#pushd

리눅스/유닉스(물론 맥도)의 명령어 중에 은근히 유용하지만 의외로 많이 모르는 명령어들이 좀 있다. 그 중 최근에 팀원에게 가르쳐 준 명령어가 있는데 바로 pushd/popd라는 명령어다.

아주 간단한 명령어로, pushd로 다른 디렉토리로 이동했다가 popd로 다시 현재 디렉토리로 돌아오는 콤비 명령어다.

예를들어, 내가 현재 작업하고 있는 디렉토리가 /usr/local/lib/node_modules/lodash 인데, nginx 설정을 좀 바꾸러 /etc/ngnix/conf.d 로 갔다가 오려면, 일반적으로는 다음 조합의 명령어를 써야할 것이다.

pwd (경로 확인 및 복사)

cd /etc/ngnix/conf

cd conf.d

cd ...

cd /usr/local/lib/node_modules/lodash

하지만 pushd/popd 를 이용하면

cd /etc/ngnix/conf

cd conf.d

cd ...

popd

끝! 엄청 편하지 않은가? ㅎㅎ 참고로 pushd를 연속으로 사용하고 popd로 순서대로 돌아올 수도 있다.

물론 로컬 컴퓨터에서 작업한다면 터미널을 새로 띄워서 작업하거나, screen 등으로 작업하는 방법도 있지만, 그래도 기억해두면 서버작업을 하거나 할 때 꽤 유용하게 쓰일 일이 많은 명령어이니 기억해두면 좋을 것이다.

I am going to give you my interpretation of pushd and popd... Okay so you have  folder called Motivation. In Motivation you have two directories established, one is called great and another is called special.  In each file you have some motivational text. 

So I want a way to go to each file quickly and efficiently because I want to get motivated now.  What you can do is put it in a holding section that will allow your motivation to come to you sooner.  

The minute you type pushd the folder will switch back and forth between 'great' and 'special' because that was in your holding space. 

So, I had to pop off a '~/special' because they were two in the holding area and I didn't need two to be in there. That means it will just go back and forth to the same folder therefore same motivation. If I pop it off by using popd I can have great and special the only two things in the holding area and switch back and forth amongst those two. 

So how do you get things into the current holding? You type 'pushd .' that means 'push directory current' into holding. I made sure I did this in the directory that I wanted to push into the holding area. 

We will implement a stack as an environment variable containing a list of dirs separated by space.

Your dir stack should be initialized to the null string when you log in. To do this, put this in your .bash_profile:

DIR_STACK=""

export DIR_STACK

Do not put this in your environment file.

Next we need to implement pushd and popd as functions. Here are our initial versions:

pushd ()

{

dirname=$1

DIR_STACK="$dirname $DIR_STACK:-$PWD ' ' }"

cd ${dirname:?you may type wrong name Boss."}

echo "$PWD"

}

popd ()

{

DIR_STACK= ${DIR_STACK#*}

cd ${DIR_STACK%% *}

echo "PWD"

}