Question

您好我是shell script的新用户，我需要处理来自error内部的命令的echo，如下所示

echo -e "some internal command that I can't share \nq" | nc  localhost 10000

我想说

if [[ there's no error ]]

Answer 1

shell变量$?将为您提供退出代码。所以，你可以这样做：

echo -e "some internal command that I can't share \nq" | nc  localhost 10000
rc=$?

if [[ $rc == 0 ]]; then
    echo "success"
fi

或者简单地说，

if echo -e "some internal command that I can't share \nq" | nc  localhost 10000; then
    echo "success"
fi

Answer 2

尝试

echo "YOUR SUPERSECRET COMMAND" | nc localhost 10000 | grep "Your expected error"
if [[ $? -eq 0 ]]; then
   echo "Do something useful with error"
else
   echo "Success"
fi

grep在匹配时返回0，并在找不到匹配的字符串时返回1.

Answer 3

这是一种简洁的方法：

internalcommand &>/dev/null 2>&1 && echo OK || echo FAILED

如果internalcommand成功，OK将打印到stdout，如果失败则打印失败。

在Bash v4上测试的注释

shell脚本处理来自echo

3 个答案: