An open source utility that provides fast incremental file transfer. It also has useful features for backup and restore operations among many other use cases.
This report presents the forensic synthetic code analysis of RsyncProject/rsync, a C project with 5,073 GitHub stars. SynthScan v2.0 examined 103,000 lines of code across 314 source files, recording 311 pattern matches distributed across 12 syntactic categories. The overall adjusted score of 4.2 places this repository in the Likely human-written band.
The scanner applied 160+ deterministic lexical heuristics, multi-line block detectors, abstract syntax tree depth profilers, and a cross-file Jaccard similarity matrix to construct a statistically normalised synthetic code estimate. All matches are individually weighted by severity coefficient and contextual multiplier before summation, and the resulting headline score is temporally discounted to account for the repository's development history relative to the commercial emergence of large language model coding tooling (November 2022 onward).
Longitudinal tracking requires multiple scan runs. Once this repository is re-scanned after new commits land, this chart will visualise how the synthetic code signal evolves over time — enabling you to detect whether AI authorship is growing, stabilising, or being actively corrected by human engineers.
Classifies detected patterns by their diagnostic confidence and structural impact. CRITICAL patterns (coefficient 10) represent definitive synthetic signatures — hallucinated imports, explicit LLM attribution metadata — virtually never produced by human authors. HIGH (5) indicates strong structural tells such as cross-file repetition or cross-linguistic idioms. MEDIUM (2) covers recognisable conversational padding and AI-specific vocabulary. LOW (1) captures subtle indicators like tautological comments and generic boilerplate that require density to carry independent signal.
This horizontal bar chart decomposes the repository's raw synthetic code score by top-level directory, allowing you to pinpoint precisely which modules or components carry the highest AI authorship density. Directories with disproportionately high scores relative to their size warrant targeted manual review: concentrated AI signatures often trace back to mass-generated configuration layers, auto-ported test suites, LLM-scaffolded boilerplate classes, or entire subsystems authored under heavy copilot assistance. Use this view to prioritise your human code-review effort.
The scanner identified 311 distinct pattern matches across 12 syntactic categories. Each entry below represents a discrete location in the source code where the engine recorded a statistically significant AI authorship indicator. Expand any category row to inspect the individual file paths, line numbers, code snippets, and the lexical context (CODE, COMMENT, or STRING) in which each match was detected.
Reading the findings table: The Severity column indicates the diagnostic confidence level (CRITICAL / HIGH / MEDIUM / LOW). The Context column identifies whether the match occurred inside executable code, an inline comment, or a string literal — comment-context matches receive a ×1.5 weight because LLMs systematically over-annotate. The ⚡ bolt icon marks clustered matches: three or more patterns within a 10-line window, each receiving an additional ×1.5 density multiplier as dense clusters constitute far stronger evidence of synthetic authorship than isolated hits.
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | errcode.h | 21 | /* If you change these, please also update the string mappings in log.c and | COMMENT |
| LOW | errcode.h | 61 | #define RERR_CMD_FAILED 124 | COMMENT |
| LOW | version.h | 1 | #define RSYNC_VERSION "3.5.0dev" | COMMENT |
| LOW | loadparm.c | 101 | #endif | COMMENT |
| LOW | loadparm.c | 121 | { LOG_MAIL, "mail" }, | COMMENT |
| LOW | loadparm.c | 141 | #ifdef LOG_LOCAL1 | COMMENT |
| LOW | rsync.h | 21 | #define False 0 | COMMENT |
| LOW | rsync.h | 41 | /* a non-zero CHAR_OFFSET makes the rolling sum stronger, but is | COMMENT |
| LOW | rsync.h | 61 | #define XMIT_USER_NAME_FOLLOWS (1<<10) /* protocols 30 - now */ | COMMENT |
| LOW | rsync.h | 81 | #define FLAG_CONTENT_DIR (1<<2) /* sender/receiver/generator */ | COMMENT |
| LOW | rsync.h | 141 | * MAX_PROTOCOL_VERSION: either to allow new major-rev versions that | COMMENT |
