Remove unimplemented CLI options

2026-08-11 20:59:06 +02:00
parent 09fca8d931
commit d146e1bb7c
11 changed files with 138 additions and 385 deletions
@@ -40,12 +40,10 @@ A high-performance file synchronization system with SSH and TCP transport, TLS e
 - Optional progress display with throughput
 - Bandwidth limiting via token-bucket algorithm
 - Configurable I/O and connection timeouts (`--timeout`, `--contimeout`)
- Quiet mode (`-q`/`--quiet`) suppresses all non-error output
 - Backup overwritten files (`--backup`) with optional directory (`--backup-dir`)
 - Transfer statistics summary (`--stats`)
 - Maximum directory depth control (`--max-depth`)
 - Log file output (`--log-file`)
- Configurable multithreaded queue size (`--queue-size`)
 - Exclude patterns from file (`--exclude-from`)

 ### Server
@@ -114,8 +112,6 @@ Abort (`STATUS_ABORT`) may be sent at any point. On receipt the server cleans up
 | `-n, --dry-run` | Scan and print what would be transferred |
 | `-p <port>` | SSH port (default: 22) |
 | `-v, --verbose` | Enable debug logging |
-| `-q, --quiet` | Suppress all non-error output |
-| `--silent` | Alias for `--quiet` |
 | `--progress` | Show real-time transfer speed |
 | `--delete` | Delete files on receiver not present in source |
 | `--exclude <pattern>` | Exclude files matching glob pattern (repeatable) |
@@ -133,7 +129,6 @@ Abort (`STATUS_ABORT`) may be sent at any point. On receipt the server cleans up
 | `--stats` | Print transfer statistics at end (bytes, files, timing) |
 | `--max-depth <n>` | Maximum directory depth to recurse (0 = unlimited, default: 0) |
 | `--log-file <path>` | Write log messages to file instead of stderr |
-| `--queue-size <n>` | Queue capacity for multithreaded mode (default: 100) |
 | `--source-dir <path>` | Source directory (overrides `FASTSYNC_SOURCE_DIR`) |
 | `--dest-dir <path>` | Server destination directory (overrides `FASTSYNC_DEST_DIR`) |
 | `--save-to-disk` | Write received files to disk |
@@ -177,7 +172,7 @@ Abort (`STATUS_ABORT`) may be sent at any point. On receipt the server cleans up
 1. **Chunk** — collection of files (~10 MB total by default)
 2. **File** — path, content (`Data`), optional `FileMetadata` pointer
 3. **FileMetadata** — `mode`, `uid`, `gid`, `mtime_sec`, `mtime_nsec`
-4. **Config** — runtime parameters (transported over wire, TLS settings excluded). Includes `timeout`, `contimeout`, `quiet`, `backup`, `backup_dir`, `stats`, `max_depth`, `log_file`, `queue_size`.
+4. **Config** — runtime parameters (transported over wire, TLS settings excluded). Includes `timeout`, `contimeout`, `backup`, `backup_dir`, `stats`, and `max_depth`.
 5. **Queue** — thread-safe bounded queue with condition variables
 6. **DirectoryScanner** — recursive BFS traversal with exclude and include pattern support, max-depth enforcement

@@ -294,8 +289,8 @@ Place the `fastsync-server` binary in the remote `$PATH`. The client runs `ssh u
 # Bandwidth limit to 1 MB/s
 ./build/client --bwlimit 1024 /src user@host:/dst

-# With timeouts, quiet mode, and stats
-./build/client --timeout 60 --contimeout 15 --quiet --stats /src user@host:/dst
+# With timeouts and stats
+./build/client --timeout 60 --contimeout 15 --stats /src user@host:/dst

 # Backup overwritten files to a directory
 ./build/client --backup --backup-dir /backups /src user@host:/dst
@@ -303,9 +298,6 @@ Place the `fastsync-server` binary in the remote `$PATH`. The client runs `ssh u
 # Exclude patterns from file, limit depth
 ./build/client --exclude-from ignore.txt --max-depth 3 /src user@host:/dst

-# Custom queue size for multithreading
-./build/client -m --queue-size 200 /src user@host:/dst
-
 # Log to file
 ./build/client --log-file /tmp/fastsync.log /src user@host:/dst

@@ -332,7 +324,7 @@ The benchmark prints throughput metrics, best configuration, and speedup vs rsyn
 1. Chunk size (~10 MB default) balances memory and transfer efficiency
 2. Compression level trades CPU for bandwidth
 3. `sendfile()` bypasses userspace — ~2× faster on localhost for large files
-4. Multithreading scales with core count; `--queue-size` controls pipeline buffering
+4. Multithreading scales with core count and uses memory-based pipeline sizing
 5. Metadata transfer adds negligible overhead (~24 bytes per file when enabled)
 6. SSH socketpair buffer set to 1 MB for improved pipe throughput
 7. SSH ControlMaster reuses connections across repeated invocations
@@ -6,10 +6,10 @@ This document maps rsync's full feature set to FastSync's current implementation

 | Status | Count | Description |
 |--------|-------|-------------|
-| ✅ Implemented | 39 | Feature works end-to-end |
-| 🔀 Alt Arg | 5 | Functionality exists but under different flag/semantics |
-| ⚠️ Partial | 30 | Flag parsed/stored but behavior incomplete |
-| ❌ Not Implemented | 62 | Flag not recognized or no behavior |
+| ✅ Implemented | 34 | Feature works end-to-end |
+| 🔀 Alt Arg | 3 | Functionality exists but under different flag/semantics |
+| ⚠️ Partial | 1 | Flag parsed/stored but behavior incomplete |
+| ❌ Not Implemented | 98 | Flag not recognized or no behavior |
 | **Total** | **136** | |

 ---
@@ -20,31 +20,31 @@ This document maps rsync's full feature set to FastSync's current implementation
 |------|-------------------|-----------------|-------|
 | `-a`, `--archive` | Archive mode is -rlptgoD | 🔀 Alt Arg | Maps to -c -m -M (compression + multithread + metadata) |
 | `-v`, `--verbose` | Increase verbosity | ✅ Implemented | Sets `log_level=DEBUG` |
-| `-q`, `--quiet` | Suppress non-error messages | ✅ Implemented | `quiet` config field |
-| `-h`, `--help` | Show help | ✅ Implemented | Prints usage and exits |
-| `-V`, `--version` | Print version | ❌ Not Implemented | |
-| `--info=FLAGS` | Fine-grained info verbosity | ⚠️ Partial | `info_level` stored, not wired |
-| `--debug=FLAGS` | Fine-grained debug verbosity | ⚠️ Partial | `debug_level` stored, not wired |
+| `-q`, `--quiet` | Suppress non-error messages | ❌ Not Implemented | Removed because it had no effect |
+| `--help` | Show help | ✅ Implemented | Prints usage and exits; `-h` is not accepted |
+| `-V`, `--version` | Print version | ✅ Implemented | |
+| `--info=FLAGS` | Fine-grained info verbosity | ❌ Not Implemented | Removed because it had no effect |
+| `--debug=FLAGS` | Fine-grained debug verbosity | ❌ Not Implemented | Removed because it had no effect |
 | `--stderr=MODE` | Change stderr output mode | ❌ Not Implemented | |
 | `--no-motd` | Suppress daemon MOTD | ❌ Not Implemented | |
 | `--exclude=PATTERN` | Exclude files matching pattern | ✅ Implemented | Glob matching in scanner |
 | `--include=PATTERN` | Include files matching pattern | ✅ Implemented | Glob matching in scanner |
-| `-C`, `--cvs-exclude` | Auto-ignore CVS files | ⚠️ Partial | `cvs_exclude` stored, not wired |
+| `-C`, `--cvs-exclude` | Auto-ignore CVS files | ❌ Not Implemented | Removed because it had no effect |

