Procs

proc fcntl(fd: int; cmd: string; arg = 0): string {.
    ...raises: [Exception, ValueError, OSError, IOError, EOFError, KeyError],
    tags: [RootEffect].}

proc ioctl(fd, request: int; arg = 0; mutate_flag = true): string {.
    ...raises: [Exception, ValueError, OSError, IOError, EOFError, KeyError],
    tags: [RootEffect].}

proc lockf(fd: int; cmd: string; len = 0; start = 0; whence = 0): string {.
    ...raises: [Exception, ValueError, OSError, IOError, EOFError, KeyError],
    tags: [RootEffect].}