| LOW | rsync.h | 201 | #define LINK_DEST 3 | COMMENT |
| LOW | rsync.h | 221 | #define MSG_FLUSH 2 | COMMENT |
| LOW | rsync.h | 241 | #define ITEM_REPORT_TIME (1<<3) | COMMENT |
| LOW | rsync.h | 301 | MSG_NO_SEND=102,/* sender failed to open a file we wanted */ | COMMENT |
| LOW | rsync.h | 341 | COMMENT | |
| LOW | rsync.h | 361 | # include <memory.h> | COMMENT |
| LOW | rsync.h | 381 | #ifdef HAVE_SYS_PARAM_H | COMMENT |
| LOW | rsync.h | 401 | #ifdef HAVE_SYS_FCNTL_H | COMMENT |
| LOW | rsync.h | 421 | #ifdef HAVE_GRP_H | COMMENT |
| LOW | rsync.h | 441 | COMMENT | |
| LOW | rsync.h | 461 | #endif | COMMENT |
| LOW | rsync.h | 481 | #ifdef HAVE_SYS_FILE_H | COMMENT |
| LOW | rsync.h | 501 | #include <sys/mkdev.h> | COMMENT |
| LOW | rsync.h | 521 | #ifdef __TANDEM | COMMENT |
| LOW | rsync.h | 541 | #define ICONV_CONST | COMMENT |
| LOW | rsync.h | 561 | typedef unsigned int id_t; | COMMENT |
| LOW | rsync.h | 581 | #define uchar unsigned char | COMMENT |
| LOW | rsync.h | 601 | #else | COMMENT |
| LOW | rsync.h | 621 | #elif SIZEOF_INT == 4 | COMMENT |
| LOW | rsync.h | 641 | #endif | COMMENT |
| LOW | rsync.h | 661 | COMMENT | |
| LOW | rsync.h | 681 | # define int64 off64_t | COMMENT |
| LOW | rsync.h | 721 | #define HT_NODE(tbl, bkts, i) ((void*)((char*)(bkts) + (i)*(tbl)->node_size)) | COMMENT |
| LOW | rsync.h | 741 | #ifndef MAXPATHLEN | COMMENT |
| LOW | rsync.h | 761 | #ifndef INADDR_NONE | COMMENT |
| LOW | rsync.h | 781 | #define PREALLOCATE_NEEDS_TRUNCATE 1 | COMMENT |
| LOW | rsync.h | 841 | extern int pathname_ndx; | COMMENT |
| LOW | rsync.h | 861 | #define OPT_EXTRA(f,bump) ((union file_extras*)(f) - file_extra_cnt - 1 - (bump)) | COMMENT |
| LOW | rsync.h | 881 | #define F_MOD_NSEC(f) OPT_EXTRA(f, 0)->unum | COMMENT |
| LOW | rsync.h | 901 | #define F_XATTR(f) REQ_EXTRA(f, xattrs_ndx)->num | COMMENT |
| LOW | rsync.h | 921 | #define F_SUM(f) ((char*)OPT_EXTRA(f, START_BUMP(f) + HLINK_BUMP(f) \ | COMMENT |
| LOW | rsync.h | 1021 | #define FILTRULE_DIRECTORY (1<<6) /* this matches only directories */ | COMMENT |
| LOW | rsync.h | 1101 | } xbuf; | COMMENT |
| LOW | rsync.h | 1121 | #define RL_EOL_NULLS (1<<0) | COMMENT |
| LOW | rsync.h | 1141 | #include "lib/mdigest.h" | COMMENT |
| LOW | rsync.h | 1161 | time_t crtime; | COMMENT |
| LOW | rsync.h | 1201 | #define read_buf read_buf_ | COMMENT |
| LOW | rsync.h | 1221 | #endif | COMMENT |
| LOW | rsync.h | 1241 | #endif | COMMENT |
| LOW | rsync.h | 1261 | #define SIGACTION(n,h) signal(n,h) | COMMENT |
| LOW | rsync.h | 1281 | #define S_IRUSR 0400 | COMMENT |
| LOW | rsync.h | 1301 | COMMENT | |
| LOW | rsync.h | 1321 | #else | COMMENT |
| LOW | rsync.h | 1341 | COMMENT | |
| LOW | rsync.h | 1401 | #endif | COMMENT |
| LOW | rsync.h | 1421 | #define MY_UID() geteuid() | COMMENT |
| LOW | rsync.h | 1441 | #define DEBUG_GTE(flag, lvl) (debug_levels[DEBUG_##flag] >= (lvl)) | COMMENT |
| LOW | rsync.h | 1461 | #define DEBUG_BACKUP (DEBUG_ACL+1) | COMMENT |
| LOW | rsync.h | 1481 | #define DEBUG_RECV (DEBUG_PROTO+1) | COMMENT |
| 118 more matches not shown… | ||||
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| MEDIUM | testsuite/abdiff.py | 44 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/abdiff.py | 136 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/abdiff.py | 270 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/abdiff.py | 495 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/abdiff.py | 544 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/abdiff.py | 715 | # =========================================================================== | COMMENT |
| MEDIUM | testsuite/abdiff.py | 722 | # =========================================================================== | COMMENT |