 ## 2. Modifying Output

 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--stats` | Give transfer stats | ✅ Implemented | Prints file/byte counts |
-| `-h`, `--human-readable` | Human-readable numbers | ⚠️ Partial | `human_readable` stored, not wired |
-| `-i`, `--itemize-changes` | Per-file change summary | ⚠️ Partial | `itemize_changes` stored, not wired |
+| `-h`, `--human-readable` | Human-readable numbers | ❌ Not Implemented | Removed because it had no effect |
+| `-i`, `--itemize-changes` | Per-file change summary | ❌ Not Implemented | Removed because it had no effect |
 | `--progress` | Show progress | ✅ Implemented | Progress callback in sender |
 | `-P` | Same as --partial --progress | ❌ Not Implemented | |
-| `--out-format=FORMAT` | Custom output format | ⚠️ Partial | `out_format` stored, not wired |
+| `--out-format=FORMAT` | Custom output format | ❌ Not Implemented | Removed because it had no effect |
 | `--log-file=FILE` | Log to file | ✅ Implemented | `log_file` config field |
 | `--log-file-format=FMT` | Log format | ❌ Not Implemented | |
 | `--8-bit-output` | Leave high-bit chars unescaped | ❌ Not Implemented | |
-| `--list-only` | List files instead of copying | ⚠️ Partial | `list_only` stored, not wired |
+| `--list-only` | List files instead of copying | ❌ Not Implemented | Removed because it had no effect |

 ## 3. File Selection

@@ -52,8 +52,8 @@ This document maps rsync's full feature set to FastSync's current implementation
 |------|-------------------|-----------------|-------|
 | `--exclude-from=FILE` | Read exclude patterns from file | ✅ Implemented | Reads patterns from file |
 | `--include-from=FILE` | Read include patterns from file | ✅ Implemented | Reads patterns from file |
-| `--filter=RULE` | Add file-filtering rule | ⚠️ Partial | `filters` ArrayList stored, not wired |
-| `--files-from=FILE` | Read source file list from file | ⚠️ Partial | `files_from` stored, not wired |
+| `--filter=RULE` | Add file-filtering rule | ❌ Not Implemented | Removed because it had no effect |
+| `--files-from=FILE` | Read source file list from file | ❌ Not Implemented | Removed because it had no effect |
 | `-0`, `--from0` | Delimit *-from files with NULs | ❌ Not Implemented | |
 | `--max-size=SIZE` | Skip files larger than SIZE | ✅ Implemented | `max_size` in scanner |
 | `--min-size=SIZE` | Skip files smaller than SIZE | ✅ Implemented | `min_size` in scanner |
@@ -69,7 +69,7 @@ This document maps rsync's full feature set to FastSync's current implementation
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-r`, `--recursive` | Recurse into directories | ✅ Implemented | Default behavior |
-| `-R`, `--relative` | Use relative path names | ⚠️ Partial | `relative` stored, not wired |
+| `-R`, `--relative` | Use relative path names | ❌ Not Implemented | Removed because it had no effect |
 | `--no-implied-dirs` | Don't send implied dirs with -R | ❌ Not Implemented | |
 | `-d`, `--dirs` | Transfer dirs without recursing | ❌ Not Implemented | |
 | `--mkpath` | Create missing path components | ❌ Not Implemented | |
@@ -78,10 +78,10 @@ This document maps rsync's full feature set to FastSync's current implementation

 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
-| `-u`, `--update` | Skip files newer on receiver | ⚠️ Partial | `update` stored, not wired |
+| `-u`, `--update` | Skip files newer on receiver | ❌ Not Implemented | Removed because it had no effect |
 | `--inplace` | Update files in-place | ✅ Implemented | Direct write mode |
-| `--append` | Append data to shorter files | ⚠️ Partial | `append` stored, not wired |
-| `--append-verify` | Append with old-data checksum | ⚠️ Partial | `append_verify` stored, not wired |
+| `--append` | Append data to shorter files | ❌ Not Implemented | Removed because it had no effect |
+| `--append-verify` | Append with old-data checksum | ❌ Not Implemented | Removed because it had no effect |
 | `-W`, `--whole-file` | Copy whole file (no delta) | ❌ Not Implemented | |
 | `--block-size=SIZE` | Force checksum block-size | ⚠️ Partial | Parsed as `--delta-block`; controls delta transfer block size |

@@ -100,15 +100,15 @@ This document maps rsync's full feature set to FastSync's current implementation
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--delete` | Delete extraneous files from dest | ✅ Implemented | `use_delete` config field |
-| `--delete-before` | Delete before transfer | ⚠️ Partial | `delete_before` stored, not wired |
+| `--delete-before` | Delete before transfer | ❌ Not Implemented | Removed because it had no effect |
 | `--delete-during` | Delete during transfer | ❌ Not Implemented | |
 | `--delete-delay` | Find deletions during, delete after | ❌ Not Implemented | |
-| `--delete-after` | Delete after transfer | ⚠️ Partial | `delete_after` stored, not wired |
-| `--delete-excluded` | Also delete excluded files | ⚠️ Partial | `delete_excluded` stored, not wired |
-| `--max-delete=NUM` | Max files to delete | ⚠️ Partial | `max_delete` stored, not wired |
+| `--delete-after` | Delete after transfer | ❌ Not Implemented | Removed because it had no effect |
+| `--delete-excluded` | Also delete excluded files | ❌ Not Implemented | Removed because it had no effect |
+| `--max-delete=NUM` | Max files to delete | ❌ Not Implemented | Removed because it had no effect |
 | `--ignore-errors` | Delete even with I/O errors | ❌ Not Implemented | |
 | `--force` | Force deletion of non-empty dirs | ❌ Not Implemented | |
-| `--prune-empty-dirs` | Prune empty dir chains | ⚠️ Partial | `prune_empty_dirs` stored, not wired |
+| `--prune-empty-dirs` | Prune empty dir chains | ❌ Not Implemented | Removed because it had no effect |

