639-2 language code to the correct ell code for Modern Greek. Most modern media players and tools (Jellyfin, Plex, Kodi, etc.) now expect ell and may not recognise gre.

Example:

Movie.2020.gre.srt  →  Movie.2020.ell.srt

The script is designed to run safely on an Unraid server via the User Scripts plugin, with low I/O and CPU priority so it does not disturb normal operations.

*Feel free to adapt for other language code migrations (e.g. heb→iw, iw→he, etc.)

Requirements

• Unraid with the User Scripts plugin installed (Community Applications)

• Media stored under a consistent path (e.g. /mnt/user/Media/ or /mnt/user0/Media/)

Setup

1. Open Settings → User Scripts → Add New Script

2. Paste the full script into the editor

3. Edit the variables in the USER CONFIGURATION section at the top (see below)

4. Save and optionally set a schedule (e.g. monthly)

5. Run once with --dry-run first to verify what would be renamed

⚙️ User Configuration — Variables to customise

These are the only variables you should need to change. Everything else can be left as-is.

ROOTS — Your media paths

ROOTS=(
  "$BASE/Media/Movies"
  "$BASE/Media/TV Shows"
)

Change these to match your actual folder names. Add or remove lines as needed.

# Examples:
ROOTS=(
  "$BASE/Media/Films"
  "$BASE/Media/Series"
  "$BASE/Media/Documentaries"
)

$BASE is automatically set to /mnt/user or /mnt/user0 depending on your array layout — you typically don't need to change it. If your media is on a specific share or disk, you can override it manually:

BASE="/mnt/user"

LOG — Log file location

LOG="/mnt/user/appdata/srt_rename_gre_to_ell.log"

Change this if you prefer logs in a different location, e.g. inside a dedicated appdata subfolder.

LOG_MAX_LINES — Log rotation size

LOG_MAX_LINES=5000

The log file is trimmed to this many lines at the start of each run. Increase if you have a very large library and want more history, or decrease to keep things lean.

HEARTBEAT_SECS — Progress logging interval

HEARTBEAT_SECS=60

How often (in seconds) a progress line is written to the log while scanning. Useful for monitoring long runs. Set to 300 for less noise, or 15 for very frequent updates.

🚀 Run flags (optional)

You can pass these as Script Arguments in the User Scripts UI, or append them to the script call:

Recommended first run: Set Script Arguments to --dry-run and check the log at the path defined in LOG.

📋 What gets logged

Each run produces entries like:

[2025-03-08 14:00:01] ---- RUN START ----
[2025-03-08 14:00:01] Mode: FULL=1 | DRY_RUN=0 | FORCE=0 | Wake=1 | Heartbeat=60s
[2025-03-08 14:01:03] Renamed: /mnt/user/Media/Movies/Foo (2020)/Foo.gre.srt -> Foo.ell.srt
[2025-03-08 14:02:00] HEARTBEAT | elapsed=00:02:00 | found=145 renamed=12 skipped=3 errors=0
[2025-03-08 14:05:22] === DONE ===
[2025-03-08 14:05:22] TOTAL: Found=892 | Renamed=47 | Skipped=5 | Errors=0 | Duration=00:05:21

📝 Full Script

#!/bin/bash
set -euo pipefail
IFS=$'\n\t'

renice -n 15 -p $$ >/dev/null 2>&1 || true
ionice -c2 -n7 -p $$ >/dev/null 2>&1 || true

echo "=== STARTING SRT RENAME: .gre.srt -> .ell.srt ==="

# ============================================================
# USER CONFIGURATION — edit these to match your setup
# ============================================================

BASE="/mnt/user"
[[ -d "/mnt/user0/Media" ]] && BASE="/mnt/user0"

ROOTS=(
  "$BASE/Media/Movies"
  "$BASE/Media/TV Shows"
)

LOG="/mnt/user/appdata/srt_rename_gre_to_ell.log"
STATE="/mnt/user/appdata/srt_rename_gre_to_ell.last_run"
SUCCESS_MARK="/mnt/user/appdata/srt_rename_gre_to_ell.last_success"

LOG_MAX_LINES=5000
HEARTBEAT_SECS=60

# ============================================================
# END OF USER CONFIGURATION
# ============================================================

DRY_RUN=0
FORCE=0
FULL=1
WAKE_DISKS=1

while [[ $# -gt 0 ]]; do
  arg="${1//$'\r'/}"
  case "$arg" in
    "") shift ;;
    --dry-run) DRY_RUN=1; shift ;;
    --force)   FORCE=1; shift ;;
    --full)    FULL=1; shift ;;
    --inc)     FULL=0; shift ;;
    --wake)    WAKE_DISKS=1; shift ;;
    *) echo "Unknown option: [$(printf '%q' "$arg")]"; exit 1 ;;
  esac
done

mkdir -p "$(dirname "$LOG")"

if [[ -f "$LOG" ]]; then
  tmp_log="$(mktemp)"
  tail -n "$LOG_MAX_LINES" "$LOG" > "$tmp_log" && mv "$tmp_log" "$LOG"
fi

fmt_secs() {
  local s="$1"
  printf "%02d:%02d:%02d" $((s/3600)) $(((s%3600)/60)) $((s%60))
}

log() {
  local msg="$1"
  local ts
  ts="$(date '+%F %T')"
  echo "[$ts] $msg" | tee -a "$LOG"
  logger -t srt-rename "$msg" 2>/dev/null || true
}

missing=0
log "Using BASE: $BASE"
for r in "${ROOTS[@]}"; do
  if [[ ! -d "$r" ]]; then
    log "ERROR: root not found: $r"
    missing=1
  else
    log "OK: root exists: $r"
  fi
done
if [[ $missing -eq 1 ]]; then
  log "ABORT: Fix ROOTS and rerun."
  exit 1
fi