| MEDIUM | testsuite/abdiff.py | 2475 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/perftest.py | 47 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/perftest.py | 49 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/perftest.py | 229 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/perftest.py | 231 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/perftest.py | 322 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/perftest.py | 324 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/perftest.py | 390 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/perftest.py | 392 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM⚡ | testsuite/fleettest.py | 189 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM⚡ | testsuite/fleettest.py | 191 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM⚡ | testsuite/fleettest.py | 731 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM⚡ | testsuite/fleettest.py | 733 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 236 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 238 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 256 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 258 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 280 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 282 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 344 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 346 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 444 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 446 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 542 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 544 | # --------------------------------------------------------------------------- | COMMENT |
| MEDIUM | testsuite/fleettest.py | 868 | # --------------------------------------------------------------------------- | STRING |
| MEDIUM | testsuite/fleettest.py | 870 | # --------------------------------------------------------------------------- | STRING |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| HIGH⚡ | testsuite/fleettest.py | 190 | # command execution (ssh for remote, local shell when ssh_host is null) | COMMENT |
| HIGH⚡ | testsuite/fleettest.py | 787 | command -v pgrep >/dev/null 2>&1 || return 0 | CODE |
| HIGH⚡ | testsuite/fleettest.py | 789 | [ "$before" -gt 0 ] 2>/dev/null || return 0 | CODE |
| HIGH⚡ | testsuite/fleettest.py | 795 | [ "$killed" -gt 0 ] 2>/dev/null && echo "KILLED $killed stray $1(s)" | CODE |
| HIGH⚡ | testsuite/fleettest.py | 796 | if [ "$after" -gt 0 ] 2>/dev/null; then | CODE |
| HIGH⚡ | testsuite/fleettest.py | 805 | if rm -rf -- "$d" 2>/dev/null || sudo -n rm -rf -- "$d" 2>/dev/null; then | CODE |
| HIGH⚡ | testsuite/fleettest.py | 805 | if rm -rf -- "$d" 2>/dev/null || sudo -n rm -rf -- "$d" 2>/dev/null; then | CODE |
| HIGH | testsuite/fleettest.py | 294 | f'{t.make} -j{t.pipe_jobs} check-progs || exit 5\n' | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | packaging/release.py | 19 | CODE | |
| LOW | packaging/release.py | 24 | CODE | |
| LOW | packaging/release.py | 24 | CODE | |
| LOW | packaging/release.py | 24 | CODE | |
| LOW | testsuite/filter-depth_test.py | 11 | CODE | |
| LOW | testsuite/filter-depth_test.py | 13 | CODE | |
| LOW | testsuite/metadata-depth_test.py | 13 | CODE | |
| LOW | testsuite/exclude_test.py | 17 | CODE | |
| LOW | testsuite/exclude_test.py | 17 | CODE | |
| LOW | testsuite/ssh-basic_test.py | 41 | CODE | |
| LOW | testsuite/acls_test.py | 9 | CODE | |
| LOW | testsuite/hardlinks_test.py | 14 | CODE | |
| LOW | testsuite/files-from_test.py | 8 | CODE | |
| LOW | testsuite/daemon-refuse_test.py | 12 | CODE | |
| LOW | testsuite/rsyncfns.py | 18 | CODE | |
| LOW | testsuite/missing_test.py | 12 | CODE | |
| LOW | testsuite/abdiff.py | 25 | CODE | |
| LOW | testsuite/dir-sgid_test.py | 9 | CODE | |
| LOW | testsuite/acls-depth_test.py | 10 | CODE | |
| LOW | testsuite/symlink-dirlink-basis_test.py | 20 | CODE | |
| LOW | testsuite/daemon_test.py | 16 | CODE | |
| LOW | testsuite/daemon_test.py | 16 | CODE | |
| LOW | testsuite/daemon_test.py | 16 | CODE | |
| LOW | testsuite/itemize_test.py | 11 | CODE | |
| LOW | testsuite/itemize_test.py | 11 | CODE | |
| LOW | testsuite/batch-mode_test.py | 8 | CODE | |
| LOW | testsuite/fleettest.py | 67 | CODE | |
| LOW | testsuite/delete-deep_test.py | 11 | CODE | |
| LOW | testsuite/size-filter_test.py | 9 | CODE | |
| LOW | testsuite/chmod-option_test.py | 10 | CODE | |
| LOW | testsuite/backup_test.py | 12 | CODE | |
| LOW | testsuite/00-hello_test.py | 10 | CODE | |
| LOW | testsuite/devices_test.py | 14 | CODE | |
| LOW | testsuite/devices_test.py | 14 | CODE | |
| LOW | testsuite/devices_test.py | 14 | CODE | |
| LOW | testsuite/devices_test.py | 14 | CODE | |
| LOW | testsuite/devices_test.py | 14 | CODE | |
| LOW | testsuite/proxy-response-line-too-long_test.py | 16 | CODE | |