 ## 8. Metadata Preservation

@@ -121,11 +121,11 @@ This document maps rsync's full feature set to FastSync's current implementation
 | `-t`, `--times` | Preserve modification times | ✅ Implemented | Part of -M |
 | `-E`, `--executability` | Preserve executability | ❌ Not Implemented | |
 | `--chmod=CHMOD` | Affect file permissions | ❌ Not Implemented | |
-| `-A`, `--acls` | Preserve ACLs | ⚠️ Partial | `preserve_acls` stored, not wired |
-| `-X`, `--xattrs` | Preserve extended attributes | ⚠️ Partial | `preserve_xattrs` stored, not wired |
-| `-H`, `--hard-links` | Preserve hard links | ⚠️ Partial | `preserve_hard_links` stored, not wired |
-| `-D` | Same as --devices --specials | 🔀 Alt Arg | Maps to --devices only (no --specials) |
-| `--devices` | Preserve device files | ⚠️ Partial | `preserve_devices` stored, not wired |
+| `-A`, `--acls` | Preserve ACLs | ❌ Not Implemented | Removed because it had no effect |
+| `-X`, `--xattrs` | Preserve extended attributes | ❌ Not Implemented | Removed because it had no effect |
+| `-H`, `--hard-links` | Preserve hard links | ❌ Not Implemented | Removed because it had no effect |
+| `-D` | Same as --devices --specials | ❌ Not Implemented | Removed because device-file handling is not implemented |
+| `--devices` | Preserve device files | ❌ Not Implemented | Removed because it had no effect |
 | `--specials` | Preserve special files | ❌ Not Implemented | |
 | `--copy-devices` | Copy device contents as file | ❌ Not Implemented | |
 | `--write-devices` | Write to devices as files | ❌ Not Implemented | |
@@ -159,11 +159,11 @@ This document maps rsync's full feature set to FastSync's current implementation

 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
-| `-c`, `--checksum` | Skip based on checksum | 🔀 Alt Arg | `-c` means compression; `--checksum` stored and forwarded to scanner |
+| `--checksum` | Skip based on checksum | ❌ Not Implemented | Removed because it had no effect; `-c` means compression |
 | `--checksum-choice=STR` | Choose checksum algorithm | ❌ Not Implemented | xxHash used internally |
-| `--compare-dest=DIR` | Compare dest files relative to DIR | ⚠️ Partial | `compare_dest` stored, not wired |
-| `--copy-dest=DIR` | Include copies of unchanged files | ⚠️ Partial | `copy_dest` stored, not wired |
-| `--link-dest=DIR` | Hardlink to files when unchanged | ⚠️ Partial | `link_dest` stored, not wired |
+| `--compare-dest=DIR` | Compare dest files relative to DIR | ❌ Not Implemented | Removed because it had no effect |
+| `--copy-dest=DIR` | Include copies of unchanged files | ❌ Not Implemented | Removed because it had no effect |
+| `--link-dest=DIR` | Hardlink to files when unchanged | ❌ Not Implemented | Removed because it had no effect |
 | `--fuzzy`, `--no-fuzzy` | Find similar file for basis | ❌ Not Implemented | |

 ## 12. Compression
@@ -171,7 +171,7 @@ This document maps rsync's full feature set to FastSync's current implementation
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-z`, `--compress` | Compress file data | 🔀 Alt Arg | Always uses zstd (rsync supports multiple algorithms) |
-| `--compress-choice=STR` | Choose compression algorithm | ⚠️ Partial | `compress_choice` stored, always zstd |
+| `--compress-choice=STR` | Choose compression algorithm | ❌ Not Implemented | Removed because it had no effect; FastSync always uses zstd |
 | `--compress-level=NUM` | Set compression level | ✅ Implemented | 1-22, default 5 |
 | `--compress-threads=NUM` | Set compression threads | ❌ Not Implemented | |
 | `--skip-compress=LIST` | Skip compress for suffixes | ❌ Not Implemented | Internal skip for hardcoded types; not user-configurable |
@@ -180,22 +180,22 @@ This document maps rsync's full feature set to FastSync's current implementation

 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
-| `-e`, `--rsh=COMMAND` | Remote shell to use | ✅ Implemented | SSH transport support |
-| `--rsync-path=PROGRAM` | rsync binary on remote | ✅ Implemented | `rsync_path` config field |
+| `-e`, `--rsh=COMMAND` | Remote shell to use | ❌ Not Implemented | Removed; SSH invokes `ssh` directly |
+| `--rsync-path=PROGRAM` | rsync binary on remote | ❌ Not Implemented | Removed; use `--fastsync-server-path` |
 | `--port=PORT` | Alternate daemon port | ✅ Implemented | `server_port` config field |
 | `--sockopts=OPTIONS` | Custom TCP options | ❌ Not Implemented | |
 | `--blocking-io` | Use blocking I/O for remote shell | ❌ Not Implemented | |
 | `--outbuf=N\|L\|B` | Set output buffering | ❌ Not Implemented | |
-| `--address=ADDRESS` | Bind address for outgoing socket | ✅ Implemented | `address` config field |
-| `-4`, `--ipv4` | Prefer IPv4 | ✅ Implemented | `ipv4` config field |
-| `-6`, `--ipv6` | Prefer IPv6 | ✅ Implemented | `ipv6` config field |
+| `--address=ADDRESS` | Bind address for outgoing socket | ❌ Not Implemented | Removed because it had no effect |
+| `-4`, `--ipv4` | Prefer IPv4 | ❌ Not Implemented | Removed because it had no effect |
+| `-6`, `--ipv6` | Prefer IPv6 | ❌ Not Implemented | Removed because it had no effect |

