function fstat
fstat(fd: number,callback: (err: ErrnoException | null,stats: Stats,) => void,): voidfstat(fd: number,options: (StatOptions & { bigint?: false | undefined; }) | undefined,callback: (err: ErrnoException | null,stats: Stats,) => void,): voidoptions: (StatOptions & { bigint?: false | undefined; }) | undefinedcallback: (err: ErrnoException | null,stats: Stats,) => voidvoidfstat(fd: number,options: StatOptions & { bigint: true; },callback: (err: ErrnoException | null,stats: BigIntStats,) => void,): voidoptions: StatOptions & { bigint: true; }callback: (err: ErrnoException | null,stats: BigIntStats,) => voidvoidfstat(fd: number,options: StatOptions | undefined,callback: (err: ErrnoException | null,stats: Stats | BigIntStats,) => void,): voidoptions: StatOptions | undefinedcallback: (err: ErrnoException | null,stats: Stats | BigIntStats,) => voidvoid