| LOW | testsuite/chdir-symlink-race_test.py | 15 | CODE | |
| LOW | testsuite/chdir-symlink-race_test.py | 15 | CODE | |
| LOW | testsuite/chdir-symlink-race_test.py | 15 | CODE | |
| LOW | testsuite/delete_test.py | 12 | CODE | |
| LOW | testsuite/delete_test.py | 13 | CODE | |
| LOW | testsuite/alt-dest_test.py | 10 | CODE | |
| LOW | testsuite/alt-dest_test.py | 13 | CODE | |
| LOW | testsuite/alt-dest_test.py | 13 | CODE | |
| LOW | testsuite/temp-dir_test.py | 19 | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | runtests.py | 136 | CODE | |
| LOW | runtests.py | 205 | CODE | |
| LOW | runtests.py | 302 | CODE | |
| LOW | runtests.py | 378 | CODE | |
| LOW | packaging/pkglib.py | 26 | CODE | |
| LOW | packaging/pkglib.py | 174 | CODE | |
| LOW | packaging/pkglib.py | 209 | CODE | |
| LOW | packaging/release.py | 176 | CODE | |
| LOW | packaging/release.py | 290 | CODE | |
| LOW | testsuite/rsyncfns.py | 448 | CODE | |
| LOW | testsuite/rsyncfns.py | 661 | CODE | |
| LOW | testsuite/abdiff.py | 173 | CODE | |
| LOW | testsuite/abdiff.py | 1803 | CODE | |
| LOW | testsuite/abdiff.py | 2248 | CODE | |
| LOW | testsuite/abdiff.py | 2550 | CODE | |
| LOW | testsuite/abdiff.py | 2712 | CODE | |
| LOW | testsuite/perftest.py | 170 | CODE | |
| LOW | testsuite/perftest.py | 282 | CODE | |
| LOW | testsuite/perftest.py | 336 | CODE | |
| LOW | testsuite/perftest.py | 381 | CODE | |
| LOW | testsuite/perftest.py | 394 | CODE | |
| LOW | testsuite/fleettest.py | 568 | CODE | |
| LOW | testsuite/fleettest.py | 873 | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| HIGH | testsuite/copy-dest-source-symlink_test.py | 0 | \ use chroot = no log file = {scratchdir}/rsyncd.log [upload] path = {mod} use chroot = no read only = no | STRING |
| HIGH | testsuite/sender-flist-symlink-leak_test.py | 0 | \ use chroot = no log file = {scratchdir}/rsyncd.log [upload] path = {mod} use chroot = no read only = no | STRING |
| HIGH | testsuite/alt-dest-symlink-race_test.py | 0 | \ use chroot = no log file = {scratchdir}/rsyncd.log [upload] path = {mod} use chroot = no read only = no | STRING |
| HIGH | testsuite/chdir-symlink-race_test.py | 0 | \ use chroot = no log file = {scratchdir}/rsyncd.log [upload] path = {mod} use chroot = no read only = no | STRING |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| MEDIUM | testsuite/daemon-auth_test.py | 23 | # test harness cannot redirect, so it would hang `make coverage` (or any run | COMMENT |
| MEDIUM | testsuite/abdiff.py | 212 | # "is this file hardlinked at all" (link-dest / -H) -- a robust | COMMENT |
| MEDIUM | testsuite/ownership-depth_test.py | 10 | # Rerun under the fleet harness's non-root pass (testsuite/fleettest.py): the uid | COMMENT |
| MEDIUM | testsuite/daemon_test.py | 9 | # Rerun under the fleet harness's non-root pass (testsuite/fleettest.py): a | COMMENT |
| MEDIUM | testsuite/fleettest.py | 85 | # Set from --repo in main() (default: cwd). The harness builds whatever rsync | COMMENT |
| MEDIUM | .github/workflows/fleettest.yml | 3 | # Bitrot check for testsuite/fleettest.py (the developer fleet CI harness). | COMMENT |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | testsuite/abdiff.py | 2420 | except Exception as ex: | CODE |
| LOW | testsuite/abdiff.py | 2739 | except Exception as ex: # never let one scenario kill the pool | CODE |
| MEDIUM | testsuite/abdiff.py | 2736 | def worker(s): | CODE |
| MEDIUM | testsuite/fleettest.py | 722 | def current_branch() -> str: | CODE |
| LOW⚡ | testsuite/fleettest.py | 727 | except Exception: | CODE |
| LOW | testsuite/fleettest.py | 1019 | except Exception as e: # never let one target kill the run | STRING |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| MEDIUM | testsuite/alt-dest_test.py | 33 | # Create a side dir with one identically-named candidate so copy_file()'s | COMMENT |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | testsuite/rsyncfns.py | 1192 | def resolve_beneath_supported() -> bool: | CODE |
| LOW | testsuite/bare-do-open-symlink-race_test.py | 57 | def verify_outside_unchanged_or_absent(label: str, target: str) -> None: | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | packaging/pkglib.py | 20 | # Set this to an encoding name or set it to None to avoid the default encoding idiom. | COMMENT |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | testsuite/abdiff.py | 548 | CODE |