 ## 14. Daemon Mode

 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
-| `--daemon` | Run as rsync daemon | ⚠️ Partial | `daemon` stored, not wired |
-| `--config=FILE` | Alternate rsyncd.conf file | ⚠️ Partial | `daemon_config` stored, not wired |
+| `--daemon` | Run as rsync daemon | ❌ Not Implemented | Removed because it had no effect |
+| `--config=FILE` | Alternate rsyncd.conf file | ❌ Not Implemented | Removed because it had no effect |
 | `--dparam=OVERRIDE` | Override global daemon config | ❌ Not Implemented | |
 | `--no-detach` | Don't detach from parent | ❌ Not Implemented | |
 | `--password-file=FILE` | Read daemon password from file | ❌ Not Implemented | |
@@ -266,7 +266,6 @@ Ranked by user demand, implementation complexity, and interoperability impact:
 | `-f` / `--sendfile` | Zero-copy sendfile() syscall (TCP only) |
 | `-c [level]` | zstd compression level (1-22) |
 | `--chunk-size` | Configurable chunk size |
-| `--queue-size` | Pipeline queue capacity |
 | `--tls` | TLS encryption (mutual auth) |
 | `--fastsync-server-path` | Path to fastsync-server binary |
 | `--server-host` / `--server-port` | Direct TCP connection |
@@ -104,7 +104,7 @@ int parse_args(Config* config, int argc, char* argv[], int* positional_args,
    } else if (strcmp(argv[i], "-n") == 0 || strcmp(argv[i], "--dry-run") == 0) {
      config->dry_run = true;
    } else if (strcmp(argv[i], "-p") == 0 && i + 1 < argc) {
-      if (!set_positive_int_option(&config->ssh_port, argv[++i], "-p"))
+      if (set_positive_int_option(&config->ssh_port, argv[++i], "-p") != 0)
        return -1;
      if (config->ssh_port > 65535) {
        log_message(LOG_LEVEL_ERROR, "SSH port must be 1-65535\n");
@@ -139,8 +139,14 @@ int parse_args(Config* config, int argc, char* argv[], int* positional_args,
      }
      config->include_patterns[config->include_count++] = dup;
    } else if (strcmp(argv[i], "--max-size") == 0 && i + 1 < argc) {
-      if (!set_nonneg_int_option(&config->max_size, argv[++i], "Max Size"))
+      char* end;
+      errno = 0;
+      unsigned long long val = strtoull(argv[++i], &end, 10);
+      if (errno != 0 || *end != '\0') {
+        fprintf(stderr, "Error: --max-size must be a non-negative integer\n");
        return -1;
+      }
+      config->max_size = val;
    } else if (strcmp(argv[i], "--min-size") == 0 && i + 1 < argc) {
      char* end;
      errno = 0;
@@ -268,9 +274,6 @@ int parse_args(Config* config, int argc, char* argv[], int* positional_args,
    } else if (strcmp(argv[i], "--contimeout") == 0 && i + 1 < argc) {
      if (set_positive_int_option(&config->contimeout, argv[++i], "--contimeout") != 0)
        return -1;
-    } else if (strcmp(argv[i], "-q") == 0 || strcmp(argv[i], "--quiet") == 0 ||
-               strcmp(argv[i], "--silent") == 0) {
-      config->quiet = true;
    } else if (strcmp(argv[i], "--backup") == 0) {
      config->backup = true;
    } else if (strcmp(argv[i], "--backup-dir") == 0 && i + 1 < argc) {
@@ -294,9 +297,6 @@ int parse_args(Config* config, int argc, char* argv[], int* positional_args,
      }
      config->log_file = lf;
      log_set_file(lf);
-    } else if (strcmp(argv[i], "--queue-size") == 0 && i + 1 < argc) {
-      if (set_positive_int_option(&config->queue_size, argv[++i], "--queue-size") != 0)
-        return -1;
    } else if (strcmp(argv[i], "--exclude-from") == 0 && i + 1 < argc) {
      if (read_patterns_from_file(argv[++i], &config->exclude_patterns, &config->exclude_count) !=
          0)
@@ -321,118 +321,19 @@ int parse_args(Config* config, int argc, char* argv[], int* positional_args,
      config->safe_links = true;
    } else if (strcmp(argv[i], "--copy-unsafe-links") == 0) {
      config->copy_unsafe_links = true;
-    } else if (strcmp(argv[i], "-H") == 0 || strcmp(argv[i], "--hard-links") == 0) {
-      config->preserve_hard_links = true;
-    } else if (strcmp(argv[i], "-A") == 0 || strcmp(argv[i], "--acls") == 0) {
-      config->preserve_acls = true;
-    } else if (strcmp(argv[i], "-X") == 0 || strcmp(argv[i], "--xattrs") == 0) {
-      config->preserve_xattrs = true;
-    } else if (strcmp(argv[i], "-D") == 0 || strcmp(argv[i], "--devices") == 0) {
-      config->preserve_devices = true;
    } else if (strcmp(argv[i], "-S") == 0 || strcmp(argv[i], "--sparse") == 0) {
      config->preserve_sparse = true;
-    } else if (strcmp(argv[i], "-i") == 0 || strcmp(argv[i], "--itemize-changes") == 0) {
-      config->itemize_changes = true;
-    } else if (strcmp(argv[i], "--out-format") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->out_format, argv[++i], "--out-format") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--info") == 0 && i + 1 < argc) {
-      if (set_nonneg_int_option(&config->info_level, argv[++i], "--info") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--debug") == 0 && i + 1 < argc) {
-      if (set_nonneg_int_option(&config->debug_level, argv[++i], "--debug") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--list-only") == 0) {
-      config->list_only = true;
-    } else if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--human-readable") == 0) {
-      config->human_readable = true;
-    } else if (strcmp(argv[i], "-u") == 0 || strcmp(argv[i], "--update") == 0) {
-      config->update = true;
    } else if (strcmp(argv[i], "--inplace") == 0) {
      config->inplace = true;
-    } else if (strcmp(argv[i], "--append") == 0) {
-      config->append = true;
-    } else if (strcmp(argv[i], "--append-verify") == 0) {
-      config->append_verify = true;
-    } else if (strcmp(argv[i], "--delete-excluded") == 0) {
-      config->delete_excluded = true;
-    } else if (strcmp(argv[i], "--delete-after") == 0) {
-      config->delete_after = true;
-    } else if (strcmp(argv[i], "--max-delete") == 0 && i + 1 < argc) {
-      if (set_nonneg_int_option(&config->max_delete, argv[++i], "--max-delete") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--filter") == 0 && i + 1 < argc) {
-      if (!config->filters)
-        config->filters = array_list_create(free);
-      char* dup = str_dup(argv[++i]);
-      if (!dup)
-        return -1;
-      array_list_add(config->filters, dup);
-    } else if (strcmp(argv[i], "--files-from") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->files_from, argv[++i], "--files-from") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--cvs-exclude") == 0) {
-      config->cvs_exclude = true;
-    } else if (strcmp(argv[i], "--prune-empty-dirs") == 0) {
-      config->prune_empty_dirs = true;
-    } else if (strcmp(argv[i], "-R") == 0 || strcmp(argv[i], "--relative") == 0) {
-      config->relative = true;
-    } else if (strcmp(argv[i], "-e") == 0 || strcmp(argv[i], "--rsh") == 0) {
-      if (i + 1 < argc) {
-        if (set_string_option(&config->rsh_command, argv[++i], "-e/--rsh") != 0)
-          return -1;
-      } else {
-        fprintf(stderr, "Error: -e/--rsh requires a command argument\n");
-        return -1;
-      }
-    } else if (strcmp(argv[i], "--rsync-path") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->rsync_path, argv[++i], "--rsync-path") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--temp-dir") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->temp_dir, argv[++i], "--temp-dir") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--compare-dest") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->compare_dest, argv[++i], "--compare-dest") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--copy-dest") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->copy_dest, argv[++i], "--copy-dest") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--link-dest") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->link_dest, argv[++i], "--link-dest") != 0)
-        return -1;
    } else if (strcmp(argv[i], "--partial-dir") == 0 && i + 1 < argc) {
      if (set_string_option(&config->partial_dir, argv[++i], "--partial-dir") != 0)
        return -1;
    } else if (strcmp(argv[i], "--suffix") == 0 && i + 1 < argc) {
      if (set_string_option(&config->suffix, argv[++i], "--suffix") != 0)
        return -1;
-    } else if (strcmp(argv[i], "--delete-before") == 0) {
-      config->delete_before = true;
    } else if (strcmp(argv[i], "-T") == 0 && i + 1 < argc) {
      if (set_positive_int_option(&config->timeout, argv[++i], "-T") != 0)
        return -1;
-    } else if (strcmp(argv[i], "--address") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->address, argv[++i], "--address") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--bind-address") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->bind_address, argv[++i], "--bind-address") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--ipv6") == 0) {
-      config->ipv6 = true;
-    } else if (strcmp(argv[i], "--ipv4") == 0) {
-      config->ipv4 = true;
-    } else if (strcmp(argv[i], "--daemon") == 0) {
-      config->daemon = true;
-    } else if (strcmp(argv[i], "--config") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->daemon_config, argv[++i], "--config") != 0)
-        return -1;
-    } else if (strcmp(argv[i], "--server") == 0) {
-      config->server_mode = true;
-    } else if (strcmp(argv[i], "--checksum") == 0) {
-      config->checksum = true;
-    } else if (strcmp(argv[i], "--compress-choice") == 0 && i + 1 < argc) {
-      if (set_string_option(&config->compress_choice, argv[++i], "--compress-choice") != 0)
-        return -1;
    } else if (strcmp(argv[i], "--compress-level") == 0 && i + 1 < argc) {
      if (set_positive_int_option(&config->compression_level, argv[++i], "--compress-level") != 0)
        return -1;
@@ -34,7 +34,7 @@ static int send_dry_run_manifest(Config* config) {
      config->send_directory, config->use_metadata, config->chunk_size, config->exclude_patterns,
      config->exclude_count, config->include_patterns, config->include_count, config->max_size,
      config->min_size, config->max_depth, config->follow_symlinks, config->copy_links,
-      config->safe_links, config->copy_unsafe_links, config->checksum);
+      config->safe_links, config->copy_unsafe_links);
  if (!scanner)
    return -1;
  Chunk* chunk;
@@ -375,8 +375,7 @@ static int scan_directory_multithreaded(void* pipeline_context) {
      context->config->exclude_patterns, context->config->exclude_count,
      context->config->include_patterns, context->config->include_count, context->config->max_size,
      context->config->min_size, context->config->max_depth, 4, context->config->follow_symlinks,
-      context->config->copy_links, context->config->safe_links, context->config->copy_unsafe_links,
-      context->config->checksum);
+      context->config->copy_links, context->config->safe_links, context->config->copy_unsafe_links);

