Question

如何避免在BASH中打印错误？我想做这样的事情。如果用户输入了错误的参数（例如“。”），它将退出程序，而不是在终端上显示错误。（我没有在这里发布整个代码......这有点长）。 enter image description here

if [ -n "$1" ]; then
        sleep_time=$1
        # it doesn't work, and displays the error on the screen
        sleep $sleep_time > /dev/null
        if [ "$?" -eq 0 ]; then
                measurement $sleep_time
        else
                exit
        fi

# if invalid arguments passed, take the refreshing interval from the user
else
        echo "Proper Usage: $0 refresh_interval(in seconds)"
        read -p "Please Provide the  Update Time: " sleep_time
        sleep $sleep_time > /dev/null
        if [ "$?" -eq 0 ]; then
                measurement  $sleep_time
        else
                exit
        fi
fi

Answer 1

2>/dev/null会丢弃所有错误。您的代码可以简化为：

#!/usr/bin/env bash

if [[ $# -eq 0 ]]; then
    echo "Usage: $0 refresh_interval (in seconds)"
    read -p "Please provide time: " sleep_time
else
    sleep_time=$1
fi

sleep "$sleep_time" 2>/dev/null || { echo "Wrong time" >&2; exit 1; }

# everything OK - do stuff here
# ...

如何避免在BASH中打印错误？

1 个答案: