Method toMmapCacheKey

core/src/main/java/io/questdb/std/FdCache.java:241–247

Retrieves memory map cache key for given file descriptor.

(long fd)

     * Retrieves memory map cache key for given file descriptor.
     */
    public synchronized long toMmapCacheKey(long fd) {
        var cacheRecord = openFdMapByFd.get(fd);
        if (cacheRecord == null) {
            return 0;
        }
        return cacheRecord.mmapCacheKey;
    }

    /**
     * Extracts underlying OS file descriptor from cached file descriptor.