  Chunk* current_chunk;
  while ((current_chunk = parallel_scanner_next(scanner)) != NULL) {
@@ -540,7 +539,7 @@ int send_files(Config* config) {
      config->send_directory, config->use_metadata, config->chunk_size, config->exclude_patterns,
      config->exclude_count, config->include_patterns, config->include_count, config->max_size,
      config->min_size, config->max_depth, config->follow_symlinks, config->copy_links,
-      config->safe_links, config->copy_unsafe_links, config->checksum);
+      config->safe_links, config->copy_unsafe_links);
  Chunk* current_chunk;
  unsigned long long total_bytes = 0;
  int total_files = 0;
@@ -44,7 +44,7 @@ DirectoryScanner* directory_scanner_create(const char* root_directory, bool use_
                                           int include_count, unsigned long long max_size,
                                           unsigned long long min_size, int max_depth,
                                           bool follow_symlinks, bool copy_links, bool safe_links,
-                                           bool copy_unsafe_links, bool checksum) {
+                                           bool copy_unsafe_links) {
  DirectoryScanner* scanner = malloc(sizeof(DirectoryScanner));
  if (scanner == NULL)
    return NULL;
@@ -65,7 +65,6 @@ DirectoryScanner* directory_scanner_create(const char* root_directory, bool use_
  scanner->copy_links = copy_links;
  scanner->safe_links = safe_links;
  scanner->copy_unsafe_links = copy_unsafe_links;
-  scanner->checksum = checksum;
  DirEntry* root = dir_entry_create(root_directory, 0);
  if (!root) {
    queue_destroy(scanner->directories);
@@ -292,7 +291,6 @@ typedef struct {
  bool copy_links;
  bool safe_links;
  bool copy_unsafe_links;
-  bool checksum;
 } ParallelWorkerArg;

 static int parallel_worker_thread(void* arg) {
@@ -301,7 +299,7 @@ static int parallel_worker_thread(void* arg) {
    DirectoryScanner* ds = directory_scanner_create(
        wa->dirs[i], wa->use_metadata, wa->chunk_size, wa->exclude_patterns, wa->exclude_count,
        wa->include_patterns, wa->include_count, wa->max_size, wa->min_size, wa->max_depth,
-        wa->follow_symlinks, wa->copy_links, wa->safe_links, wa->copy_unsafe_links, wa->checksum);
+        wa->follow_symlinks, wa->copy_links, wa->safe_links, wa->copy_unsafe_links);
    Chunk* chunk;
    while ((chunk = directory_scanner_next(ds)) != NULL) {
      queue_enqueue_multithreaded(wa->ps->result_queue, chunk, &wa->ps->result_mutex,
@@ -329,7 +327,7 @@ ParallelScanner* parallel_scanner_create(char* root_directory, bool use_metadata
                                         int include_count, unsigned long long max_size,
                                         unsigned long long min_size, int max_depth,
                                         int num_threads, bool follow_symlinks, bool copy_links,
-                                         bool safe_links, bool copy_unsafe_links, bool checksum) {
+                                         bool safe_links, bool copy_unsafe_links) {
  ParallelScanner* ps = calloc(1, sizeof(ParallelScanner));
  if (!ps)
    return NULL;
@@ -562,7 +560,6 @@ ParallelScanner* parallel_scanner_create(char* root_directory, bool use_metadata
      wa->copy_links = copy_links;
      wa->safe_links = safe_links;
      wa->copy_unsafe_links = copy_unsafe_links;
-      wa->checksum = checksum;
      start += count;
      if (thrd_create(&ps->threads[t], parallel_worker_thread, wa) != thrd_success) {
        for (int j = 0; j < count; j++)
@@ -25,7 +25,6 @@ typedef struct {
  bool copy_links;
  bool safe_links;
  bool copy_unsafe_links;
-  bool checksum;
 } DirectoryScanner;

 typedef struct {
@@ -46,7 +45,7 @@ DirectoryScanner* directory_scanner_create(const char* root_directory, bool use_
                                           int include_count, unsigned long long max_size,
                                           unsigned long long min_size, int max_depth,
                                           bool follow_symlinks, bool copy_links, bool safe_links,
-                                           bool copy_unsafe_links, bool checksum);
+                                           bool copy_unsafe_links);
 Chunk* directory_scanner_next(DirectoryScanner* scanner);
 void directory_scanner_destroy(DirectoryScanner* scanner);

