text: #!/usr/bin/node
  
  const zlib = require('zlib'),
        fs   = require('fs'),
        src  = process.argv[2];
  
  if(process.argv.length !== 3) {
    console.error('命令行参数错误！');
    process.exit(1);
  }
  
  if(!fs.existsSync(src)) {
    console.error('%s not exist!', src);
    process.exit(2);
  }
  
  const dst = src.slice(0, src.length - 3);
  
  fs.createReadStream(src).pipe(zlib.createGunzip()).pipe(fs.createWriteStream(dst));
  