START_TS="$(date +%s)"
CURRENT_ROOT="(none)"
LAST_FILE="(none)"
LAST_BEAT_TS="$START_TS"

found=0 renamed=0 skipped=0 errors=0

beat() {
  local now elapsed
  now="$(date +%s)"
  elapsed=$((now - START_TS))
  log "HEARTBEAT | elapsed=$(fmt_secs "$elapsed") | root=\"$CURRENT_ROOT\" | found=$found renamed=$renamed skipped=$skipped errors=$errors | last=\"$LAST_FILE\""
  LAST_BEAT_TS="$now"
}

wake_all_disks() {
  log "Waking ALL array disks (/mnt/disk*) ..."
  shopt -s nullglob
  for d in /mnt/disk*; do
    [[ -d "$d" ]] || continue
    ls -1 "$d" >/dev/null 2>&1 || true
  done
  shopt -u nullglob
  log "Disk wake pass done."
}

process_one() {
  local file="$1"
  found=$(( found + 1 ))
  LAST_FILE="$file"

  local new_file
  new_file="$(printf '%s' "$file" | sed -E 's/\.gre\.srt$/.ell.srt/')"

  if [[ "$new_file" == "$file" ]]; then
    skipped=$(( skipped + 1 ))
    return
  fi

  if [[ -e "$new_file" && $FORCE -eq 0 ]]; then
    skipped=$(( skipped + 1 ))
    log "SKIP (target exists): $file -> $new_file"
    return
  fi

  if [[ $DRY_RUN -eq 1 ]]; then
    renamed=$(( renamed + 1 ))
    log "[DRY-RUN] Would rename: $file -> $new_file"
    return
  fi

  if mv -- "$file" "$new_file"; then
    renamed=$(( renamed + 1 ))
    log "Renamed: $file -> $new_file"
  else
    errors=$(( errors + 1 ))
    log "ERROR renaming: $file"
  fi
}

log "---- RUN START ----"
log "Roots: ${ROOTS[*]}"
log "Mode: FULL=$FULL | DRY_RUN=$DRY_RUN | FORCE=$FORCE | Wake=$WAKE_DISKS | Heartbeat=${HEARTBEAT_SECS}s"

if [[ $WAKE_DISKS -eq 1 ]]; then
  wake_all_disks
fi

if [[ $FULL -eq 0 ]]; then
  if [[ -f "$STATE" ]]; then
    log "Incremental since: $(date -r "$STATE")"
  else
    log "Incremental since: (none) -> first run will behave like full for matches"
  fi
else
  log "FULL scan mode"
fi

beat

for root in "${ROOTS[@]}"; do
  CURRENT_ROOT="$root"
  log "Scanning: $root"

  if [[ $FULL -eq 0 && -f "$STATE" ]]; then
    while IFS= read -r -d '' file; do
      now="$(date +%s)"
      if (( now - LAST_BEAT_TS >= HEARTBEAT_SECS )); then
        beat
      fi
      process_one "$file"
    done < <(find "$root" \( -type d -name ".Recycle.Bin" -prune \) -o \
      \( -type f -iname "*.gre.srt" -newer "$STATE" -print0 \))
  else
    while IFS= read -r -d '' file; do
      now="$(date +%s)"
      if (( now - LAST_BEAT_TS >= HEARTBEAT_SECS )); then
        beat
      fi
      process_one "$file"
    done < <(find "$root" \( -type d -name ".Recycle.Bin" -prune \) -o \
      \( -type f -iname "*.gre.srt" -print0 \))
  fi

  beat
  log "Finished root: $root"
done

END_TS="$(date +%s)"
TOTAL_SECS=$((END_TS - START_TS))

log "=== DONE ==="
log "TOTAL: Found=$found | Renamed=$renamed | Skipped=$skipped | Errors=$errors | Duration=$(fmt_secs "$TOTAL_SECS")"

if [[ $DRY_RUN -eq 0 && $errors -eq 0 ]]; then
  touch "$STATE"
  touch "$SUCCESS_MARK"
  log "State updated: $STATE"
  log "Success marker updated: $SUCCESS_MARK"
else
  log "State NOT updated (dry-run or errors present)"
fi

exit 0

Notes

• The script skips .Recycle.Bin folders automatically

• If a .ell.srt file already exists at the destination, the original is skipped (use --force to override)

• State files are only updated if the run completes with zero errors

• Logs go to both the file and Unraid's syslog (logger)

Tested on Unraid 7.2.+

📁 GitHub Repository: Link

Edited March 8Mar 8 by Lazaros Chalkidis