@@ -56,7 +55,7 @@ ParallelScanner* parallel_scanner_create(char* root_directory, bool use_metadata
                                         int include_count, unsigned long long max_size,
                                         unsigned long long min_size, int max_depth,
                                         int num_threads, bool follow_symlinks, bool copy_links,
-                                         bool safe_links, bool copy_unsafe_links, bool checksum);
+                                         bool safe_links, bool copy_unsafe_links);
 Chunk* parallel_scanner_next(ParallelScanner* scanner);
 void parallel_scanner_destroy(ParallelScanner* scanner);

@@ -51,19 +51,12 @@ static __attribute__((unused)) void print_usage() {
  printf("  --timeout <sec>     I/O timeout in seconds (default: 30)\n");
  printf("  -T <sec>            Alias for --timeout\n");
  printf("  --contimeout <sec>  Connection timeout in seconds (default: 10)\n");
-  printf("  --address <host>    Server hostname/IP to connect to\n");
-  printf("  --bind-address <ip> Bind to specific local address\n");
-  printf("  --ipv6              Prefer IPv6 connections\n");
-  printf("  --ipv4              Prefer IPv4 connections\n");
-  printf("  -q, --quiet         Suppress non-error output\n");
-  printf("  --silent            Alias for --quiet\n");
  printf("  --backup            Backup existing files before overwriting\n");
  printf("  --backup-dir <dir>  Directory for backups (requires --backup)\n");
  printf("  --suffix <str>      Backup suffix (default: ~)\n");
  printf("  --stats             Print transfer statistics at end\n");
  printf("  --max-depth <n>     Maximum directory depth (0=unlimited)\n");
  printf("  --log-file <path>   Write log messages to file\n");
-  printf("  --queue-size <n>    Queue capacity for multithreaded mode (default: 100)\n");
  printf("  --partial           Keep partial files on interrupted transfer\n");
  printf("  --partial-dir <dir> Directory for partial files\n");
  printf("  --fastsync-server-path <path>\n");
@@ -72,42 +65,9 @@ static __attribute__((unused)) void print_usage() {
  printf("  --copy-links        Transform symlinks into referent files\n");
  printf("  --safe-links        Skip symlinks that point outside transfer tree\n");
  printf("  --copy-unsafe-links  Only transform unsafe symlinks into referent files\n");
-  printf("  -H, --hard-links    Preserve hard links\n");
-  printf("  -A, --acls          Preserve ACLs\n");
-  printf("  -X, --xattrs        Preserve extended attributes\n");
-  printf("  -D, --devices       Preserve device files\n");
  printf("  -S, --sparse        Handle sparse files efficiently\n");
-  printf("  -i, --itemize-changes  Show per-file change summary\n");
-  printf("  --out-format <fmt>  Custom output format string\n");
-  printf("  --info <flags>      Info verbosity level\n");
-  printf("  --debug <flags>     Debug verbosity level\n");
-  printf("  --list-only         List files without transferring\n");
-  printf("  -h, --human-readable  Human-readable numbers\n");
-  printf("  -u, --update        Skip files newer on destination\n");
  printf("  --inplace           Update files in-place (no temp+rename)\n");
-  printf("  --append            Append data to shorter files\n");
-  printf("  --append-verify     Append with verify\n");
-  printf("  --delete-before     Delete before transfer\n");
-  printf("  --delete-excluded   Also delete excluded files\n");
-  printf("  --delete-after      Delete after transfer, not before\n");
-  printf("  --max-delete <n>    Maximum number of files to delete\n");
-  printf("  --filter <rule>     Add file filtering rule\n");
-  printf("  --files-from <file> Read file list from file\n");
-  printf("  --cvs-exclude       Auto-ignore CVS files\n");
-  printf("  --prune-empty-dirs  Omit empty directories from transfer\n");
-  printf("  -R, --relative      Use relative paths\n");
-  printf("  -e, --rsh <cmd>     Specify remote shell\n");
-  printf("  --rsync-path <path> Path to remote binary\n");
-  printf("  --daemon            Run in daemon mode\n");
-  printf("  --config <path>     Path to configuration file\n");
-  printf("  --server            Run in server mode\n");
-  printf("  --checksum          Skip files based on checksum, not mod-time/size\n");
-  printf("  --compress-choice <alg>  Compression algorithm (default: zstd)\n");
  printf("  --compress-level <n>    Compression level (default: 5)\n");
-  printf("  --temp-dir <dir>    Temporary directory for files\n");
-  printf("  --compare-dest <dir>  Compare destination\n");
-  printf("  --copy-dest <dir>   Copy destination\n");
-  printf("  --link-dest <dir>   Link destination\n");
  printf("  --help              Show this help\n");
  printf("  -V, --version       Show version\n");
 }
@@ -45,59 +45,20 @@ static void config_set_defaults(Config* config) {
  config->server_port = 8080;
  config->timeout = 30;
  config->contimeout = 10;
-  config->quiet = false;
  config->backup = false;
  config->backup_dir = NULL;
  config->stats = false;
  config->max_depth = 0;
  config->log_file = NULL;
-  config->queue_size = 100;
  config->follow_symlinks = false;
  config->partial = false;
  config->copy_links = false;
  config->safe_links = false;
  config->copy_unsafe_links = false;
-  config->preserve_hard_links = false;
-  config->preserve_acls = false;
-  config->preserve_xattrs = false;
-  config->preserve_devices = false;
  config->preserve_sparse = false;
-  config->itemize_changes = false;
-  config->out_format = NULL;
-  config->info_level = 0;
-  config->debug_level = 0;
-  config->list_only = false;
-  config->human_readable = false;
-  config->update = false;
  config->inplace = false;
-  config->append = false;
-  config->append_verify = false;
-  config->delete_excluded = false;
-  config->delete_after = false;
-  config->max_delete = 0;
-  config->filters = NULL;
-  config->files_from = NULL;
-  config->cvs_exclude = false;
-  config->prune_empty_dirs = false;
-  config->relative = false;
-  config->rsh_command = NULL;
-  config->rsync_path = NULL;
-  config->temp_dir = NULL;
-  config->compare_dest = NULL;
-  config->copy_dest = NULL;
-  config->link_dest = NULL;
  config->partial_dir = NULL;
  config->suffix = NULL;
-  config->delete_before = false;
-  config->address = NULL;
-  config->bind_address = NULL;
-  config->ipv6 = false;
-  config->ipv4 = false;
-  config->daemon = false;
-  config->daemon_config = NULL;
-  config->server_mode = false;
-  config->checksum = false;
-  config->compress_choice = NULL;
 }

