根据社区小伙伴需求，需要合约内查看某账户是否部署了合约，
我们根据setabi action,看下系统合约代码
https://github.com/EOSIO/eosio.contracts/blob/636406b45a4e1d4c3d7b308f6064dfe61b962814/contracts/eosio.system/src/eosio.system.cpp#L361

  void native::setabi( const name& acnt, const std::vector<char>& abi ) {
      eosio::multi_index< "abihash"_n, abi_hash >  table(get_self(), get_self().value);
      auto itr = table.find( acnt.value );
      if( itr == table.end() ) {
         table.emplace( acnt, [&]( auto& row ) {
            row.owner = acnt;
            row.hash = eosio::sha256(const_cast<char*>(abi.data()), abi.size());
         });
      } else {
         table.modify( itr, same_payer, [&]( auto& row ) {
            row.hash = eosio::sha256(const_cast<char*>(abi.data()), abi.size());
         });
      }
   }

当账户部署合约时，会将合约的hash更新到abihash表，所以我们根据这个表，来判断是否部署了合约就好了

cleos -u https://api.eoslaomao.com get table eosio eosio abihash -L eosio.token -l 1

返回数据

{
  "rows": [{
      "owner": "eosio.token",
      "hash": "85fd4e647e88e595223e69d09a3368a14a45d29320ed1515f54fdfac6ca999df"
    }
  ],
  "more": true
}

当合约账户删除部署合约时，

cleos -u https://api.eoslaomao.com set abi -c

这个hash值为

0000000000000000000000000000000000000000000000000000000000000000

结论

判断下对应账户在该abihash表有记录，且hash值不为0000000000000000000000000000000000000000000000000000000000000000，即为已部署合约。

备注

cleos get code 拿到的是 wasm 和 abi 原数据，然后本地计算的hash（查看源代码）,这个一般主要是判断 合约 有没有更新变化用。如果只是判断是否部署合约，还是本文更直接

最近装了ubuntu18.04 LTS，下载软件有点慢，网上搜了下解决方案，大致是两种：一、把/etc/apt/sources.list文件里的源更换一下，改成阿里云或者其它的镜像的文件；二、更换software&updates里的select best server。

一、更换/etc/apt/sources.list文件里的源

1. 备份源列表

Ubuntu配置的默认源并不是国内的服务器，下载更新软件都比较慢。首先备份源列表文件sources.list：

# 首先备份源列表
sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup

2. 打开sources.list文件修改

选择合适的源，替换原文件的内容，保存编辑好的文件, 以阿里云更新服务器为例（可以分别测试阿里云、清华、中科大、163源的速度，选择最快的）：

# 打开sources.list文件
sudo gedit /etc/apt/sources.list

编辑/etc/apt/sources.list文件, 在文件最前面添加阿里云镜像源：

#  阿里源
deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse

3. 刷新列表

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install build-essential

下载速度瞬间就起飞了。

4. 其他源

中科大源：

#  中科大源
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse

163源：

# 163源
deb http://mirrors.163.com/ubuntu/ bionic main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ bionic-security main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ bionic-updates main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ bionic-backports main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ bionic main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ bionic-security main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ bionic-updates main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ bionic-backports main restricted universe multiverse

清华源：

# 清华源
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse

转载自：https://zhuanlan.zhihu.com/p/61228593

windows10 Linux子系统（Ubuntu 18.04）编译EOS报错如下

surou@DESKTOP-444S803:/mnt/c/github/eos$ ./scripts/eosio_build.sh
EOSIO Version: 1.8.6
Sat Jan  4 05:50:58 UTC 2020
User: surou
Current branch: develop
./scripts/eosio_build.sh: line 129: set: -i: invalid option
set: usage: set [-abefhkmnptuvxBCHP] [-o option-name] [--] [arg ...]

原因是子系统的系统名不是Ubuntu

( [[ ! $NAME == "Ubuntu" ]] && [[ ! $ARCH == "Darwin" ]] ) && set -i # Ubuntu doesn't support interactive mode since it uses dash + Some folks are having this issue on Darwin; colors aren't supported yet anyway

查看子系统的Name

surou@DESKTOP-444S803:/mnt/c/github/eos$ echo $NAME
DESKTOP-444S803

所以编译时设置下环境变量即可
编辑环境变量配置文件

vim ~/.bashrc

将下面参数添加到文件尾部

export NAME=Ubuntu
export VERSION_ID=18.04

备注：如果安装1.8.x的EOS，且没配置过环境变量的话，可以一起加上

export PATH=$PATH:/home/surou（当前用户名）/eosio/1.8/bin

然后刷新环境变量

source ~/.bashrc

然后再次执行

surou@DESKTOP-444S803:/mnt/c/github/eos$ ./scripts/eosio_build.sh