Thursday, January 20, 2011

Use dirs, pushd and popd to manipulate directory stack

You can use directory stack to push directories into it and later pop directory 

from the stack. Following three commands are used in this example. 

o    dirs: Display the directory stack 

o    pushd: Push directory into the stack 

o    popd: Pop directory from the stack and cd to it 

Dirs will always print the current directory followed by the content of the 

stack. Even when the directory stack is empty, dirs command will still print 

only the current directory as shown below. 

# popd 

-bash: popd: directory stack empty 

 

# dirs 

 

# pwd 

/home/ramesh 


How to use pushd and popd? Let us first create some temporary directories 

and push them to the directory stack as shown below. 

 

 

# mkdir /tmp/dir1 

# mkdir /tmp/dir2 

# mkdir /tmp/dir3 

# mkdir /tmp/dir4 

 

# cd /tmp/dir1 

# pushd . 

 

# cd /tmp/dir2 

# pushd . 

 

# cd /tmp/dir3 

# pushd . 

 

# cd /tmp/dir4 

# pushd . 

# dirs 

/tmp/dir4 /tmp/dir4 /tmp/dir3 /tmp/dir2 /tmp/dir1 

 

[Note: The first directory (/tmp/dir4) of the dir 

command output is always the current directory and not 

the content from the stack.] 

 

# dirs 

/tmp/dir4 /tmp/dir4 /tmp/dir3 /tmp/dir2 /tmp/dir1 

 

[Note: The first directory (/tmp/dir4) of the dir 

command output is always the current directory and not 

the content from the stack.] 

 

At this stage, the directory stack contains the following directories: 

 

/tmp/dir4 

/tmp/dir3 

/tmp/dir2 

/tmp/dir1 

 

The last directory that was pushed to the stack will be at the top. When you 

perform popd, it will cd to the top directory entry in the stack and remove it 

from the stack. As shown above, the last directory that was pushed into the 

stack is /tmp/dir4. So, when we do a popd, it will cd to the /tmp/dir4 and 

remove it from the directory stack as shown below. 

 

# popd 

# pwd 

/tmp/dir4 

 

[Note: After the above popd, directory Stack Contains: 

/tmp/dir3 

/tmp/dir2 

/tmp/dir1] 

 

# popd 

# pwd 

/tmp/dir3 

 

[Note: After the above popd, directory Stack Contains: 

/tmp/dir2 

/tmp/dir1] 

 

# popd 

# pwd 

/tmp/dir2 

 

[Note: After the above popd, directory Stack Contains: 

/tmp/dir1] 

 

# popd 

# pwd 

/tmp/dir1 

 

[Note: After the above popd, directory Stack is empty!] 

 

# popd 

-bash: popd: directory stack empty 


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