1. 区别 builtin command, external command,bash script. 用builtin command(hash.type.command),而不是which命令(external command)查看某个命令是安装了(跟PATH变量相关): hash foo >/dev/null 2>& 1 || echo "I need the command but it not exist" 或者 command -v foo >
一.Managing Services in FreeBSD Service restart will only work if it is set to YES in /etc/rc.conf. To start, stop or restart a service regardless of the settings in /etc/rc.conf, these commands should be prefixed with "one" service sshd oneresta
GNU Parallel Tutorial Prerequisites Input sources A single input source Multiple input sources Linking arguments from input sources Changing the argument separator. Changing the argument delimiter End-of-file value for input source Skipping empty lin
如何修复 Ubuntu 中的“Unable to lock the administration directory (/var/lib/dpkg/)” 在 Ubuntu 或者它的衍生版如 Linux Mint(我已经作为日常工作使用的系统)中使用 apt-get 命令或者其相对更新的APT 管理工具时,你可能会在命令行中看到一个 unable to lock the administration directory (/var/lib/dpkg/) is another process usi
原文地址:http://doc.akka.io/docs/akka/2.0.2/intro/getting-started-first-java.html Introduction Welcome to the first tutorial on how to get started with Akka and Java. We assume that you already know what Akka and Java are and will now focus on the steps