{
  "schema_version": 1,
  "generated_at": "2026-11-14T15:35:14.741228+00:00",
  "scope": "Local interprocess exclusive-lock compatibility; not a crash, network or performance test.",
  "environment": {
    "system": "Linux",
    "kernel": "6.8.0-149-generic",
    "architecture": "x86_64",
    "libc": [
      "glibc",
      "2.39"
    ],
    "python": "3.12.3",
    "compiler": "cc (Ubuntu 13.3.0-6ubuntu2~24.04.1) 13.3.0",
    "filesystem": "ext4"
  },
  "protocol": {
    "record_range": {
      "start_byte": 0,
      "length_bytes": 1
    },
    "flock_range": "whole file",
    "mode": "exclusive/write, nonblocking",
    "ownership": "parent holder; child closes inherited fd and opens a new description",
    "release_control": "new child after explicit parent unlock; same file identity verified",
    "repeats_per_optimization": 3,
    "compiler_options": [
      "-std=c11",
      "-Wall",
      "-Wextra",
      "-Werror"
    ]
  },
  "sources_sha256": {
    "probe.c": "ae0c9b5f719e600f220384347ec9bf7dd65a016becd14680720379b2c57bbfb3",
    "run.py": "7602d39952f62a8eb173b96826f32f824835b1aca76f46d4e1c463c583c75d3c",
    "test_matrix.py": "e90787faa8f9914a5fad8e397453a07f0557642474d9e188b7f1944acfe50503"
  },
  "rows": [
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "flock",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "flock",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "flock",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "posix",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "posix",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "posix",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "ofd",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "ofd",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 0,
      "holder": "ofd",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "flock",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "flock",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "flock",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "posix",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "posix",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "posix",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "ofd",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "ofd",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 1,
      "holder": "ofd",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "flock",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "flock",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "flock",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "posix",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "posix",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "posix",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "ofd",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "ofd",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O0",
      "repeat": 2,
      "holder": "ofd",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "flock",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "flock",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "flock",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "posix",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "posix",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "posix",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "ofd",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "ofd",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 0,
      "holder": "ofd",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "flock",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "flock",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "flock",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "posix",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "posix",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "posix",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "ofd",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "ofd",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 1,
      "holder": "ofd",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "flock",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "flock",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "flock",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "posix",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "posix",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "posix",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "ofd",
      "contender": "flock",
      "probes": [
        {
          "phase": "held",
          "acquired": true,
          "errno": 0,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "ofd",
      "contender": "posix",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    },
    {
      "optimization": "-O2",
      "repeat": 2,
      "holder": "ofd",
      "contender": "ofd",
      "probes": [
        {
          "phase": "held",
          "acquired": false,
          "errno": 11,
          "same_file": true
        },
        {
          "phase": "released",
          "acquired": true,
          "errno": 0,
          "same_file": true
        }
      ]
    }
  ]
}