 Config* config_create(void) {
@@ -153,23 +114,8 @@ void config_delete(Config* config) {
  free(config->tls_ca);
  free(config->backup_dir);
  free(config->server_host);
-  free(config->out_format);
-  free(config->files_from);
-  free(config->rsh_command);
-  free(config->rsync_path);
-  free(config->temp_dir);
-  free(config->compare_dest);
-  free(config->copy_dest);
-  free(config->link_dest);
  free(config->partial_dir);
  free(config->suffix);
-  free(config->address);
-  free(config->bind_address);
-  free(config->daemon_config);
-  free(config->compress_choice);
-  if (config->filters) {
-    array_list_delete(config->filters);
-  }
  free(config);
 }

@@ -178,10 +124,11 @@ void config_delete(Config* config) {
 * use_chunk_serialization, use_compression, use_metadata, compression_level, chunk_size,
 * use_sendfile, use_delete, use_incremental, use_delta, delta_block_size, delta_max_file_size,
 * backup, backup_dir, follow_symlinks, copy_links, safe_links, copy_unsafe_links,
- * preserve_hard_links, preserve_acls, preserve_xattrs, preserve_devices, preserve_sparse,
- * update, inplace, append, append_verify, delete_excluded, delete_after, max_delete, relative,
- * prune_empty_dirs, temp_dir, partial, partial_dir, suffix, delete_before, checksum,
- * compress_choice, status
+ * obsolete metadata flags, preserve_sparse, obsolete transfer flags, inplace, obsolete delete
+ * flags, obsolete path options, partial, partial_dir, suffix, obsolete checksum options, status
+ *
+ * Obsolete fields remain as zero/empty compatibility slots. They must be consumed in this order
+ * until the protocol version is intentionally changed.
 */
 bool config_send(int file_descriptor, const Config* config) {
  if (!send_str(file_descriptor, config->version))
@@ -228,35 +175,36 @@ bool config_send(int file_descriptor, const Config* config) {
    return false;
  if (!send_int(file_descriptor, config->copy_unsafe_links))
    return false;
-  if (!send_int(file_descriptor, config->preserve_hard_links))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->preserve_acls))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->preserve_xattrs))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->preserve_devices))
+  if (!send_int(file_descriptor, 0))
    return false;
  if (!send_int(file_descriptor, config->preserve_sparse))
    return false;
-  if (!send_int(file_descriptor, config->update))
+  if (!send_int(file_descriptor, 0))
    return false;
  if (!send_int(file_descriptor, config->inplace))
    return false;
-  if (!send_int(file_descriptor, config->append))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->append_verify))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->delete_excluded))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->delete_after))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_n_data(file_descriptor, &config->max_delete, sizeof(config->max_delete)))
+  int obsolete_int = 0;
+  if (!send_n_data(file_descriptor, &obsolete_int, sizeof(obsolete_int)))
    return false;
-  if (!send_int(file_descriptor, config->relative))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->prune_empty_dirs))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_str(file_descriptor, config->temp_dir ? config->temp_dir : ""))
+  if (!send_str(file_descriptor, ""))
    return false;
  if (!send_int(file_descriptor, config->partial))
    return false;
@@ -264,11 +212,11 @@ bool config_send(int file_descriptor, const Config* config) {
    return false;
  if (!send_str(file_descriptor, config->suffix ? config->suffix : ""))
    return false;
-  if (!send_int(file_descriptor, config->delete_before))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->checksum))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_str(file_descriptor, config->compress_choice ? config->compress_choice : ""))
+  if (!send_str(file_descriptor, ""))
    return false;
  Status status;
  if (!receive_status(file_descriptor, &status))
@@ -374,48 +322,39 @@ Config* config_receive(int file_descriptor) {
  config->copy_unsafe_links = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->preserve_hard_links = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->preserve_acls = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->preserve_xattrs = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->preserve_devices = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->preserve_sparse = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->update = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->inplace = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->append = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->append_verify = tmp;
-  if (!receive_int(file_descriptor, &tmp))
-    goto error;
-  config->delete_excluded = tmp;
-  if (!receive_int(file_descriptor, &tmp))
-    goto error;
-  config->delete_after = tmp;
-  if (!receive_n_data(file_descriptor, &config->max_delete, sizeof(config->max_delete)))
-    goto error;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->relative = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->prune_empty_dirs = tmp;
-  config->temp_dir = receive_str(file_descriptor);
-  if (config->temp_dir == NULL)
+  int obsolete_int = 0;
+  if (!receive_n_data(file_descriptor, &obsolete_int, sizeof(obsolete_int)))
    goto error;
+  if (!receive_int(file_descriptor, &tmp))
+    goto error;
+  if (!receive_int(file_descriptor, &tmp))
+    goto error;
+  char* obsolete_string = receive_str(file_descriptor);
+  if (obsolete_string == NULL)
+    goto error;
+  free(obsolete_string);
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->partial = tmp;
@@ -427,13 +366,12 @@ Config* config_receive(int file_descriptor) {
    goto error;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->delete_before = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->checksum = tmp;
-  config->compress_choice = receive_str(file_descriptor);
-  if (config->compress_choice == NULL)
+  obsolete_string = receive_str(file_descriptor);
+  if (obsolete_string == NULL)
    goto error;
+  free(obsolete_string);
  if (!send_status(file_descriptor, STATUS_OK))
    goto error;
  return config;
@@ -444,10 +382,8 @@ error:
  free(config->receive_root_directory);
  free(config->server_host);
  free(config->backup_dir);
-  free(config->temp_dir);
  free(config->partial_dir);
  free(config->suffix);
-  free(config->compress_choice);
  free(config);
  return NULL;
 }
@@ -1,7 +1,6 @@
 #ifndef CONFIG_H
 #define CONFIG_H

-#include "array_list.h"
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
@@ -45,13 +44,11 @@ typedef struct Config {
  char* tls_ca;
  int timeout;
  int contimeout;
-  bool quiet;
  bool backup;
  char* backup_dir;
  bool stats;
  int max_depth;
  FILE* log_file;
-  int queue_size;
  bool follow_symlinks;
  bool partial;

@@ -60,46 +57,9 @@ typedef struct Config {
  bool safe_links;
  bool copy_unsafe_links;

-  // Issue #121: Extended metadata preservation
-  bool preserve_hard_links;
-  bool preserve_acls;
-  bool preserve_xattrs;
-  bool preserve_devices;
  bool preserve_sparse;

-  // Issue #122: Output/logging options
-  bool itemize_changes;
-  char* out_format;
-  int info_level;
-  int debug_level;
-  bool list_only;
-  bool human_readable;
-
-  // Issue #127: Transfer modes
-  bool update;
  bool inplace;
-  bool append;
-  bool append_verify;
-
-  // Issue #128: Extended delete options
-  bool delete_excluded;
-  bool delete_after;
-  int max_delete;
-
-  // Issue #129: Advanced file selection
-  ArrayList* filters;
-  char* files_from;
-  bool cvs_exclude;
-  bool prune_empty_dirs;
-  bool relative;
-
-  // Issue #130: Remote shell/connection options
-  char* rsh_command;
-  char* rsync_path;
-  char* temp_dir;
-  char* compare_dest;
-  char* copy_dest;
-  char* link_dest;

  // PR #174: Partial transfer resumption
  char* partial_dir;
@@ -107,25 +67,6 @@ typedef struct Config {
  // PR #178: Backup versioning
  char* suffix;

-  // PR #179: Delete policies
-  bool delete_before;
-
-  // PR #181: IPv6 and bind address
-  char* address;
-  char* bind_address;
-  bool ipv6;
-  bool ipv4;
-
-  // PR #182: Daemon/server mode
-  bool daemon;
-  char* daemon_config;
-  bool server_mode;
-
-  // PR #183: Checksum comparison
-  bool checksum;
-
-  // PR #184: Compression algorithm negotiation
-  char* compress_choice;
 } Config;

 /* This version must be bumped whenever config_send / config_receive wire format changes. */
@@ -207,6 +207,34 @@ static void test_parse_args_unknown_option() {
  config_delete(cfg);
 }

+/* Parsed-but-unimplemented options must fail instead of being silently accepted. */
+static void test_parse_args_rejects_unimplemented_options() {
+  static const char* const options[] = {
+      "-q",       "--quiet",          "--silent",          "--queue-size",
+      "-H",       "--hard-links",     "-A",                "--acls",
+      "-X",       "--xattrs",         "-D",                "--devices",
+      "-i",       "--itemize-changes", "--out-format",     "--info",
+      "--debug",  "--list-only",      "-h",                "--human-readable",
+      "-u",       "--update",         "--append",          "--append-verify",
+      "--delete-excluded", "--delete-after", "--max-delete", "--filter",
+      "--files-from", "--cvs-exclude", "--prune-empty-dirs", "-R",
+      "--relative", "-e",             "--rsh",             "--rsync-path",
+      "--temp-dir", "--compare-dest",  "--copy-dest",       "--link-dest",
+      "--delete-before", "--address",  "--bind-address",    "--ipv6",
+      "--ipv4",   "--daemon",         "--config",          "--server",
+      "--checksum", "--compress-choice"};
+
+  for (size_t i = 0; i < sizeof(options) / sizeof(options[0]); i++) {
+    Config* cfg = config_create();
+    char* argv[] = {"fastsync", (char*)options[i], "dummy", "/src", "/dst"};
+    int positional_args[2];
+    int positional_count = 0;
+
+    EXPECT_EQ_INT(parse_args(cfg, 5, argv, positional_args, &positional_count), -1);
+    config_delete(cfg);
+  }
+}
+
 /* Test parse_args with --archive flag */
 static void test_parse_args_archive() {
  Config* cfg = config_create();
@@ -238,5 +266,6 @@ void test_client_cli() {
  test_parse_args_invalid_compression_level();
  test_parse_args_valid_compression_level();
  test_parse_args_unknown_option();
+  test_parse_args_rejects_unimplemented_options();
  test_parse_args_archive();
 }
@@ -19,7 +19,7 @@ static void test_scanner_single_file() {
  create_test_file(file1, content1);

  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 0,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  Chunk* chunk = directory_scanner_next(scanner);
@@ -48,7 +48,7 @@ static void test_scanner_multiple_files() {
  create_test_file(file2, content2);

  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 0,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  const Chunk* chunk = directory_scanner_next(scanner);
@@ -88,7 +88,7 @@ static void test_scanner_subdirectory() {
  create_test_file(sub_file, content);

  DirectoryScanner* scanner = directory_scanner_create((char*)root, false, 0, NULL, 0, NULL, 0, 0,
-                                                       0, 0, false, false, false, false, false);
+                                                       0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  int total_files = 0;
@@ -112,7 +112,7 @@ static void test_scanner_empty_directory() {
  EXPECT_EQ_INT(mkdir(dir, 0755), 0);

  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 0,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  const Chunk* chunk = directory_scanner_next(scanner);
@@ -136,7 +136,7 @@ static void test_scanner_exclude_pattern() {

  char* exclude[] = {"*.tmp"};
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, exclude, 1, NULL, 0, 0,
-                                                       0, 0, false, false, false, false, false);
+                                                       0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  Chunk* chunk = directory_scanner_next(scanner);
@@ -169,7 +169,7 @@ static void test_scanner_exclude_subdirectory() {

  char* exclude[] = {"*.tmp"};
  DirectoryScanner* scanner = directory_scanner_create((char*)root, false, 0, exclude, 1, NULL, 0,
-                                                       0, 0, 0, false, false, false, false, false);
+                                                       0, 0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  int total = 0;
@@ -207,7 +207,7 @@ static void test_scanner_include_and_exclude() {
  char* exclude[] = {"*.bak"};
  char* include[] = {"*.txt", "*.log"};
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, exclude, 1, include, 2,
-                                                       0, 0, 0, false, false, false, false, false);
+                                                       0, 0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  Chunk* chunk = directory_scanner_next(scanner);
@@ -244,7 +244,7 @@ static void test_scanner_max_size() {

  /* max_size = 10 — only files <= 10 bytes */
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 10,
-                                                       0, 0, false, false, false, false, false);
+                                                       0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  Chunk* chunk = directory_scanner_next(scanner);
@@ -272,7 +272,7 @@ static void test_scanner_min_size() {

  /* min_size = 1 — only files >= 1 byte */
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 1,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  Chunk* chunk = directory_scanner_next(scanner);
@@ -302,7 +302,7 @@ static void test_scanner_size_range() {

  /* Only files between 3 and 20 bytes */
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 20,
-                                                       3, 0, false, false, false, false, false);
+                                                       3, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  Chunk* chunk = directory_scanner_next(scanner);
@@ -338,7 +338,7 @@ static void test_scanner_mixed_patterns() {
  char* exclude[] = {"*.bak"};
  char* include[] = {"*.txt"};
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, exclude, 1, include, 1,
-                                                       10, 3, 0, false, false, false, false, false);
+                                                       10, 3, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  Chunk* chunk = directory_scanner_next(scanner);
@@ -369,7 +369,7 @@ static void test_scanner_no_patterns() {
  create_test_file(f2, "second");

  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 0,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);

  Chunk* chunk = directory_scanner_next(scanner);